Network +

Question 2

what are networks used for ?

Answer 2

networks are used to make connections between machines

Question 2

server

Answer 2

a device that provides resources to the rest of the network

Question 3

what is a client ?

Answer 3

a device used by an end-user to access the network

Question 4

what is a wireless access point

Answer 4

a device that allows wireless devices to connect into a wired network

Question 5

what is a switch?

Answer 5

a device that connects network devices together

operates at layer 2 of the OSI model

switches learn MAC address’s by analyzing incoming traffic, when it sees a mac address not in its table it adds it

Question 6

what can switches learn ?

Answer 6

switches can learn what devices are on what ports

Question 7

What is the primary function of a Router?

Answer 7

used to connect two different networks together and forwards traffic to and from the network

Question 8

what is Media in a network?

Answer 8

connects two devices or a device to a switch port

Question 9

what is the point of a Wide Area Network or WAN?

Answer 9

physically connects two geographical dispersed networks

Question 10

how does the client server model work?

Answer 10

uses a dedicated server to provide access to files, scanners, printers and other resources

Question 11

benefits of the client to server model ?

Answer 11

• administration and backup are easier under this model
• centralized administration
• easier management
• better scalability

Question 12

disadvantages of the client server model

Answer 12

-higher cost
- requires specialized OS
-requires dedicated resources

Question 13

what is the peer to peer model?

Answer 13

peers share resources files/printers directly with others

Question 14

benefits of the peer to peer model

Answer 14

• lowcost
• no dedicated resource
• No specialized OS

Question 15

drawbacks of the peer to peer model

Answer 15

decenetralized managament
inefficient for large networks
poor scalability

Question 16

Pan?

Answer 16

personal area network

Question 17

examples of a Pan network ?

Answer 17

bluetooth devices
Usb devices

Question 18

explain a LAN or local area network ?

Answer 18

connects components within a limited distance
up to a few hundred feet
small offices

Question 19

what standard does ethernet use ?

Answer 19

ethernet uses the IEEE 802.3 standard

Question 20

what standard does wifi use ?

Answer 20

wifi uses the 802.11 standard

Question 21

what is a CAN or campus area network ?

Answer 21

connects LANs that are building centric across a university, industrial park or business park

Question 22

what does a MAN metropolitian area network connect?

Answer 22

connects scattered locations across a city or metro area ?

Question 23

WAN wide area network

Answer 23

connects geographically disparate internal networks and consists of leased lines or VPNs
covers a large geographic area
the internet is the largest WAN avaliable

Question 24

Wan distance?

Answer 24

world wide

Question 25

MAN distance

Answer 25

city or county

Question 26

CAN distance

Answer 26

campus area or business park

Question 27

LAN distance

Answer 27

room or building

Question 28

PAN distance

Answer 28

around a person

Question 29

what does phsical mean in a network

Answer 29

how devices are connected by media

Question 30

what does logical mean in a network

Answer 30

how the actual network traffic flows

Question 31

Bus topology ?

Answer 31

uses a single cable where each device taps into by using either a vampire tap or a T connector

Question 32

Ring topology ?

Answer 32

uses a cable running in a circular loop where each device connects to the ring but data travels in a singular direction

Question 33

Ring topology: Token ring ?

Answer 33

ring topology that uses an electronic token to prevent collosions when communicating on the network

Question 34

Ring topology: what does FDDI use ? explain FDDI

Answer 34

uses two counter rotating rings for redundancy

Question 35

star topology ?

Answer 35

• most popular phsical LAN topology
• the central point of a star network is most likely going to be a switch

Question 36

what is a drawback to a star topology ?

Answer 36

if the central device fails the whole network fails

Question 37

Wireless: infastructure mode ?

Answer 37

uses a wireless access point as a centralized point and supports wireless security controls

Question 38

Wireless: Ad Hoc mode ?

Answer 38

decentralized wireless network which creates P2P connections and does not require a router or access

Question 39

Wireless mesh topology ?

Answer 39

interconnection of different types of nodes, devices, or radios

Question 40

what does OSI stand for ?

Answer 40

OSI stands for open systems interconnection model

Question 41

what are the 7 layers of the OSI model starting from Layer 1?

Answer 41

1. phsical
2. Data Link
3. Network
4. Transport
5. Session
6. Presentation
7. Application

Question 42

what is the phsical layer?

Answer 42

• where transmission of bits across the network occurs includes phsical and electrical network characteristics

Question 43

what does the phsical layer decide ?

Answer 43

the phsical layer decides the topology of the network

Question 44

what is asynchronous communication?

Answer 44

uses start and stop bites to indicate when transmissions occur from the sender to the reciever

Question 45

what is a good example of asynchronous communication ?

Answer 45

something like a voicemail is a good example

Question 46

what is synchronous communication ?

Answer 46

uses a refrence clock to coordinate the transmissions by both the sender and the reciever

Question 47

broadband communication ?

Answer 47

divides our bandwidth into seperate channels

Question 48

what is baseband communication ?

Answer 48

uses all availiable frequencies on a medium (cable to transmit data)

Question 49

what is time division multiplexing ?

Answer 49

each session takes a turn using time slots to share the medium between users

Question 50

what is multiplexing ?

Answer 50

multiplexing is getting more out of a limited network

Question 51

what are some examples of Physical layer devices ?

Answer 51

• cable
• ethernet
• coaxial
• hubs
• access points
• media converters

Question 52

what do layer 1 devices primarily do ?

Answer 52

usually they repeat what they are told.

Question 53

what is the primary function of the data link layer?

Answer 53

packages data into frames and transmit those frames on the network

Question 54

what do the first and second parts of a MAC address represent ?

Answer 54

the first 6 digits in a MAC address are the vendor code the second 6 are the unique value

Question 55

Logical link control LLC ?

Answer 55

provides connection services and allows acknowledgment of receipt of messages

Question 56

what are some examples of devices at the data link layer?

Answer 56

NIC’s
Bridges
Switches

Question 57

what is the primary function of layer 3 the network layer?

Answer 57

forwards routing traffic with logical addressing

• the routing layer
• fragments frames to travers different networks

Question 58

what are two common layer 3 protocols ?

Answer 58

IPV4 and IPV6

Question 59

what is the big question at layer 3?

Answer 59

the big question at layer 3 is how data should be forwarded or routed.

Question 60

how does Packet switching / routing work ?

Answer 60

data is divided into packets and then forwarded based on IP address

Question 61

what is circuit switching ?

Answer 61

dedicated communication link is established between two devices for the duration of the communication

Like a phone call

Question 62

what is message switching ?

Answer 62

data is divided into messages which may be stored then forwarded

Question 63

what do routers maintain ?

Answer 63

a routing table

Question 64

what is ICMP?

Answer 64

sends error messages and operational info to an IP address
most commonly used ICMP is ping

Question 65

what are common devices found on layer 3?

Answer 65

Routers
multi-layer switches
ip and routers are the most common

Question 66

what do we call the transport layer?

Answer 66

the transport layer is the dividing line between what we call the upper layers of the OSI model and the lower layers of the OSI model

Question 67

when we talk about segments and datagrams what layer are we talking about?

Answer 67

we are talking about the transport layer

Question 68

what are two protocols in the transport layer?

Answer 68

• TCP
  -UDP

Question 69

transmission control protocol ?

Answer 69

connection oriented protocol that is a reliable way to transport segments across the network

Question 70

what is the UDP user datagram protocol ? EXPLAIN

Answer 70

connectionless protocol that is an unreliable way to transport segments across the network

Question 71

what does connectionless mean ?

Answer 71

connectionless means it doesn’t have to wait for connections

Question 72

EXAM: layer 4 what is layer 4 associated with

Answer 72

layer 4 is associated with segments almost exclusively because we use it with TCP

• TCP and UDP operate at layer 4

Question 73

what is UDP very good for ?

Answer 73

udp is very good for audio and visual streaming

Question 74

windowing ?

Answer 74

allows the clients to adjust the amount of data in each segment

Question 75

what are some examples of layer 4 devices?

Answer 75

• TCP & UDP
• WAN accelerators
• Load balancers and firewalls

Question 76

what is the primary function of the session layer ?

Answer 76

keeps conversations separate to prevent intermingling of data

• manages communication between devices start, stop ,restart
• tunneling occurs at this layer

Question 77

how do sessions work in three steps ?

Answer 77

set up
maintain
tear down

Question 78

explain setting up a session

Answer 78

checking of user credentials and assigning numbers to sessions to help identify them

Question 79

explain tearing down a session

Answer 79

ending of a session after the transfer is done or when the other party disconnects

Question 80

what is the primary focus of the presentation layer?

Answer 80

formats the data to be exchanged and secures the data with proper encryption

• Character encoding

Question 81

what should we remember when we think about layer 6?

Answer 81

when you think about layer 6 remember data formatting and encryption

the presentation layer is responsible for formatting and encryption

Question 82

what is data formatting ?

Answer 82

data is formatted by the computer to have compatibility between different devices

Question 83

encryption ?

Answer 83

used to scramble the data in transit to keep it secure from prying eyes and provide data confidentiality

Question 84

what is the primary function of layer 7?

Answer 84

provides application level services where users communicate with the computer

Question 85

what are some things found on layer 7?

Answer 85

• email applications
• web browsing
• DNS
• FTP
  -RDP

Question 86

what are the 4 layers of the tcp ip model >

Answer 86

1. network interface
2. internet
3. transport
4. application

Question 87

what makes up the application layer in the tcp/ip model?

Answer 87

the top three layers of the OSI model are all called the application layer in the TCP/IP model

so the session presentation and application layers

Question 88

what is the network interface layers function in the TCP/ip model ?

Answer 88

describes how to transmit bits across the network and determines how the network medium is going to be used

Question 89

what is the function of the internet layer in the TCP/IP model ?

Answer 89

data is taken and packaged into IP datagrams

Question 90

what are some examples of protocols in the internet layer for the TCP/IP model

Answer 90

IP
ICMP
ARP
Reverse ARP

this is essentially the network layer of the OSI model so IP’s - ARP etc

Question 91

what is the transport layers function in the TCP/IP model ?

Answer 91

defines the level of service and the status of the connection being used by TCP, UDP, or RTP

-support for end to end services

• support fo multiplexing
• support for port numbers mapping

Question 92

what is the application layer’s function in the TCP/IP model ?

Answer 92

dictates how programs are going to interface with the transport layer by conduction session management

Question 93

what is a port ?

Answer 93

logical opening on a system representing a service or application thats listening and waiting for the traffic

Question 94

how many ports are there

Answer 94

65,535

Question 95

how many well known or reserved ports are there ?

Answer 95

the well known or reserved port are 0-1023

Question 96

ephermal ports ?

Answer 96

1024-65,535

Question 97

what does an IPv4 packet consist of ?

Answer 97

• source address
  -destination address
• ip flags
• protocol

Question 98

secure shell ssh

Answer 98

port 22
provides secure remote control of another machine using a text based environment

Question 99

secure file transfer protocol SFTP

Answer 99

port 22
provides secure file transfers

Question 100

Telnet

Answer 100

port 23
provides insecure remote control of another machine . remote access via the command prompt

Question 101

simple mail transfer protocol SMTP

Answer 101

port 25
provides the ability to send emails over the network

Question 102

Domain name services DNS

Answer 102

port 53
converts domain names to IP addresses and IP addresses to domain names

Question 103

what port does Dynamic host control protocol or DHCP run on ?

Answer 103

ports 67,68
automatically provide network parameters to your clients such as their assigned ip address, subnet mask, default gateway, and the DNS server they should use

Question 104

what port is trivial file transfer protocol TFTP?

What is TFTP typically used for ?

Answer 104

port 69 UDP
used as a lightweight file transfer method for sending configuration files or network booting of an operating system
usually used for sending or recieving config file from a router or switch

Question 105

Hyper text transfer protocol HTTP

Answer 105

port 80
used for insecure web browsing

Question 106

what port is POP3?

what is POP3 used for ?

Answer 106

port 110
used for recieving incoming emails

Question 107

Network Time protocol NTP

Answer 107

port 123 UDP
used for keeping accurate time within a network

Question 108

Network basic input/output system NetBios

Answer 108

port 139 TCP
used for file or printer sharing in a windows network

Question 109

internet mail application protocol IMAP

Answer 109

port 143 TCP

a newer method of retrieving incoming emails which imporves upon the older POP3

Question 110

simple network management protocol SNMP

Answer 110

ports 161,162 UDP

used to collect data about network devices and monitor there status

Question 111

Lightweight directory access protocol LDAP

Answer 111

ports 389 TCP

used to provide directory services to your network

Question 112

Hypertext transfer protocol secure HTTPS

Answer 112

port 443 used for secure web browsing

Question 113

server message block SMB

Answer 113

port 445 TCP

used for windows file and printer sharing services

Question 114

system logging protocol syslog

Answer 114

port 514 UDP

used to send logging data back to a centralized server

Question 115

simple mail transfer protocol transport layer security SMTP TLS

Answer 115

port 587 TCP

secure and encrypted way to send emails

Question 116

Lighweight directory access protocol secure

Answer 116

port 636 provide directory services in a secure way

Question 117

POP3 over SSL

Answer 117

port 995 secure and encrypted way to recieve emails

Question 118

structured query language server protocol SQL

Answer 118

port 1433 used for communication from a client to the database engine

Question 119

Microsoft structured query language

Answer 119

port 3306 used for communication from a client to Mysql database engine

Question 120

Remote Desktop protocol RDP

Answer 120

port 3389 provides graphical remote control from another client to a server

Question 121

what is TCP what layer of the OSI model is it on?

Answer 121

TCP is a transport layer protocol that operates at layer 4 of the OSI model

Question 122

how does TCP work ?

Answer 122

TCP operates by conducting a three way handshake between a client and a server and then establishes the connection

Question 123

what is TCP considered?

Answer 123

TCP is considered connection oriented

Question 124

what is UDP considered ?

Answer 124

UDP is considered fast and easy to use

Question 125

what is ICMP

Answer 125

ICMP is used to communicate information about network connectivity isssues back to the sender ping is a great example of ICMP

Question 126

Generic routing encapsulation or GRE?

Answer 126

used as a simple and effective way to create a tunnel called a GRE tunnel over a public network

Question 127

do GRE tunnels provide us with any encryption ?

Answer 127

They do not

Question 128

Internet Protocol Security IPsec

Answer 128

used to protect one or more data flowes between peers and it uses encryption

Question 129

what security controls will implemeting IPSec accomplish for us ?

Answer 129

1. data confidentiality
2. data integrity
3. origin authentication
4. Anti-replay

Question 130

what two protocols does IPSec use to achieve encryption ?

Answer 130

AH and ESP

Question 131

IPSec: AH authentication header?

Answer 131

a protocol within IPSec that provides integrity and authentication

Question 132

IPSec: Encapsulating Security Payload or ESP?

Answer 132

provides encryption and integrity for the data packets sent over IPSec

Question 133

what are the three types of media?

Answer 133

1. copper
2. fiber optic
3. wireless

Question 134

what is media ?

Answer 134

matariel used to transmit data over the network

Question 135

what are the three types of copper media ?

Answer 135

1. coaxial
2. twisted pair
3. serial

Question 136

what are f-type connectors ?

Answer 136

F-type connectors are a screw on type of connector

Question 137

what are the two types of twisted pair cabeling ?

Answer 137

UTP or STP

Question 138

what does UTP stand for ?

Answer 138

UTP stands for unshielded twisted pair

Question 139

what does STP stand for

Answer 139

shielded twisted pair

Question 140

what are the two ways someone can get access to a network ?

Answer 140

Deterministic and Contention based

Question 141

deterministic ?

Answer 141

very organized and orderly and requires an electronic token to transmit. Like a student in a classroom getting called on

Question 142

contention based networks ?

Answer 142

very chaotic and can transmit whenever possible.

Question 143

what is the problem with contention based networks ?

Answer 143

you can have collosions

Question 144

does ethernet use a contention or deterministic method ?

Answer 144

contention

Question 145

how does ethernet prevent collosions ?

Answer 145

Ethernet prevents colisions with CSMA/CD

Question 146

Carrier sense multiple access with collision detection CSMA/CD?

Answer 146

prevents collosions by using carrier-sensing to defer transmissions until no other stations are transmitting.

Question 147

what is a collision domain ?

Answer 147

each area of the network that shares a single segment is known as a collision domain

collision domain devices in a group whose frames can collide with each other

Question 148

what does adding an ethernet switch do for our network ?

Answer 148

increases scalability of a network by creating multiple collision domains

Question 149

bandwidth?

Answer 149

measures how many bits the network can transmit per second

Question 150

how far can multi-mode fiber reach?

Answer 150

multimode fiber can reach distances of 200-500 meters

Question 151

how far can single mode fiber travel ?

Answer 151

single mode fiber can go up to 40 kilometers

Question 152

how far can copper cables transmit data ?

Answer 152

maximum distance of a 100 meters

Question 153

Using cat 6 at 100 meters what will the speed be ?

Answer 153

Using CAT 6 at 100 meters will limit the speed from 10 Gbps to 1 Gbps

Question 154

what speed will you get using CAT 6 at under 55 meters.

Answer 154

Using CAT 6 at under 55 meters can reach 10 Gbps of speed

Question 155

what type of fiber should we use for long distances ?

Answer 155

single mode fiber

Question 156

what sort of fiber do we need to use with long distances ?

Answer 156

fiber for long distances you need to use single mode

Question 157

what is a hub?

Answer 157

also known as a multi-layer repeater it is a layer 1 device that connects multiple network devices and workstations.

Question 158

what are the three types of hubs ?

Answer 158

1. Passive hub
2. active hub
3. smart hub

Question 159

Passive hub ?

Answer 159

repeats signal with no amplification

Question 160

Active hub ?

Answer 160

repeats signal with amplification

Question 161

smart hub ?

Answer 161

active hub with enhanced features like SNMP

Question 162

how does a bridge make forwarding decisions?

Answer 162

analyzes source MAC address and makes intelligent forwarding decscions based on the destination MAC in the frames

Question 163

switch ?

Answer 163

also known as a multiport bridge it is a layer 2 device that connects multiple network segments together .

Question 164

what is a switch essentially?

Answer 164

a switch is essentially a multi-port bridge

Question 165

what layer does a router operate at ?

Answer 165

a router is a layer three device

Question 166

what is a router?

Answer 166

layer 3 device that connects multiple networks and makes forwarding decisions based on logical network information

Question 167

what is a layer 3 switch ?

Answer 167

makes layer 3 routing decisions and then interconnects entire networks not just the network segments

Question 168

EXAM: switch ?

Answer 168

layer 2 device focused on MAC addresses

Question 169

Exam: router ?

Answer 169

layer 3 device focused on IP addresses

Question 170

what are some additional features switches can offer ?

Answer 170

1. VLANs
2. Trunking
3. STP
4. Link aggregation
5. power over ethernet
6. Port monitoring
7. User authentication

Question 171

what is link aggregation?

Answer 171

combines multiple phsical connections into a single logical connection to minimize or prevent congestion

Question 172

what is the standard for link aggregation ?

Answer 172

IEEE 802.3ad

Question 173

are switches full duplex ?

Answer 173

switches are full duplex which means every port can operate at 100mbps

Question 174

power over ethernet ?

Answer 174

supplies electrical power over ethernet and requires cat 5 or higher copper cable.

Question 175

what is the benfit of power over ethernet ?

Answer 175

the benefit of power over ethernet is instead of needing two seperate cables for power and data you can use one cord for both

Question 176

port mirrioring ?

Answer 176

makes a copy of all traffic destined for a port and sends it to another port

Question 177

switches can provide additional features such as ?

Answer 177

1. port mirrioring
2. secure shell ssh
3. ot-of-band-management
4. first hop redundancy
5. MAC filtering
6. traffic filtering

Question 178

out-of-band management ?

Answer 178

keeps all network configurations devices on a seperate network

Question 179

First hop redundancy

Answer 179

uses hot standby router protocol to create a virtual IP and MAC addresses to provide active and stanby routers

Question 180

How do devices such as a switch do traffic filtering at layer 2 ?

Answer 180

permits or denies traffic based on a device’s MAC address

Question 181

what is the standard for spanning tree protocol ?

Answer 181

802.1d

Question 182

spanning tree protocol STP ?

Answer 182

permits redundant links between switches and prevents loopong of network traffic

STP is the IEEE 802.1d standard

Question 183

shortest path bridging SPB

Answer 183

used instead of STP for larger network environments

Question 184

VLAN ?

Answer 184

allows different logical networks to share the same phscial hardware and provides added security and efficiency

Question 185

when do routers start to come into play ?

Answer 185

Routers start to come into play once we leave our local area network

Question 186

Definition: Router

Answer 186

forwards traffic between subnets, between an an internal and external network or between two external networks

Question 187

what makes a broadcast domain

Answer 187

each subnet or external network is going to be its own broadcast domain

Question 188

can a multi layer switch function as a router ?

Answer 188

if you are using an external switch it is functioning as a router

Question 189

how do routers make decisions?

Answer 189

routers make there routing decisions by using a routing table

Question 190

Routing table?

Answer 190

helps determine which route entry is the best fit for the network

Question 191

how do routers map an IP address to a MAC address?

Answer 191

routers use an arp cache to map an IP address to a given MAC address

Question 192

what are the three different sources that a router can use ?

Answer 192

1. Directly connected route
2. Static route
3. Dynamic route

Question 193

Routing: Directly connected route ?

Answer 193

learned by physical connections between routers

Question 194

Routing: static route ?

Answer 194

• manually configured by an admin
• there is always one default standard route in every router that is 0.0.0.0/0

Question 195

Routing: Dynamic routing ?

Answer 195

learned by exchanging information between routers

routers send routes to other routes

Question 196

what are the two ways we can prevent routing loops ?

Answer 196

1. split horizon
2. Poising reverse

Question 197

Split Horizon ?

Answer 197

prevents a route learned on one interface from being advertised back out on the same interface.

Question 198

Poising reverse ?

Answer 198

causes a route received on one interface to be advertised back out on the same interface with a metric considered to be infinite

Question 199

what are the two different types of dynamic routing protocols ?

Answer 199

1. internal
2. external

Question 200

Internal dynamic routing protocols?

Answer 200

1. interior gateway protocol IGP
   - operates within an autonomous system
   - Example: Intranet

We use this routing protocol to route within our internal networks

Question 201

External dynamic routing protocols ?

Answer 201

1. Exterior gateway protocol EGP
   - operate between autonomous systems
   - example Internet

BGP is one of the most commonly used routing protocols for EGP

Question 202

Routing: Distance vector ?

Answer 202

Distance vector routing algorithm simplifies the routing process by assuming the cost of every link is one unit. Therefore, the efficiency of transmission can be measured by the number of links to reach the destination. In Distance vector routing, the cost is based on hop count

Question 203

Routing: convergence ?

Answer 203

time it takes for routers to update their routing table in response to a topology change

Question 204

Routing: hold down timer ?

Answer 204

prevents updates for a specific period of time and speeds up convergence

Question 205

Routing: hop count ?

Answer 205

number of routers from the source router through which data must pass to reach the destination network

Question 206

Routing: Link state routing protocol ?

Answer 206

requires all the routers to know about the paths that all other routers can reach in the network

every node constructs a map of the connectivity to the network, in the form of a graph, showing which nodes are connected to which other nodes.

Examples of link state routing protocols include OSPF and ISIS

Question 207

Routing: what is RIP or the routing information protocol?

Answer 207

Interior routing protocol

a distance vector protocol that uses hop count - maximum number of hops it can do is 16

Question 208

RIP features

Answer 208

1. updates every 30 seconds
2. easy to configure
3. Runs over UDP

Question 209

open shortest path first OSPF?

Answer 209

1. a link state protocol that uses cost
2. interior gateway protocol

Question 210

Routing: OSPF?

Answer 210

OSPF is known as a classless protocol, classless routing protocols are those protocols that include subnet mask information when the routing table or updates are exchanged

Question 211

Routing: intermediate system to intermediate system or IS-IS?

interior or exterior protocol ?

Answer 211

a link state protocol that also uses cost and functions like the OSPF protocol but is not widely popular
- interior routing protocol

Question 212

Routing: Enhanced interior gateway routing protocol EIGRP?

Answer 212

hybrid of distance vector and link state protocols that uses bandwidth and delay
- interior routing protocol

cisco protocol

Question 213

Routing: what is BGP or border gateway protocol?

Is BGP an interior or exterior routing protocol ?

Answer 213

a path vector that uses the number of autonmous system hops instead of router hops/ bgp is an external routing protocol - this is more concerned with how many systems you have to go through

Question 214

Routing: route belivability ?

Answer 214

if a route has a lower administrative distance the route is more believable

Question 215

network address translation NAT?

Answer 215

translates private IP addresses to public IP addresses for routing over public networks

Question 216

What are the three different types of address translation ?

Answer 216

1. DNAT Dynamic NAT
2. SNAT static NAT
3. PAT port address translation

Question 217

NAT: DNAT dynamic nat

Answer 217

automatically assigns an IP address from a pool and gives a one to one translation

Question 218

NAT: SNAT static nat

Answer 218

manually assign an IP address and gives one to one translation

static Nat was primarily used as a security feature

Question 219

NAT: PAT port address translation

Answer 219

most common one used today

sharing on one public IP by multiple private IP addresses which gives a many to one translation

Question 220

inside local ?

Answer 220

private ip address refrencing an inside device

Question 221

inside global ?

Answer 221

public IP address refrencing from an inside device

Question 222

outside global?

Answer 222

public IP address referencing an outside device

Question 223

Outside local ?

Answer 223

private IP address refrencing an outside device

Question 224

Outside local

Answer 224

private ip address refrencing an outside device

Question 225

multicast routing ?

Answer 225

multicast sender sends traffic to a class D IP address known as a multicast group

main goal of multicast routing is to send the traffic only to devices that wish to recieve the traffic

the two primary protocols used for multicast routing are IGMP and PIM

Question 226

what are the two primary ways of doing multicast routing ?

Answer 226

IGMP internet group management protocol
PIM protocol independent multicast

Question 227

IGMP internet group management protocol

Answer 227

lets routers know which interfaces have multicast recievers and allow clients to join a multicast group

Question 228

PIM protocol independent multicast ?

Answer 228

routes multicast traffic between multicast enabled routers

Question 229

Virtualization

Answer 229

allows multiple virtual instances to exist on a single physical server

Question 230

Hypervisor

Answer 230

enables virtualization to occur and emulates the physical hardware

Question 231

Popular hypervisors

Answer 231

VMWare ESXi

Microsoft Hyper-V

Virtual box

Vmware Workstation

Question 232

what is a bare metal hypervisor ?

Answer 232

bare metal hypervisor is when you just run the hypervisor as the OS

Question 233

Network attached storage NAS?

Answer 233

disk storage delivered as a service over TCP/IP

Question 234

Storage area network SAN?

Answer 234

specialized LAN that transfers data at block level with a special protocol

To the users it looks and acts like a local drive

A storage area network or storage network is a computer network which provides access to consolidated, block-level data storage. SANs are primarily used to access data storage devices, such as disk arrays and tape libraries from servers so that the devices appear to the operating system as direct-attached storage

Question 235

Fiber channel FC?

Answer 235

special purpose hardware providing 1-16 GBPS of storage area network speed

Question 236

what is Fiber channel over ethernet or FCOE

what purpose does it serve in our networks?

Answer 236

removes the need for specialized hardware and runs FC over ethernet frames

Question 237

IP small computer systems interface ISCSI

Answer 237

lowers cost and relies on configuration that allows jumbo frames over the network

Question 238

InfiniBand ?

Answer 238

virtualized storage technology that uses a switched fabric topology and features very high throughput and very low latency

Question 239

what problem does a virtual switch solve?

Answer 239

overcomes the problem of all virtual servers being on one broadcast domain

Question 240

Virtual desktop?

Answer 240

a desktop computer that is run on a browser using the web

Question 241

software defined networking SDN?

Answer 241

provides an easy to use front end to configure physical and virtual devices through a network

Question 242

what is the purpose of VOIP?

What does VOIP do for our networks?

Answer 242

digitizes voice traffic to be treated like other traffic on the network

Question 243

what protocol does VOIP use ?

Answer 243

VOIP uses a protocol known as SIP

Sip is used to setup and manage voip sessions

SIP can also extend voice communication to include video conferencing, instant messaging, file transfers and more

Question 244

Session initiation protocol SIP?

Answer 244

used to setup, maintain, and tear down calls

Question 245

private cloud ?

Answer 245

systems and users only have access with other devices inside the same private cloud or system

Question 246

public cloud ?

Answer 246

systems and users interact with devices on public networks such as the internet and other clouds

Question 247

Hybrid cloud ?

Answer 247

combination of public and private clouds

Question 248

community cloud ?

Answer 248

collaborative effort where infrastructure is shared between several orgs from a specific community with the same concerns

Question 249

Network as a service Naas

Answer 249

allows for the outsourcing of a network service provider

Question 250

Infrastructure as a service IaaS

Answer 250

allows for the outsourcing of infrastructure of the servers and desktops to a service provider

Question 251

Software as a service SaaS

Answer 251

users interact with a web based application and the details of how it works are hidden – examples of Saas products include m065 and google docs

Question 252

Platform as a service Paas

Answer 252

provides a platform for companies that develop applications without the need for infrastructure – digital ocean

Question 253

Desktop as a service Daas

Answer 253

provides a desktop environment that is accessible through the internet in the form of a cloud desktop or virtual desktop environment

Question 254

Cloud: elasticity?

Answer 254

attempts to match the resources allocated with the actual amount of resource needed at any given point and time

Question 255

Cloud: what is elasticity focused on ?

Answer 255

elasticity is focused on meeting the sudden increase and decreases in a workload

Question 256

Cloud: scalability ?

Answer 256

handles the growing workload required to maintain good performance and efficiency for a given software or application

Question 257

Is scalability a long term approach ?

Answer 257

Scalability is common to be used long term elastic approaches can change every day or every minute

Question 258

Cloud: vertical scaling ?

Answer 258

increases the power of the existing resources in the working environment

Question 259

cloud: horizontal scaling ?

Answer 259

adding additional resources to help handle the extra load being experienced

adding additional instances instead of moving to a larger instance size

Question 260

cloud: multitenancy

Answer 260

allowing customers to share computing resources in a public or private cloud

Question 261

what are the benefits of multitenancy solutions ?

Answer 261

1. better storage
2. better use of resources
3. lower overall cost

Question 262

Virtual machine VM escape ?

Answer 262

occurs when an attacker break out of one of the isolated VMs and begins to directly interact with the underlying hypervisor

Question 263

infrastructure as code IAC ?

Answer 263

enables managing and provisioning of infrastructure through code instead of through manual processes

Question 264

how do we use IAC effectively ?

Answer 264

To use IAC effectively we need to use scripted automation and orchestration

Question 265

Cloud: orchestration ?

Answer 265

process of arranging or coordinating the installation and configuration of multiple systems

Question 266

Snowflake system?

Answer 266

any system that is different from the standard configuration template

Question 267

Cloud: private direct connection ?

Answer 267

extends pre-existing on premise data center into the providers network to directly connect to your virtual private cloud network

establishes a secure, dedicated connection from your infrastructure into AWS.

Question 268

Cloud: datacenter ?

Answer 268

any facility that businesses and other orgs use to organize, process, store, and disseminate large amounts of data

Question 269

Cloud: what are the three main layers in a three tiered hierarchy ?

Answer 269

1. core
2. Distribution aggregation
3. access edge

Question 270

Three tiered hierarchy: explain the Core

what is the core’s function in the three tiered hierarchy

Answer 270

• big fast expensive routers
• backbone of the cloud network

Question 271

Three tiered hierarchy: distribution aggregation

what is the function of the distribution aggregation layer in the cloud three tired hierarchy

Answer 271

• provides boundary definitions by implementing ACL’s and policies
• layer three switches
• packets are being properly routed

Question 272

Three tiered hierarchy: access edge

Answer 272

• connect to endpoint devices
• regular switches

Question 273

what are the 4 layers we need to be aware of with SDN?

Answer 273

1. Application layer
2. control layer
3. infrastructure layer
4. management plane

Question 274

SDN layer: application layer ?

Answer 274

focuses on the communication resource requests or info about the network as a whole

Question 275

SDN layer: control layer?

Answer 275

uses the information from the application and decides how to route a packet on the network

Question 276

SDN layer: infrastructure layer?

Answer 276

contains the network devices that receive information about where to provide the data and then perform those movements

Question 277

SDN layer: Management plane?

Answer 277

used to monitor traffic conditions and the status of the network.

Question 278

what can we achieve with a spine and leaf architecture

Answer 278

By using a spine and leaf architecture we can give faster speeds and lower latency than the traditional three-tiered hierarchy

Question 279

Traffic Flows Datacenter: North-South?

Answer 279

North: traffic that is exiting the datacenter
South: traffic that is entering the datacenter

Question 280

Traffic Flows Datacenter: East-west?

Answer 280

refers to dataflows within a datacenter

Question 281

deterministic ?

Answer 281

very organized and orderly requires an electronic token to transmit.

Like a student raising his hand and getting called on

Question 282

contention based ?

Answer 282

very chaotic and can transmit whenever possible

the problem with this method is you have collisions

Question 283

what sort of network access method does ethernet use ?

Answer 283

ethernet uses contention based network access

Question 284

how does ethernet prevent collisions?

Answer 284

ethernet prevents collisions with something known as CSMA/CD

Question 285

Carrier sense multiple access collision detection CSMA/CD?

Answer 285

prevents collisions by using carrier sensing to defer transmissions until no other stations are transmitting

Question 286

Collision domain ?

Answer 286

each area of the network that shares a single segment is known as a collision domain

Question 287

What does ethernet switching do for our networks?

Answer 287

increases scalability of a network by creating multiple collision domains

Question 288

what does bandwidth mean in networking ?

Answer 288

measures how many bits the network can transmit per second

Question 289

what is the maximum distance of copper cables ?

Answer 289

100 meters

Question 290

what are the metrics of CAT 6 cables?

Answer 290

Using CAT 6 at 100 meters will limit the speed from 10 Gbps to 1 Gbps

Question 291

using CAT 6 at 55 meters what sort of speeds can you get ?

Answer 291

Using CAT 6 at under 55 meters can reach 10 Gbps of speed

Question 292

what are the distances typically associated with multi mode fiber ?

Answer 292

Multimode fibers deal with shorter distances something in the 200 to 500 meter range

Question 293

should we use multimode fiber or single mode fiber for long distances ?

Answer 293

use single mode fiber for long distances

Question 294

what sort of fiber should we use for short distances ?

Answer 294

you need to use multimode fiber for short distances

Question 295

Network Devices: Hub

Answer 295

also known as a multiport repeater it is a layer 1 device that connects multiple network devices and workstations

Question 296

what are the three types of hubs ?

Answer 296

1. passive hub
2. active hub
3. smart hub

Question 297

Hubs: passive hub ?

Answer 297

repeats single with no amplification

Question 298

Hubs: active hub ?

Answer 298

repeats signal with amplification
used for long distances

Question 299

Hubs: smart hubs ?

Answer 299

active hub with enhanced features like snmp

Question 300

Network devices: bridge ?

Answer 300

analyzes source MAC addresses and makes intelligent forwarding decisions based on the destination MAC in the frames

Question 301

Network Devices: switch ?

Answer 301

also known as a multiport bridge, it is a layer 2 device that connects multiple network segments together. A switch is essentially a multi-port bridge

Question 302

Network devices: Router?

Answer 302

Layer 3 device that connects multiple networks and makes forwarding decisions based on logical network information

Question 303

Network Devices: layer 3 switch ?

Answer 303

makes layer 3 routing decisions and then interconnects entire networks not just network segments

Question 304

what layer does a switch operate on and what does it focus on ?

Answer 304

layer 2 device focused on MAC addresses

Question 305

what layer does a router operate on and what is it focused on ?

Answer 305

layer three device focused on IP addresses

Question 306

what are the additional features switches can offer?

Answer 306

VLAN’s
Trunking
STP
Link aggregation
Power over ethernet
Port monitoring
User authentication

Question 307

Switching Features: Link Aggregation ?

Answer 307

combines multiple physical connections into a single logical connection to minimize or prevent congestion

Question 308

what is the standard for link aggregation ?

Answer 308

Link aggregation standard IEEE 802.3ad

Question 309

what problem does link aggregation solve in a network ?

Answer 309

link aggregation is a solution for the problem of congestion. congestion can occur when all ports operate at the same speed

Question 310

are switches full duplex or half duplex ?

Answer 310

switches are full duplex which means every port can operate at 100mbps

Question 311

what is the standard for power over ethernet?

Answer 311

802.3at

Question 312

Power over ethernet?

Answer 312

supplies electrical power over ethernet and requires cat 5 or higher copper cable.

the benefit of this is instead of needing two separate cables for power and data you can use one for booth

Question 313

Port monitoring or mirroring ?

Answer 313

makes a copy of all traffic destined for a port and sends it to another port

Question 314

what is out of band management ?

Answer 314

keeps all network configuration devices on a separate network

Question 315

first hop redundancy ?

Answer 315

FHRP is used to prevent network failure at a default gateway. This is achieved by configuring multiple routers with the same IP address and Mac address, thus presenting an illusion of a single virtual router to the hosts in a Local Area Network (LAN).

this helps with redundancy

Question 316

MAC filtering ?

Answer 316

permits or denies traffic based on a devices MAC address

Question 317

Traffic filtering ?

Answer 317

permits or denies traffic based on IP address or application ports

Question 318

what is IT governance ?

Answer 318

It governance is used to provide a comprehensive security management framework for the org

Question 319

How is IT governance achieved ?

Answer 319

1. Policies
2. standards
3. baseline
4. Guidelines
5. Procedures

Question 320

what is a security policy ?

Answer 320

defines the role of security inside of an org and establishes the desired end state for the security program

Question 321

what are the three different categories for security policies ?

Answer 321

1. organizational
2. system specific
3. issue specific

Question 322

what is an organizational policy ?

Answer 322

provides frameworks to meet the business goals and define the roles, responsibilities, and teams associated with it

Question 323

what are system specific policies ?

Answer 323

these address the specific technology, application, network or computer

Question 324

what are issue specific policies ?

Answer 324

addresses a specific security issue such as email privacy, employee termination procedures, or other specific issues

Question 325

what are standards ?

Answer 325

implements a policy in an org

Question 326

Baseline ?

Answer 326

creates a reference point in network architecture and design

Question 327

Guideline ?

Answer 327

recommended action that allows for exceptions and allowances in unique situations and recommends actions

Question 328

Procedures ?

Answer 328

detailed step-by-step instructions created to ensure personnel can perform a given task or series of actions

Question 329

Change management ?

Answer 329

structured way of changing the state of a computer system, network, or IT procedure

Question 330

incident response plan ?

Answer 330

contains instructions on how to help network and system admins, detect, respond to, and recover from network security incidents

Question 331

incident response plans are broken into 6 core phases

Answer 331

1. preparation
2. identification
3. containment
4. Eradication
5. recovery
6. lessons learned

Question 332

Disaster recovery plan ?

Answer 332

Documents how an org can quickly resume work after an unplanned incident

Question 333

Business continuity plan ?

Answer 333

outlines how a business will continue operating during an unplanned disruption in service

Question 334

System life cycle plan ?

Answer 334

describes the approach to maintaining an asset from creation to disposal

Question 335

what is the 5 phase lifecycle used for all of our systems and networks.

Answer 335

1. planning
2. design
3. transition
4. operations
5. retirement

Question 336

standard operating procedure ?

Answer 336

a step-by-step instructions compiled by an org to help its employees carry out routine operations

Question 337

Password policies ?

Answer 337

a set of rules created to improve computer security by motivating users to create and properly store secure passwords

Question 338

acceptable use policies?

Answer 338

a set of rules that restricts the ways in which a network resource may be used and sets guidelines on how it should be used

Question 339

BYOD policies ?

Answer 339

allows employees to access enterprise networks and systems using there personal devices

Question 340

remote access policies ?

Answer 340

a document which outlines and defines acceptable methods of remotely connecting to the internal network

Question 341

Onboarding policies ?

Answer 341

A documented policy that describes all the requirements for integrating a new hire into the company and its cultures

Question 342

Offboarding policy ?

Answer 342

A documented policy that covers all the steps to successfully part ways with an employee who’s leaving the company

Question 343

Security policies ?

Answer 343

a document that outlines how to protect the organizations systems, networks and data from threats

Question 344

DLP policies?

Answer 344

A document defining how orgs can share and protect data

Goal of a data loss prevention policy minimizes accidental or malicious data loss

Question 345

NDA agreement ?

Answer 345

Defines what data is confidential and cannot be shared outside of the relationship

Question 346

Memorandum of understanding MOU?

Answer 346

non-binding agreement between two or more organizations to detail what common actions they intend to take

Question 347

Service level agreement SLA ?

Answer 347

Documents the quality, availability, and responsibilities agreed upon by a service provider and client

Question 348

what is network management ?

Answer 348

the process of administering and managing computer networks

Question 349

what is a physical network diagram ?

Answer 349

shows the actual physical arrangement of the components that make up the network

Question 350

What is a Logical Network Diagram?

Answer 350

illustrates the flow of data across a network and shows how devices communicate with each other

Question 351

what is a radio frequency wireless site survey ?

Answer 351

Planning and designing of a wireless network to deliver the required wireless solution

Question 352

Wired site survey?

Answer 352

determines If a site has the right amount of power, space, and cooling to support a new upgrade or installation

Question 353

what are baseline configs?

Answer 353

set of specifications for an information system, or a configuration item within a system, that has been formally reviewed and agreed on

Question 354

what is network performance monitoring ?

Answer 354

monitors the performance from the end user’s workstation to the final destination they are trying to reach

Question 355

what are the three key metrics for network performance ?

Answer 355

1. latency
2. Bandwidth
3. Jitter

Question 356

what is Latency ?

Answer 356

time it takes for data to reach its destination across the network. latency is reported in milliseconds

Question 357

what is bandwidth ?

Answer 357

maximum rate of data transfer across a given network.

Question 358

what is throughput ?

Answer 358

this is the actual measure of how much data is successfully transferred from the source to the destination

Question 359

explain Jitter ?

Answer 359

when a time delay in the sending of data packets over a network connection occurs

Question 360

what do sensors do for us in our networks ?

Answer 360

monitor a device’s temperature, CPU usage, and memory which could indicate if it is operating properly or is about to fail

Question 361

what is a minor temperature threshold ?

Answer 361

monitor a devices temperature CPU usage and memory which could indicate if it is operating properly or if it is about to fail

Question 362

what is a major temperature threshold ?

Answer 362

used to set off an alarm when temperature reaches dangerous conditions.

Question 363

what are the two ways to measure data in our networks ?

Answer 363

In order to measure traffic in our network we can either use full packet capture or netflow data

Question 364

what is full packet capture ?

Answer 364

captures the entire packet, including the header and the payload for all traffic entering and leaving a network

Question 365

what is flow analysis ?

Answer 365

relies on a flow connector to record the metadata and statistics about network traffic rather then recording each frame

Question 366

what is netflow?

Answer 366

defines a particular traffic flow based on the different packets that share the same characteristics.

Question 367

Zeek?

Answer 367

passively monitors a network like a sniffer but only logs full packet capture of data of potential interest

Question 368

MRTG multi router traffic grapher?

Answer 368

creates graphs showing traffic flows through the network interfaces of routers and switches by polling the appliances using snmp

Question 369

Interface statistics: flush

Answer 369

used to count selective packet discards SDP that have occurred

Question 370

Interface statistics: selective packet discards

Answer 370

drops low priority packets when the CPU is too busy so it can save capacity for higher priority packets as a form of Qos

Question 371

Interface statistics: runt

Answer 371

an ethernet frame that is less than 64 bytes in size

Question 372

Interface statistics: giant

Answer 372

any ethernet frame that exceeds the 802.3 frame size of 1518 bytes

Question 373

Interface statistics: throttle

Answer 373

occurs when the interface fails to buffer the incoming packets

Question 374

Interface statistics: CRC

Answer 374

CRC number of packets received that failed the cyclic redundancy checksum or CRC check upon receipt

Question 375

Interface statistics: Frame

Answer 375

used to count the number of packets where a CRC error and a non-integer number of octets was received

Question 376

Interface statistics: ignored

Answer 376

used to count the number of packets that the interface ignored since the hardware interface was low on internal buffers

Question 377

Interface statistics: underrun

Answer 377

number of times the sender has operated faster then the router can handle, causing buffers or packets dropped

Question 378

Interface statistics: babble

Answer 378

used to count any frames that are transmitted and are larger than 1518 bytes

Babble is for transmission giant is for received

Question 379

Interface statistics: late collision

Answer 379

used to count the number of collision that occur after the interface has started transmitting its frame

Question 380

Interface statistics: deferred

Answer 380

used to count the number of frames that were transmitted successfully after waiting because the media was busy

Question 381

Interface statistics: output buffer failure

Answer 381

number of times a packet was not output from the output hold queue because of a shortage of shared memory

Question 382

what does the CIA triad stand for ?

Answer 382

1. confidentiality
2. integrity
3. availability

Question 383

how do we ensure confidentiality in our networks ?

Answer 383

keep data private and safe using encryption and authentication to access resources

Question 384

explain what encryption does for us in our networks ?

Answer 384

ensures the data can only be read or decoded by the intended recipient

Question 385

what is symmetric encryption ?

Answer 385

sender and receiver use the same key to encrypt and decrypt a message

Question 386

what are the three main types of symmetric encryption out there ?

Answer 386

1. DES
2. Triple DES
3. AES

Question 387

what is Data encryption standard DES?

How long is the key for DES ?

Is DES considered weak or strong encryption by today’s standards ?

Answer 387

a 56-bit encryption key to secure data. today this is considered weak encryption

Question 388

explain Triple DES

how many keys does it use?

Answer 388

uses three 56-bit keys which gives a total key strength of 168 bits

Question 389

what is the Advanced Encryption Standard or AES?

what keys is it available in?

Answer 389

Preferred symmetric encryption standard today and is available in 128-bit, 192-bit, and 256-bit keys

Question 390

which is faster symmetric or asymmetric encryption ?

Answer 390

Symmetric encryption is almost a 1000x faster than asymmetric encryption

Question 391

what sort of overhead is needed when an org is using symmetric encryption ?

Answer 391

The overhead with symmetric encryption is making sure that all the users have the key who need to use it

Question 392

what is asymmetric encryption ?

Answer 392

Sender and receiver use different keys to encrypt and decrypt a message

Question 393

Public key infrastructure or PKI?

Answer 393

gives secure email exchanges and web browsing and solves the problem of having to distribute the keys ahead of time

Question 394

how does PKI help with email security ?

Answer 394

PKI is where we encrypt the data from an email sender to an email receiver

Question 395

what does integrity mean inside our networks ?

Answer 395

ensures data was not modified in transit and verifies it came from its original source

Question 396

how do we ensure we have integrity in our networks ?

Answer 396

We ensure we have integrity in our networks and applications by using hashing

Question 397

what is hashing ?

Answer 397

runs a string of data through an algorithm, creates a hash that serves as a unique individual fingerprint for a file or data set

Question 398

what does availability mean in our networks ?

Answer 398

measures data accessibility and is increased by designing redundant networks

Question 399

what is a threat ?

Answer 399

a person or event that has the potential for impacting a valuable resource in a negative manner

Question 400

what is a denial of service attack ?

Answer 400

occurs when one machine continually floods a victim with request for services

Question 401

explain a TCP SYN flood ?

Answer 401

occurs when an attacker initiates multiple TCP sessions but never completes them

Question 402

smurf attack ?

Answer 402

occurs when an attacker sends a ping to a subnet broadcast address with a source IP spoofed to be that of the victim server

Question 403

distributed denial of service attack ?

Answer 403

occurs when an attacker uses multiple computers to ask for access to the same server at the same time

Question 404

botnet ?

Answer 404

a collection of compromised computers under the control of a master node

Question 405

zombie ?

Answer 405

any of the individually compromised computers within a botnet

Question 406

explain an on path or man in the middle attack

Answer 406

occurs when an attacker puts themselves between the victim and the intended destination

Question 407

session hijacking ?

Answer 407

occurs when an attacker guesses the session ID that is in use between a client and a server and takes over the authenticated session

Question 408

DNS poisioning

Answer 408

occurs when an attacker manipulates known vulnerabilities within DNS to reroute traffic from one site to a fake version of the site

Question 409

what was created to combat DNS poisioning ?

Answer 409

DNSSEC was created to combat DNS poisioning

Question 410

what is DNSSEC?

Answer 410

uses encrypted digital signatures when passing DNS information between servers to help protect it from poisoning

Question 411

explain a rogue DHCP server

Answer 411

a DHCP server on a network which is not under the administrative control of the network admins

Question 412

spoofing ?

Answer 412

occurs when an attacker masquerades as another person by falsifying their identity

Question 413

IP spoofing ?

Answer 413

modifying the source address of an IP packet to hide the identity of the sender or impersonate another client

Question 414

what layer of the OSI model does IP spoofing occur

Answer 414

IP spoofing is focused at layer 3 of the OSI model

Question 415

MAC spoofing ?

Answer 415

changing the MAC address to pretend the use of a different network interface card or device

Question 416

what is MAC filtering ?

Answer 416

relies on a list of all known and authorized MAC addresses

Question 417

what is ARP spoofing ?

Answer 417

sends falsified ARP messages over a local area network

Question 418

what is the purpose of ARP?

Answer 418

the purpose of ARP is to create a binding between a MAC address and an IP address inside of a LAN

Question 419

how do we prevent ARP poisoning in a network ?

Answer 419

to prevent ARP poisoning set up good VLAN segmentation within your network

Question 420

what is VLAN hopping ?

Answer 420

ability to send traffic from one VLAN to another, bypassing the VLAN segmentation you have configured with your layer 2 networks

Question 421

what are the two ways attackers can accomplish VLAN hoping ?

Answer 421

1. Double tagging
2. Switch spoofing

Question 422

VLAN hoping: Double tagging ?

Answer 422

connecting to an interface on the switch using access mode with the same VLAN as the native untagged VLAN on the trunk

Question 423

VLAN hoping switch spoofing ?

Answer 423

Attempting to conduct a dynamic trunking protocol DTP negotiation

Question 424

what is malware ?

Answer 424

designed to infiltrate a computer system and possibly damage it without the users consent or knowledge

Question 425

what is a virus ?

Answer 425

made up of malicious code that is run on a machine without the users knowledge and infects it whenever that code is run

Question 426

what is a worm ?

Answer 426

a piece of malicious software that can replicate itself without user interaction

Question 427

explain a trojan horse ?

Answer 427

a piece of malicious software disguised as a piece of harmless or desirable software

Question 428

ransomeware?

Answer 428

restricts access to a victims computer system or files until a ransom or payment is received

Question 429

what is spyware?

Answer 429

gathers information about you without your consent

Question 430

what is a rootkit ?

Answer 430

designed to gain administrative control over a computer system or network device without being detected

Question 431

rogue access point ?

Answer 431

a wireless acess point that has been installed on a secure network without authorization from a local network admin

Question 432

Shadow IT?

Answer 432

use of IT systems, devices, software applications, or services without the explicit approval of the IT department

Question 433

Evil Twin Attack ?

Answer 433

wireless access point that uses the same SSID as your own network

Question 434

De-Authentication attack ?

Answer 434

attempt to interupt communication between an end user and the wireless access point

Question 435

Wireless interception ?

Answer 435

captures wireless data packets as they go across the airwaves

Question 436

what is social engineering ?

Answer 436

any attempt to manipulate users to reveal confidential information or perform actions detrimental to a systems security

Question 437

what is phising ?

Answer 437

sending an email in an attempt to get a user to click on it

Question 438

Spearphising ?

Answer 438

more targetd form of phising

Question 439

what is whaling?

Answer 439

focused on key executives within an org or other key leaders, executives and managers in the company.

Question 440

what is tailgating ?

Answer 440

entering a secure portion of the organizations building by following an authorized person into the area without their knowledge or consent

Question 441

what is an insider threat ?

Answer 441

an employee or other trusted insider who uses their authorized network access in unauthorized ways to harm the company

Question 442

what is a posture assessment ?

Answer 442

asesses cyber risk posture and exposure to threats caused by misconfiguration and patching delays

Question 443

what are the 4 main steps of a security posture assessment ?

Answer 443

1. Define mission critical components
2. identify strengths weaknesses and security issues
3. strengthen your position
4. stay in control

Question 444

what is a business risk assessment ?

Answer 444

used to identify understand and evaluate potential hazards in the workplace

Question 445

what is a process assessment ?

Answer 445

the disciplined examaniation of the processes used by the org against a set of criteria

Question 446

what is a vendor assessment ?

Answer 446

the assessment of a prospective vendor to determine if they can effectively meet the obligations and the needs of the business

Question 447

what is least privilege ?

Answer 447

using the lowest level of permissions or privielegs needed in order to complete a job function or admin task

Question 448

Discretionary access control or DAC ?

Answer 448

• an access method where access is determined by the owner of the resource

Question 449

what are the two main challanges when using DAC?

Answer 449

1. every object in a system has to have an owner
2. Each owner must determine the access rights and permissions for each object

Question 450

Mandatory access control MAC?

Answer 450

An access control policy where the computer system gets to decide who gets access to what objects

Question 451

Role based access control RBAC

Answer 451

An access control model that is controlled by the system but focuses on a set of permissions versus an individual permission

Creating groups makes it easy to control permissions based around actual job functions

Question 452

Zero trust ?

Answer 452

a security framework that requires users to be authenticated and authorized before being granted access to applications and data

Question 453

what are the 4 key principles you need to follow to implement zero trust in your network ?

Answer 453

1. Reexamine all default access controls
2. Employ a variety of prevention techniques and defense in depth
3. Enable real-time monitoring and controls to identify and stop malicious activity quickly
4. Ensure the networks zero-trust architecture aligns to a broader security strategy

Question 454

what is defense in depth ?

Answer 454

cybersecurity approach in which a series of defensive mechanisms are layered in order to protect valuable data and information

Question 455

explain a DMZ ?

Answer 455

a perimeter network that protects an organizations internal local area network from untrusted traffic

only allows people from the outside internet to access certain resources within your network

Question 456

explain a screened subnet ?

Answer 456

subnet in the network architecture that uses a single firewall with three interfaces to connect three dissimilar networks

Used in networks that have both public and private areas, a screened subnet lets users access the internet without exposing the local area network to internet-based cyber attacks or data breaches. It does this by establishing a network between an internal network and an external/presumed hostile network, such as the internet. This ensures that there is no single vulnerable point that could potentially compromise the entire enterprise network.

It uses three network interfaces:

Interface 1 is the public interface connected to the internet.
Interface 2 connects to the demilitarized zone (DMZ) to which hosted public services are attached.
Interface 3 connects to the intranet to provide access to and from internal networks.
The subnet’s main purpose is to isolate the DMZ and its publicly accessible resources from the intranet, thereby minimizing external attention and possible attacks on that subnet. The architecture makes it more difficult to attack the intranet, especially when a properly configured firewall is combined with the use of private IP addresses on one or both of these subnets. Even if the firewall itself is compromised, an attacker won’t be able to access the intranet.

Question 457

Separation of duties

Answer 457

prevents fraud and abuse by distributing carious tasks and approval authorities across a number of different users

Question 458

MFA?

Answer 458

authenticates or proves an identity using more than one method

Question 459

MFA: something you know?

Answer 459

a. Usernames
b. Passwords
c. PIN
d. Answers to questions

Question 460

MFA: something you have ?

Answer 460

a. smartcards
b. RSA key fobs
c. RFID tags

Question 461

MFA: something you are?

Answer 461

a. fingerprints
b. Retina scans
c. Voice prints

Question 462

MFA: something you do?

Answer 462

a. How you sign your name
b. How you draw a pattern

Question 463

MFA: Somewhere you are?

Answer 463

a. Geotagging
b. geofencing

Question 464

Authentication ?

Answer 464

the process of determining whether someone or something is who or what it claims to be

Question 465

LDAP?

Answer 465

validates a username and password combination against an LDAP server as a form of authentication

The Lightweight Directory Access Protocol is a common method of accessing data over the network.

Question 466

Kerberos?

Answer 466

focused on authentication and authorization with a windows domain environment

Question 467

Remote authentication dial-in user service RADIUS

Answer 467

provides centralized administration of dial-up, VPN, and wireless network authentication

Question 468

Terminal access controller access control system plus TACACS+

Answer 468

used to perform the role of an authenticator in an 802.1x network

Question 469

802.1x

Answer 469

a standardized framework that’s used for port-based authentication on both wired and wireless networks

Question 470

There are three roles required to authenticate with 802.1x ?

Answer 470

1. supplicant
   a. Device or user requesting access to the network
2. authenticator
   a. Switch wireless access point
3. Authentication server
   a. Centralized device that performs the authentication

Question 471

extensible authentication protocol EAP?

Answer 471

allows for numerous different mechanisms of authentication

Question 472

EAP-MD5?

Answer 472

utilizes simple passwords and the challenge handshake authentication process to provide remote access authentication

Question 473

EAP-TLS

Answer 473

uses public key infrastructure with a digital certificate being installed on both the client and the server

Question 474

EAP-TTLS

Answer 474

requires a digital certificate on the server and a password on the client for its authentication

Question 475

EAP-FAST

Answer 475

uses a protected access credential to establish mutual authentication between devices

Question 476

PEAP

Answer 476

uses server certificates and Microsoft’s AD databases to authenticate a clients password

Question 477

Network access control NAC

Answer 477

ensures a device is scanned to determine its current state of security prior to being allowed network access

Question 478

persistent agent

Answer 478

a piece of software installed on a device requesting access to the network

Question 479

Non-persistent agent

Answer 479

requires the users to connect to the network and go to a web based captive portal to download an agent on their devices

Question 480

what is one of the most common network access control standards ?

Answer 480

IEEE 802.1x

Question 481

where is IEEE 802.1x used ?

Answer 481

used in port-based network access control

Question 482

NAC: Time-Based

Answer 482

defines access periods for given hosts using a time-based schedule / only logging in during approved times

Question 483

NAC: Location-based

Answer 483

evaluates the location of the endpoint requesting access using IP or GPS geolocation

Question 484

NAC: Role based adaptive NAC

Answer 484

reevaluates a device’s authentication when its being used to do something / looking at the role of the device and figure out if it is doing something it should or should not be able to do

Question 485

NAC: Rule-based

Answer 485

uses a complex admission policy that might enforce a series of rules with the use of logical statements

Question 486

Efuse

Answer 486

an electronic detection mechanism that can record the version of the IOS used by a switch

Question 487

what does OSI stand for ?

Answer 487

open systems interconnection model

Question 488

what is layer 1 of the OSI model ?

Answer 488

layer 1 is the physical layer

Question 489

describe what happens at layer 1 the physical layer of the OSI model

Answer 489

• Where transmission of bits across the network occurs and includes physical and electrical network characteristics
• Data is transferred in bytes at this layer series of 1s and 0s

Question 490

what does the physical layer decide about the network ?

Answer 490

The physical layer also decides the topology of the network

Question 491

what is an issue to be aware of at layer 1

Answer 491

Another issue to be aware of at layer 1 is how is communication synchronized

Question 492

what is asynchronous communication ?

Answer 492

Asynchronous communication is something like a voicemail, the communication happens out of sync or out of time

uses start and stop bits to indicate when transmissions occur from the sender to the receiver

Question 493

what is synchronous communication ?

Answer 493

uses a reference clock to coordinate the transmissions by both the sender and receiver

Question 494

what is broadband ?

Answer 494

divides our bandwidth into separate channels

Question 495

what is baseband communication ?

Answer 495

uses all available frequencies on a medium (cable) to transmit data

A telephone is a good example of baseband communication

Aka using all the bandwidth allocated to that phone line

Baseband uses a reference clock

Wired home ethernet network is also going to use baseband

Question 496

what is TDM or time division multiplexing ?

Answer 496

Each session takes a turn using time slots to share the medium between users

Question 497

Statistical time-division multiplexing

Answer 497

Dynamically allocates the time slots on an as-needed basis

Question 498

Frequency division multiplexing

Answer 498

Divides the medium (that cable) into channels based on the frequency and each session is transmitted over different channel

Question 499

what is multiplexing ?

Answer 499

multiplexing is getting more out of a limited network

Question 500

what are some examples of devices at the physical layer ?

Answer 500

Cable

Ethernet

Coaxial

Hubs

Access points

Media converters

Layer 1 devices simple repeating what they are told

Question 501

what is the main function of the data link layer ?

Answer 501

Packages data into frames and transmits those frames on the network

Question 502

what is media access control or MAC ?

Answer 502

Physical addressing system of a device which operates on a logical topology

Uses a 48 byte address assigned to a network interface card

Question 503

how are the digits in a MAC address divided ?

Answer 503

The first 6 digits in a mac address are the vendor code the second 6 digits are the unique value

Question 504

Logical Link Control LLC?

Answer 504

provides connection services and allows acknowledgment of receipt of messages

Question 505

what does LLC or logical link control provide ?

Answer 505

LLC provides basic error control functions

Question 506

what is run on the application layer

Answer 506

services /apps
web browsers
files

Question 507

what is run on the presentation layer

Answer 507

encoding
compression
encryption

Question 508

what is the session layer used for ?

Answer 508

managing sessions

Question 509

explain protocols in laymen terms

Answer 509

a set of rules or a way for computers to do things

Question 510

Please do not throw sasuage pizza away

Answer 510

Phsical
datat link
network
transport
session
presentation
application

Question 511

in the TCP/IP model what are the three layers from the OSI model that make up the application layer

Answer 511

application
presentation
session

Question 512

what is the order of the IP protocl stack we use today

Answer 512

Application
transport
network Data link
phsical

Question 513

what are the two most common protocols in the transport layer of the TCP/IP protocol stack

Answer 513

TCP & UDP

Question 514

what protocl does DNS use ?

Answer 514

UDP

Question 515

what layer of the TCP/IP protocol stack does IP addresses operate ?

Answer 515

the network layer or internet layer

Question 516

what do we call information transmitted at the internet layer of the TCP/IP protocol stack ?

Answer 516

Packets

Question 517

what networking device is looking at the layer 3 or network layer packets ?

Answer 517

routers

Question 518

what is layer 2 of the TCP/IP protocol stack

Answer 518

data link layer

network

internet layer

Question 519

what is ARP used for ?

Answer 519

arp is used to map IP address’s to MAC adresses’s

Question 520

what do we call information that is sent over the data link layer of the tcp/ip model

Answer 520

frames

Question 521

what layer of the TCP/IP protocol stack does encapsulation start?

Answer 521

the application layer

Question 522

what layer of the tcp/ip protocol stack does decapsulation start ?

Answer 522

the phsical layer

Question 523

what is a demarcation point ?

Answer 523

a spot where we connect our network to an internet service provider

Question 524

what does GRE stand for ?

Answer 524

Generic routing encapsulation

Question 525

what is an overlay network ?

Answer 525

an overlay network is a computer network that is layered on top of another network

Question 526

what does an underlay network represent ?

Answer 526

underlay network represents the actual interfaces and paths that are being used as traffic is being forwarded on networks

Question 527

topology ?

Answer 527

how networks are layed out.

Question 528

what are some things we should keep in mind when troubleshooting network issues ?

Answer 528

1. device configuration reviews
2. routing tables
3. interface status
4. VLAN assignments
5. Network performance baselines

Question 529

what do most networking devices have for configurations ?

Answer 529

most network devices have two configs a startup config and a running config

Question 530

Networking devices: startup config ?

Answer 530

stored in NVRAM and contains the commands needed to initially configure a router

Question 531

Networking devices: running config?

Answer 531

actively being used by the router at that moment

Question 532

what command can we use to see the startup config for a router ?

Answer 532

show startup-config

Question 533

what command can we use to see the running config for a router ?

Answer 533

show running-config

Question 534

how can we display the routing table on a windows machine ?

Answer 534

“route print”

Question 535

how would we display the routing table on a linux command line ?

Answer 535

route - n

Question 536

Net Troubleshoot: VLAN Assignment / Tagging?

Answer 536

practice of segmenting an IT organazations network, seperating users into respective network sections

Question 537

what is a network performance baseline ?

Answer 537

defines the normal working conditions of an enterprise network infastructure

Question 538

What is the purpose of the DHCP service ?

Answer 538

assigns devices with an IP address and also provides them a subnet mask, default gateway and DNS server.

Question 539

What is the purpose of the DNS service ?

Answer 539

converts domain names to IP addresses using hierarchical and decentralized system of naming

Question 540

what is a DNS zone transfer ?

Answer 540

sharing of information between DNS servers about which domain names they have and there associated IP addresses

Question 541

what is the purpose of the Network Time Protocol or NTP ?

Answer 541

Synchronizes clocks between systems communicating over a packet switched variable latency data network

Question 542

what must DHCP provide for each client to effectively access the internet?

Answer 542

DHCP must provide and IP address, subnet mask, default gateway and DNS server to each client to effectively access the internet

Question 543

Explain a DHCP reservation ?

Answer 543

DHCP reservations allow the DHCP server to pre-set an IP address to a specific client based on its MAC address.

DHCP reservations are usually used with servers or printers on your internal network and are rarely used with end-user devices

Question 544

What does DHCP do for our networks ?

Answer 544

provides an IP address to every machine on the network and eliminates configuration errors

Question 545

DHCP: Scope ?

Answer 545

a list of valid IP addresses available for assignment or lease to a client computer or endpoint device on any given subnet

Question 546

DHCP: Reservation ?

Answer 546

excludes some IP addresses being handed out to devices unless they meet a certain condition

Question 547

As a network admin how does DHCP help us out ?

Answer 547

with DHCP we can automate setup of all our devices when they join the network

Question 548

DHCP: what happens when a device joins the network ?

Answer 548

when a device joins the network its going to do what we call a discovery “hey DHCP server I need an IP address”

Question 549

DHCP: what are the 4 steps of the DHCP process ?

Answer 549

1. Discover
2. Offer
3. Request
4. Acknowledge

D.O.R.A

Question 550

DHCP: what 4 pieces of information do network clients get from DHCP?

Answer 550

1. IP address
2. Subnet Mask
3. Default Gateway IP
4. DNS Server IP

Question 551

DHCP relay ?

Answer 551

DHCP relay is used when the client device and the DHCP server are not located on the same subnet or network

Question 552

Does DHCP operate using TCP or UDP

Answer 552

UDP

Question 553

DNS: What does the domain name service help us do ?

Answer 553

helps network clients find a website using human-readable hostnames instead of numeric IP addresses

Question 554

DNS: what are some examples of fully qualified domain names or FQDN ?

Answer 554

Examples of fully qualified domain names

www.diontraining.com

Mail.diontraining.com

Ftp.diontraining.com

Question 555

What are the different levels of the DNS hierarchy?

Answer 555

1. Root - Answers requests in the root zone
2. Top-level domain - .com .net
3. Second-level domain - Diontraining.com google.com
4. Subdomain - Support.diontraining.com
5. Host - Refers to a specific machine

Question 556

DNS Records: A ?

Answer 556

links a hostname to an IPV4 address

Question 557

DNS Records: AAAA?

Answer 557

links a hostname to an IPv6 address

Question 558

DNS Records: CNAME?

Answer 558

points a domain name to another domain or subdomain

essentially a domain redirect

Question 559

DNS Records: MX?

Answer 559

Directs email to a mail server

Question 560

DNS Records: SOA?

Answer 560

stores important information about a domain or zone ?

Question 561

DNS Records: PTR?

Answer 561

corelates an IP address with a domain name

These are essentially the opposite of A records

Question 562

DNS Records: TXT?

Answer 562

Adds text into the DNS record

Question 563

DNS Records: SRV?

Answer 563

specifies a host and port for a specific service

Question 564

DNS Records: NS?

Answer 564

Type of DNS server that stores all the DNS records for a given name

Question 565

DNS: Zone transfer ?

Answer 565

sends DNS records data from the primary nameserver to the secondary nameserver.

Zone transfers use the TCP protocol to transfer data

Question 566

DNS: reverse DNS lookup ?

Answer 566

determines what the domain name is for a given IP address.

Question 567

DNS: forward lookup ?

Answer 567

uses DNS to find the IP address for a given network

Question 568

Internal DNS ?

Answer 568

allows cloud instances on the same network to access each other using internal DNS names

Question 569

External DNS?

Answer 569

records created around the domain names from a central authority and used on the public internet

An external DNS is a publicly accessible third-party domain name server that’s generally open for anyone on the internet to access and update. External DNS allows you to query for the IP address of a domain. An external DNS provider is also known as a public DNS provider.

Question 570

DNS: Time to Live TTL

Answer 570

tells the DNS resolver how long to cache a query before requesting a new one

Question 571

DNS: Recursive lookup?

Answer 571

DNS server communicates with several other DNS servers to hunt down the IP address and return to the client

Question 572

NTP?

Answer 572

synchronizes clocks between systems communicating over a packet-switched variable-latency data network

Question 573

what is the easiest way to describe NTP?

Answer 573

Essentially keeps all the devices on the same time

Question 574

what port and protocol does NTP use?

Answer 574

NTP data is going to be sent over UDP using port 123

Question 575

wireless analyzer

Answer 575

ensures you have the proper coverage and helps prevent overlap between wireless access points coverage zones and channels

Question 576

protocol analyzer

Answer 576

used to capture and analyze signals and data traffic over a communications channel Example wireshark

Question 577

Packet capturing tool

Answer 577

used to capture packets running over a network connection in real time and then save them for later analysis

Question 578

What is wireshark ?

Answer 578

wireshark is both a protocol analyzer and has packet capture functionality

Question 579

What is a bandwidth speed test ?

Answer 579

verifies the real world throughput from a client device all the way out to the internet and back

this is like the WIFI speed tests you do at work

Question 580

what is real world throughput ?

Answer 580

the speed from your client to the endpoint device and back.

Question 581

IPERF?

Answer 581

gathers an active measurement of the maximum achievable bandwidth of an IP based network

Iperf is a tool for network performance measurement and tuning. It is a cross-platform tool that can produce standardized performance measurements for any network. Iperf has client and server functionality, and can create data streams to measure the throughput between the two ends in one or both directions

Question 582

NetFlow Analyzer ?

Answer 582

performs monitoring troubleshooting and in-depth inspection, interpretation and synthesis of traffic flow data

Question 583

TFTP?

Answer 583

protocol for exchanging files between two TCP/IP machines

port 69

Question 584

What is the ping command used for ?

Answer 584

ping checks the connectivity between two devices and usually is used to see if a device is up and is often used for network troubleshooting

Question 585

how would you ping an IPV6 address ?

Answer 585

ping can use IPV6 with the -6 option.

Question 586

traceroute / tracert

Answer 586

displays the path between device and its destination showing the source and destination IP address for each hop along the way

Question 587

what is a hop when we are talking about traceroute ?

Answer 587

a hop is any router or firewall that is in the path of the transmission from the client to the destination

Question 588

what is the purpose of the ipconfig command ?

Answer 588

Ipconfig displays all of the current TCP/IP network config values and refreshes DHCP and DNS settings for a windows client/ server

Question 589

using Ipconfig how would we release the current IP address ?

Answer 589

ipconfig /release

Question 590

how would we attempt to get a new IP address using the ipconfig command ?

Answer 590

Ipconfig /renew

Question 591

how would we attempt to get all the IP info and DHCP info using the Ipconfig command ?

Answer 591

Ipconfig /all

Question 592

what is the equivalent of IP config on a linux system

Answer 592

ifconfig

Question 593

how do we learn more about a specific interface with ifconfig ?

Answer 593

ifconfig -v eth0

Question 594

what does the IP command do on a linux operating system ?

Answer 594

Ip – assigns an address to a network interface or configures network interface parameters on a Unix, Linux, or OSX operating system

Question 595

what is the nslookup tool used for ?

Answer 595

used to query the DNS to provide the mapping between domain names and IP addresses or other DNS records

Question 596

how would you do a forward lookup using the nslookup tool ?

Answer 596

nslookup google.com

Question 597

how would we do a reverse lookup using the nslookup tool ?

Answer 597

nslookup 8.8.8.8

Question 598

explain the dig command

Answer 598

used to conduct queries against DNS nameservers and is only available for Linux, Unix and OS X systems by default

Question 599

what is the ARP command used for ?

Answer 599

ARP command is used to display and modify entries in the address resolution protocol cache on a system.

Question 600

what is the command for viewing the ARP cache ?

Answer 600

arp -a

Question 601

what is the route command used for ?

Answer 601

route is used to view and manipulate the IP routing table in a windows osx or linux system

Question 602

what is a default route ?

Answer 602

route that takes effect when no other route is available for an IP destination address

Question 603

how would we print a routing table on a windows machine ?

Answer 603

route print

Question 604

what is the nbtstat command used for ?

Answer 604

used to view the current connection and statistics for devices communicating using the NetBIOS over TCP/IP protocol

Question 605

what is the netstat command used for ?

Answer 605

displays information for IP based connections on a client including its current sessions its source and destination IP’s and port numbers.

Question 606

what is the tcpdump command used for on linux systems?

Answer 606

Tcpdump – allows for the display of TCP/IP and other packets being transmitted or received over the network to the clients screen

Question 607

what is a network platform ?

Answer 607

1. routers
2. switches
3. firewalls

refers to any of these above items regardless of the brand or manufacturer

Question 608

what does the show interface command do ?

Answer 608

displays statistics for the network interfaces on the device

Question 609

what does the show config command do ?

Answer 609

show config - displays the current system configuration on the screen

Question 610

what is VTP?

Answer 610

VLAN trunking protocol

multiple VLANS in a single link

Question 611

what is a collision in regards to networking ?

Answer 611

occurs when two hosts on the network transmit at the same time which causes the signals to combine on the network medium

Question 612

where do collisions occur in networks ?

Answer 612

collisions can occur in both wired and wireless networks

Question 613

what is a collision domain ?

Answer 613

network segment where simultaneous data transmissions collide with each other

Question 614

how do we break apart collision domains ?

Answer 614

Use any layer 2 device to break apart collision domains like a switch or a bridge

Question 615

how can we as a network admin overcome and excessive collision issue ?

Answer 615

1. turn off auto negotiation
2. hardcode to lower speed
3. change to half duplex.

Question 616

what is a broadcast storm ?

Answer 616

occurs when a network system is overwhelmed by continuous or multicast or broadcast traffic

A broadcast storm or broadcast radiation is the accumulation of broadcast and multicast traffic on a computer network. Extreme amounts of broadcast traffic constitute a “broadcast storm”. It can consume sufficient network resources so as to render the network unable to transport normal traffic.

Question 617

what is a broadcast domain ?

Answer 617

a logical division of a computer network where all nodes can reach each other by broadcast at the data link layer

Question 618

what networking device can we use to break subnets into separate broadcast domains ?

Answer 618

we can use a router

Question 619

what are the couple main causes for a broadcast storm occurring in your network ?

Answer 619

1. too large singular broadcast domain
2. large volume of DHCP requests
3. loops are created in the switching environment

Question 620

what are the three main ways we can prevent broadcast storms from happening ?

Answer 620

1. enable bridge protocol data units
2. enforce a maximum number of MAC address’s per port
3. break up large broadcast domains using routers and layer 3 switches

Question 621

Duplicate Addresses: Logical domain manager ?

Answer 621

listens to multicast messages on a network and keeps track of the MAC addresses being used

Question 622

what will port security help us with in our network ?

Answer 622

to prevent issues on your network relating to duplicate MAC addresses you can enable port security on your switches.

Question 623

what is a duplicate IP address or Ip address conflict

Answer 623

occurs when another computer on the same network has an identical IP to another workstation or server on the same network (This can also be a DHCP server issue)

Question 624

how does duplicate IP addressing usually happen?

Answer 624

Duplicate IP addressing issues usually come from using static IP address’s

Question 625

what are the three main causes for duplicate IP addresses in a network ?

Answer 625

Static IP address issue

DHCP server issue

Rogue DHCP server

Question 626

Routing issues: multicast flooding

Answer 626

no specific host is associated with the multicast MAC address in the CAM table of the switch.

To fix this issue we need to disable multicast traffic on the switchport

Question 627

What is asymmetrical routing ?

Answer 627

Network packets leave via one path and return via a different path

Question 628

Routing issues: missing routes ?

Answer 628

when a router cannot reach a destination because there is a missing route in the routing table

Question 629

Loops: Switching / Bridging loops

Answer 629

occurs whenever there is more than one path between the source and the destination devices.

Question 630

How do we prevent a switching loop?

Answer 630

to prevent a switching loop you have to enable STP or spanning tree protocol

Question 631

what is the bottom line with switching loops ?

Answer 631

switching loops are usually an issue with how stp is configured

Question 632

what are routing loops ?

Answer 632

formed when an error occurs in the operation of the routing algorithm and creates a circular route amongst a group of network devices

Question 633

what are two ways to prevent routing loops in our network ?

Answer 633

split horizon
route poisoning

Question 634

Routing: What is split horizon ?

Answer 634

routing configuration that stops a route from being advertised back in the direction where it came from.

In computer networking, split-horizon route advertisement is a method of preventing routing loops in distance-vector routing protocols by prohibiting a router from advertising a route back onto the interface from which it was learned

Question 635

Routing: Route poisoning ?

Answer 635

increasing a routers metric to an infinitely high number after detecting one of its connected routes has failed

Route poisoning is a method of quickly forgetting outdated routing information from other router’s routing tables by changing its hop count to be unreachable (higher than the maximum number of hops allowed) and sending a routing update.

Question 636

Routing: hold down timer ?

Answer 636

prevents bad routes from being restored and passed to other routers by accident

Question 637

what does DHCP do when a client joins the network ?

Answer 637

automatically assigns an IP address, subnet mask, default gateway and DNS servers IP address to a client when it joins the network

Question 638

Rogue DHCP server ?

Answer 638

a DHCP server on a network which is not under the administrative control of the network admins

Question 639

what are the three ways rogue DHCP servers can be prevented

Answer 639

1. DHCP snooping
2. Port Security
3. Intrusion Detection system

Question 640

What is DHCP scope exhaustion ?

Answer 640

Occurs when the DHCP server runs out of Valid IPs to assign to the clients requesting access on the network

Question 641

what 4 pieces of information do clients need to communicate reliably on a network ?

Answer 641

1. IP address
2. Subnet Mask
3. Default Gateway IP
4. DNS Server IP

Question 642

What is a host based firewall ?

Answer 642

runs on an individual computer or device connected to the network to protect that one device

Question 643

what is a network based firewall ?

Answer 643

Deployed in line with the network traffic flow to monitor and filter incoming and outgoing network traffic based on established rule sets.

Question 644

firewall issues are commonly broken down into three main things

Answer 644

Access to protected resources from unprotected networks is not working

Access to unprotected resources from protected networks is not working

Access to the firewall and its configurations is not working

Question 645

firewall issues are one of two things.

Answer 645

Issues can usually be broken down into “either traffic is not going through the firewall or not going to the firewall properly “

Question 646

ACL?

Answer 646

provides security by blocking unauthorized users and allowing authorized users to access specific resources

Question 647

What command would we use to view firewall rules on a network based firewall

Answer 647

show access lists

Question 648

What are the 4 things to keep in mind when writing an ACL?

Answer 648

When writing an ACL rule keep these things in mind

Ensure there are no typos in your rules

Verify the protocol and port numbers referenced by the rule are correct

Verify the source and destination addresses are referenced by the rule

Did you include the correct IP and subnet mask

Verify the order of rules is being verified correctly

Question 649

what are two common questions to ask yourself when troubleshooting DNS?

Answer 649

Are the A records and CNAME records properly created ?

We can verify this using NSlookup

Is the TTL or time to live set properly

Question 650

What is DNS latency ?

Answer 650

time and delay that occurs whenever users request a particular domain name

Question 651

How do we solve DNS latency issues as a network admin ?

Answer 651

by using DNS servers that are closer to our users

Question 652

What do issues with NTP usually boil down too ?

Answer 652

NTP packets not being received

NTP packets not being processed

NTP packets have errors or packet lost

Question 653

How do we usually solve NTP issues ?

Answer 653

Ensure proper connection between clients and servers

Verify communication between clients and servers using MAC address

Verify communication between clients and servers using the IP addresses

Question 654

what is bandwidth ?

Answer 654

theoretical speed of data going across the network

Question 655

what is throughput ?

Answer 655

actual speed of data on the network

Question 656

wireless Received Signal Strength Indication RSSI ?

Answer 656

estimated measure of the power level that a radio frequency client device is receiving from a wireless access point or wireless router (otherwise known as signal strength)

Question 657

Wireless: Vertical antenna ?

Answer 657

radio frequency waves extend outward in all directions away from the antenna and the wireless access point to an equal power level

Question 658

Wireless: Dipole Antenna ?

Answer 658

produces radio frequency waves extending outward in two directions

Question 659

Wireless: Yagi Antenna ?

Answer 659

a unidirectional antenna that sends the radio frequency waves in only one direction

(commonly used for site to site connections)

Question 660

Wireless Parabolic Grid Antenna ?

Answer 660

allows the radio waves to be transmitted in only one direction over a longer distance then a yagi

Question 661

Wireless: what antennas are we more likely to use for indoor use ?

Answer 661

For indoor use you are more likely to use omnidirectional and unidirectional antennas

Question 662

Wireless: Channel Utilization?

Answer 662

a statistic or measure of the amount of airtime utilization that occurs for a particular frequency or channel

Question 663

where should our channel utilization be in our network to have a fast wireless network ?

Answer 663

In order to have a fast wireless network you want to keep your channel utilization under 30% to have a faster wireless network

Question 664

What do access points and clients form when they operate on the same channel ?

Answer 664

Access points and clients form a single broadcast domain when they operate on the same channel

Question 665

What is Clear Channel Assessment or CCA ?

Answer 665

listens to see if another device is actively transmitting on the channel before attempting to send frames on the channel

Question 666

When a wireless client attempts to connect to a wireless network it goes through a 7 step process

Answer 666

Wireless client sends a probe request to discover any 802.11 wireless networks in proximity to itself (broadcast message)

Receiving access point checks to see if it can support the data rate the client requested

Wireless client sends a low-level 802.11 authentication frame to the access point to begin authentication

Access point receives the authentication frame and responds with an acknowledgment to continue the handshake

Wireless client chooses the access point it wants to associate with and sends an association request

Access point processes the association request if the information sent matches its capabilities

Client is fully connected and associated and can now conduct any data transfer it needs and use the wireless network

Question 667

When a wireless client is connecting to the AP and the network it has to do the following

Answer 667

Scan airwaves

Find access points

Request association

Authenticate

Contact the DHCP server

Question 668

wireless: Coverage ?

Answer 668

a measure of how much area around a wireless transmitter is there sufficient signal strength for wireless devices to utilize

Question 669

What are a couple ways we can increase coverage to a wireless area ?

Answer 669

Signal booster

Larger antenna

Wireless repeater

Second access point

Question 670

Wireless: interference ?

Answer 670

occurs when multiple wireless networks communicate on the same channel using the same frequency

Question 671

Wireless: multipath reception ?

Answer 671

occurs when the transmitted signal bounces off walls and other phsical objects and then is redirected to the reciever

Question 672

Wireless: What are the ways a client can be disconnected from an Access point.

Answer 672

1. Idle timeout
2. Session timeout
3. Manual deletion
4. Wireless network change
5. Authentication timeout
6. Access point radio reset

Question 673

Captive portals ?

Answer 673

Captive portals usually rely on 802.1x, and 802.1x uses RADIUS for authentication. The IEEE 802.1x standard is a network authentication protocol that opens ports for network access when an organization authenticates a user’s identity and authorizes them for access to the network. This defines port security. The user’s identity is determined based on their credentials or certificate, which is confirmed by the RADIUS server.

Question 674

explain what the physical layer is in our networks

Answer 674

where transmission of bits across the network occurs

data is transferred in bytes at this layer series of 1s and 0s

Question 675

explain network availability

Answer 675

measure of how well a computer network can respond to connectivity and performance demands that are placed on it

Question 676

what does availability mean in our networks ?

Answer 676

being up and operational

Question 677

what does reliability mean in our networks ?

Answer 677

not dropping packets

Question 678

what is Mean time to repair MTTR ?

Answer 678

measures average time it takes to repair a network device when it breaks

Question 679

Mean time between failures MTBF?

Answer 679

measures average time between when failures occur on a device

Question 680

How can redundancy be achieved ?

Answer 680

redundancy is achieved using a single device or multiple devices

Question 681

explain network interface card teaming

Answer 681

using a group of network interface cards for load balancing and failover on a server or other device

Question 682

Hot standby router protocol HSRP?

Answer 682

Cisco’s proprietary first hop redundancy protocol which allows for an active and a standby router to be used together

Question 683

Virtual router redundancy protocol VRRP?

Answer 683

IETF’s open standard variant of HSRP which allows for an active router and multiple standby routers

Question 684

Gateway load balancing protocol GLBP?

Answer 684

Cisco’s proprietary first-hop redundancy which focuses on load balancing over redundancy

Cisco protocol

Question 685

Link Aggregation control Protocol LACP

Answer 685

achieves redundancy by having multiple links between the network devices where load balancers over multiple links can occur

Question 686

what do we need to keep in mind when designing redundant networks ?

Answer 686

Examine technical and operational goals

What is the function of this network

What are you trying to accomplish with this network

Identify the budget to fund high availability features

This can get really expensive

Categorize business applications into profiles

Establish performance standards for high availability solutions

Define how to manage and measure the high availability solutions

Question 687

what are the 4 options when we talk about recovery sites ?

Answer 687

Cold site

Warm site

Hot site

Cloud site

Question 688

Cold site

Answer 688

an available building that does not have any hardware or software in place or configure

Recovery with a cold site is going to be slow and time consuming

Question 689

Warm site

Answer 689

an available building that already contains a lot of the equipment

Recovery is going to be fairly quick

Question 690

Hot site

Answer 690

an available building that already has the equipment and data in place and configured

Very minimal downtime but this is very expensive

Question 691

Cloud site

Answer 691

allows for the creation of a recovery version of an organizations enterprise network in the cloud

Question 692

Recovery time objective ?

Answer 692

duration of time and service level within which a business process must be restored after a disaster to avoid unacceptable consequences

Question 693

Explain a full backup ?

Answer 693

complete backup of every single file on a machine

Question 694

incremental backup ?

Answer 694

only backs up data that changed since the last backup

Question 695

Differential backup

Answer 695

only backs up the data since the last full backup

Question 696

Uninterruptible Power Supply UPS?

Answer 696

provides emergency power to a load when the input power source or main power fails

Question 697

Power Distribution Unit PDU

Answer 697

Distributes electric power to racks of computers and network equipment located within a data center

Question 698

what are the three main types of WAN connections in a business ?

Answer 698

1. dedicated lease lines
2. circuit switched
3. packet switched connections

Question 699

WAN: dedicated lease line ?

Answer 699

logical connection that connects two sites through a service providers facility or a telephone

Question 700

how would you describe a dedicated leased line?

Answer 700

a dedicated lease line is a single pipe going from your service providers office to your business office

Question 701

WAN: circuit switched connection ?

Answer 701

connection is brought up only when needed similiar to making a phone call.

essentially this is full access when you need it but when you dont need it its not there

Question 702

WAN: packet switched connection ?

Answer 702

works like an always-on dedicated lease line but multiple customers share the same bandwidth

Question 703

what are the options for wireless wan connections ?

Answer 703

1. cellular
2. microwave
3. satelite
4. high-frequency radio

Question 704

what are the three technoogies we may find when dealing with 3G

Answer 704

1. WCDMA
2. HSPA
3. HSPA +

Question 705

WAN: wideband code division multiple access or WCDMA?

Answer 705

used by the UTMS standard and could reach data speeds of up to 2 MBPS

Question 706

WAN: high speed packet access HSPA?

Answer 706

reaches speeds of up to 14.4 mbps and is sometimes referred to as 3.5 G

Question 707

WAN: High speed packet access evolution HSPA+?

Answer 707

reaches speeds of up to 50 MBPS and is sometimes reffered to as 3.75 G

Question 708

what are the three differentbands 5G comes with ?

Answer 708

low-band, mid-band, high-band as you go up in the bands you get higher speeds but less coverage

Question 709

GSM global system for mobile communication ?

Answer 709

a cellular tech that takes the voice during a call then converts it to digital data

Question 710

Code division multiple access ?

Answer 710

a cellular technology that uses code division to split up a channel

Question 711

microwave connection?

Answer 711

uses a beam of radio waves in the microwave requency range to transmit info between two fixxed locations

Question 712

statelite connection ?

Answer 712

a method osusing communication satelites located in space to connect a user to the internet

Question 713

Channel service unit data service unit or CSU/DSU?

Answer 713

terminates the digital signals at the customers location

Question 714

EXAM: what are T1s and D1s ?

Answer 714

these are dedicated leased lines

Question 715

what is the speed of a T1 connection ?

Answer 715

T1 has a speed of 1.544 mbps

Question 716

what is the speed of a T3 connection ?

Answer 716

T3 has a speed of 44.7 MBPS

Question 717

what is the speed of an E1 connection ?

Answer 717

E1 has a speed of 2.0 mbps

Question 718

what is metro ethernet?

Answer 718

less expensive and more common than specialized serial ports used in a CSU/DSU environment

service provider gives you an ethernet jack that you can plug into your router

An increasingly popular leased line is one called Metro Ethernet. This is ethernet that you would connect in a regional area or a city area and be able to simply have ethernet at both ends of the connection. We would normally use a T1, or E1, or some other type of WAN. So this is not something that you commonly see, but you can obviously see the advantages. All of your equipment already has ethernet on it, so why not simply plug-in and not use any additional equipment just to connect sites together.

Question 719

point-to-poit PPP connection ?

Answer 719

commonly used layer 2 protocol on dedicated lease lines to transmit multiple layer 3 protocols such as IP and IPX

Question 720

what cann PPP connections use for authentication ?

Answer 720

PAP
CHAP

Question 721

PAP or passsword authentication protocol ?

Answer 721

performs one-way authentication between a client and a server

Question 722

How does the Challenge-handshake authentication protocol or CHAP perform authentication?

Answer 722

performs one way auth using a three-way handshake

Question 723

how secure are PAP credentials ?

Answer 723

they are not secure at all because they are sent in the clear

Question 724

how secure are credentials when using the CHAP authentication methods ?

Answer 724

chap uses hashed credentials which are way more secure then PAP

Question 725

Point-to-point over ethernet or PPPOE?

Answer 725

a network protocol for encapsulation point-to-point protocol frames inside ethernet frames

Question 726

explain cable modems ?

Answer 726

uses a cable television infastructure that is made up of hybrid fiber-coax distribution network

Question 727

what are HFC and doxis associated with ?

Answer 727

cable modems

Question 728

how do cable modems transmit and recieve data ?

Answer 728

cable modems transmit and recieve over cable television infastructure

Question 729

Where are satelite modems used and what are the potential drawbacks ?

Answer 729

used in remote, rural, or disconnected locations where other connections are not available

weather can weaken signals

satelite usually has higher latency because of the distance it has to travel

Question 730

Plain old telephone service or POTS?

Answer 730

runs on public switchedtelephone network PTSN which consists of all telephone carriers from around the world

Question 731

Integrated Services Digital Network ISDN?

Answer 731

an older technology designed to carry voice, video, or data over B bearer channels / puts and bind channels together

Question 732

Frame relay?

Answer 732

creates virtual circuits to connect remote LANs to WANs

Wan technology

was a departure from circuit switched T1s

with frame relay lan traffic is encapsulated into frame relay frames

Frame relay was replaced with MPLS

MPLS is the defualt for WAN’s nowadays

Question 733

SONET

Answer 733

layer 1 tech that uses fiber as its media and has high data rates which range from 155 mbps to 10 gbps or more

multiplex digital signals over optical cable

Question 734

what does ATM deal with ?

Answer 734

ATM deals with Fiber and SONET networks

Question 735

Multiprotocol label switching MPLS?

Answer 735

allows traffic to be dynamically routed based on load conditions and path availability / this is primarily used by service providers on there backbone networks

Question 736

Dynamic multiport virtual private network DMVPN?

Answer 736

allows internet to be used as WAN connection for secure site-to-site communication

• allows remote sites to build the VPN between each other and tear it down
• cisco protocol

Question 737

Software-defined wide area network SD-WAN ?

Answer 737

allows for leveraging any combo of transport services to securely connect users to their applications / essentially a software based WAN architecture

Question 738

Multipoint generic routing encapsulation MGRE?

Answer 738

Enables one node to communicate with many other nodes essentially creating a point-to-multipoint link

MGRE is often used in DMVPN

Question 739

what can you use MGRE for ?

Answer 739

You can use MGRE at your main office to connect branch offices back to it

Question 740

what is MGRE usually combined with ?

Answer 740

MGRE is usually going to be combined with DMVPN

MGRE is used to create tunnels from one node to multiple nodes

Question 741

what is bandwidth ?

Answer 741

theoretical speed of data going across the network

Question 742

throughput ?

Answer 742

actual speed of data on the network

Question 743

Received Signal Strength Indication RSSI ?

Answer 743

estimated measure of the power level that a radio frequency client device is receiving from a wireless access point or wireless router (otherwise known as signal strength)

Question 744

Effective Equivalent Isotropic Radiated Power EIRP?

Answer 744

maximum power radiated from an ideal isotropic antenna, given its antenna gain, and the transmitter power of the radio frequency system

Question 745

what is an omnidirectional antenna considered ?

Answer 745

An omnidirectional antenna is considered Isotropix

Question 746

what are most wireless AP’s going to use?

Answer 746

Most wireless access points are going to use omni directional antennas

Question 747

Vertical antenna?

Answer 747

radio frequency waves extend outward in all directions away from the antenna and the wireless access point to an equal power level

Question 748

Dipole antenna?

Answer 748

produces radio frequency waves extending outward in two directions

Question 749

Yagi antenna?

Answer 749

a unidirectional antenna that sends the radio frequency waves in only one direction
(commonly used for site to site connections)

Question 750

Parabolic grid antenna?

Answer 750

allows the radio waves to be transmitted in only one direction over a longer distance than a yagi antenna (commonly used for site to site connections)

Question 751

what antennas are we most likely to use inside ?

Answer 751

For indoor use you are more likely to use omnidirectional and unidirectional antennas

Question 752

Polarization?

Answer 752

the orientation of the electric field or transmission from the Antenna

Question 753

do most wifi networks use vertical or horiziontal ?

Answer 753

Most Wi-Fi networks use vertical polarization

Question 754

Channel Utilization?

Answer 754

a statistic or measure of the amount of airtime utilization that occurs for a particular frequency or channel

Question 755

what should our channel utilization be at to have a fast wireless network ?

Answer 755

In order to have a fast wireless network you want to keep your channel utilization under 30% to have a faster wireless network

Question 756

Access points and clients form a single broadcast domain when they operate on the same channel

Answer 756

expand on this

Question 757

Clear Channel Assessment CCA?

Answer 757

listens to see if another device is actively transmitting on the channel before attempting to send frames on the channel

Question 758

Site survey?

Answer 758

process of planning and designing a wireless network to provide the required wireless solution

Question 759

When a wireless client attempts to connect to a wireless network it goes through a 7 step process

Answer 759

1. Wireless client sends a probe request to discover any 802.11 wireless networks in proximity to itself (broadcast message)
   
   2. Receiving access point checks to see if it can support the data rate the client requested
   3. Wireless client sends a low-level 802.11 authentication frame to the access point to begin authentication
   4. Access point receives the authentication frame and responds with an acknowledgment to continue the handshake
   5. Wireless client chooses the access point it wants to associate with and sends an association request
   6. Access point processes the association request if the information sent matches its capabilities
      Client is fully connected and associated and can now conduct any data transfer it needs and use the wireless network

Question 760

When a wireless client is connecting to the AP and the network it has to do the following ?

Answer 760

Scan airwaves
Find access points
Request association
Authenticate
Contact the DHCP server

Question 761

Coverage?

Answer 761

a measure of how much area around a wireless transmitter there is sufficient signal strength for wireless devices to utilize

Question 762

how do we determine coverage with wireless networks ?

Answer 762

by conducting a wireless site survey

Question 763

how do we increase coverage to a wireless area ?

Answer 763

Signal booster
Larger antenna
Wireless repeater
Second access point

Question 764

Interference?

Answer 764

occurs when multiple wireless networks communicate on the same channel using the same frequency

Question 765

Attenuation?

Answer 765

reduction of signal strength between the transmission and receipt of the signal

Question 766

Multipath reception?

Answer 766

occurs when the transmitted signal bounces off walls and other physical objects and then is redirected to the receiver

Question 767

There are lots of reasons a client can be disassociated from an access point these include

Answer 767

Idle timeout
Session timeout
Manual deletion
Wireless network change
Authentication timeout
Access point radio reset

Question 768

Service set Identifier SSID?

Answer 768

a natural language name used to identify a wireless network in an 802.11 network

Question 769

Captive portals?

Answer 769

a web page displayed to newly-connected WI-FI users before being granted broader access to network resources

Question 770

Captive portal: HTTP redirect?

Answer 770

redirects all traffic to a web server which then redirects them to a captive portal using a 302 HTTP status code

Question 771

Captive portal: Icmp redirect?

Answer 771

sends error messages and operational information indicating the success or failure of communicating with another IP address

Question 772

Captive portal: DNS redirect?

Answer 772

the client is redirected by the onboard DNS server to the captive portal webpage

Question 773

Captive portals and radius ?

Answer 773

Captive portals usually rely on 802.1x, and 802.1x uses RADIUS for authentication. The IEEE 802.1x standard is a network authentication protocol that opens ports for network access when an organization authenticates a user’s identity and authorizes them for access to the network. This defines port security. The user’s identity is determined based on their credentials or certificate, which is confirmed by the RADIUS server.

Question 774

what is Network availability?

Answer 774

measure of how well a computer network can respond to connectivity and performance demands that are placed upon it

Question 775

Availability?

Answer 775

being up and operational

Question 776

Reliability?

Answer 776

not dropping packets

Question 777

Mean time to repair MTTR?

Answer 777

measures average time it takes to repair a network device when it breaks / want this to be a very small number

Question 778

Mean Time Between Failures MTBF?

Answer 778

measures average time between when failures occur on a device / want this to be a very large number

Question 779

how is redundancy achieved ?

Answer 779

Redundancy is achieved using a single device or multiple devices

Question 780

Network interface card teaming ?

Answer 780

using a group of network interface cards for load balancing and failover on a server or other device

Question 781

Layer 3 redundancy?

Answer 781

used if the default gateway goes down and clients couldn’t leave the subnet

Question 782

Hot standby router protocol HSRP?

Answer 782

cisco’s proprietary first-hop redundancy protocol which allows for an active and a standby router to be used together

Question 783

Virtual Router Redundancy protocol VRRP?

Answer 783

IETF’s open standard variant of HSRP which allows for an active router and multiple standby routers

Question 784

Gateway load balancing protocol GLBP?

Answer 784

Cisco’s proprietary first-hop redundancy which focuses on load balancing over redundancy

Question 785

Link Aggregation control Protocol LACP?

Answer 785

allows the user to combine numerous physical Ethernet links into one logical link, which helps create load balancing in the interfaces.

Question 786

When looking at designing redundant networks keep in mind the following ?

Answer 786

1. Examine technical and operational goals
   a. What is the function of this network
   b. What are you trying to accomplish with this network
2. Identify the budget to fund high availability features
   a. This can get really expensive
3. Categorize business applications into profiles
4. Establish performance standards for high availability solutions
   Define how to manage and measure the high availability solutions

Question 787

There are really 4 options when we talk about recovery sites

Answer 787

Cold site
Warm site
Hot site
Cloud site

Question 788

Cold site?

Answer 788

an available building that does not have any hardware or software in place or configure
Recovery with a cold site is going to be slow and time consuming

Question 789

Warm site?

Answer 789

an available building that already contains a lot of the equipment
Recovery is going to be fairly quick

Question 790

Hot site?

Answer 790

an available building that already has the equipment and data in place and configured
Very minimal downtime but this is very expensive

Question 791

Cloud site?

Answer 791

allows for the creation of a recovery version of an organizations enterprise network in the cloud

Question 792

Recovery time objective or RTO ?

Answer 792

duration of time and service level within which a business process must be restored after a disaster to avoid unacceptable consequences

Question 793

what question does RTO answer for us ?

Answer 793

RTO answers the question of how much time did it take to recover after the notification of a business process disruption

Question 794

what should we use for low RTO situations ?

Answer 794

Use either a hot site or a cloud site for low RTO situations

Question 795

Recovery point Objective RPO?

Answer 795

interval of time during a disruption before data lost exceeds the Business Continuity plan maximum allowable threshold or tolerance

Question 796

Different backups ?

Answer 796

Full backup – complete backup of every single file on a machine

Incremental backup – only backs up data that changed since the last backup

Differential backup – only backs up the data since the last full backup

Snapshot – read only copy of your data from a point in time

Question 797

Uninterruptible Power Supply UPS?

Answer 797

provides emergency power to a load when the input power source or main power fails

Question 798

Power Distribution Unit PDU?

Answer 798

Distributes electric power especially to racks of computers and network equipment located within a data center

Question 799

How do we provide power to our servers during a blackout ?

Answer 799

Generally a PDU is combined with a UPS or generator to provide power during a blackout

Question 800

Wet pipe system?

Answer 800

using a sprinkler system and pipes that always contain water – a leak in the pipe could be very dangerous we should not use this

Question 801

Quality of service QOS

Answer 801

enables strategic optimization of network performance based on different types of traffic

Question 802

There are different categories of QOS what are the three big ones we need to be aware of?

Answer 802

Delay

Jitter

Drops

Question 803

QOS: Delay?

Answer 803

the time a packet travels from the source to the destination – measured in miliseconds – this is a big deal with voice or streaming video

Question 804

QOS:` Jitter ?

Answer 804

uneven arrival of packets which is especially harmful in VOIP traffic

Question 805

QOS: Drops?

Answer 805

occurs during link congestion when a routers interface queue overflows and cause packet loss

Question 806

Effective bandwidth?

Answer 806

is going to be the lowest bandwidth of the device in the network stream

Question 807

what is the purpose of QOS?

Answer 807

to categorize traffic, apply a policy, and prioritize traffic in accordance with a Qos Policy

a family of evolving Internet standards that provides ways to give preferential treatment to certain types of IP traffic

Question 808

QOS: what are the three different mechanisms you can use when categorizing your traffic ?

Answer 808

best effort

No QOS traffic is first in and first out

Integrated services Hard QOS

Traffic has strict bandwidth reservations

Differentiated services Soft QOS

Has differentiation of data types where routers and switches can make decisions based on markings and fluctuate traffic

Question 809

how do we classify traffic with QOS ?

Answer 809

Classification

Traffic is placed into different categories

Marking

Alters bits within a frame, cell, or packet which indicates handling of traffic

Congestion Management

Determines the order in which packets are sent out an interface based on priorities assigned to those packets

Congestion avoidance

Newly avoided packets would be discarded if the devices output queue fills to capacity

Policing and shaping

Policing – typically discards packets exceeding the configured rate limit

Shaping - Allows buffer to delay traffic from exceeding the configured rate

Link efficiency

Packet payload is compressed to conserve bandwidth

VOIP payload can be reduced by 50%

Question 810

are there collosions with full duplex mode ?

Answer 810

no collosions cannot happen in full duplex mode

Question 811

loopback plug ?

Answer 811

useful for testing physical ports

sends traffic out one port and right back into the port

Question 812

how does a network device determine if a specific packet is the start of a new traffic flow ?

Answer 812

tcp flags

Question 813

SD-WAN?

Answer 813

software defined networking in a wide area network

a WAN built for the cloud

Question 814

LAG and mirrioring ?

Answer 814

port bonding / link aggregation

multiple interfaces acts like one big interface

Question 815

LACP ?

Answer 815

link aggregaton control protocol

you can combine 4 10 GB ports to equal 40GB ports

Question 816

what is the network layer sometimes referred to as ?

Answer 816

the routing layer!

IP addresses operate at the network layer

Question 817

what is the maximum supported distance of a 1000 base-T copper cable

Answer 817

100 meters

Question 818

what are the three main types of copper media ?

Answer 818

coaxial
twisted pair
serial

Question 819

what is an RG-6 cable typicaly used for ?

Answer 819

RG-6 is commonly used by ISP’s to connect internet to your home

Question 820

what are the two main connector used when it comes to coaxial cables ?

Answer 820

F-type
BNC

Question 821

what is an f-type connector ?

Answer 821

commonly used in cable tv
this is a skrew in type of connection

Question 822

what is a BNC connector

Answer 822

this is a push in connector used with coaxial cable

Question 823

what are twinaxial cable used for ?

Answer 823

twinaxial cables are used for very short range high speed connections between devices

Question 824

what is the most commonly used LAN cable ?

Answer 824

twisted pair

you use these at work all the time its on every desk at flagship

Question 825

what is the best range for UTP and STP to operate ?

Answer 825

0-100 meters

Question 826

what are the two connector types used with twisted pair cabeling ?

Answer 826

RJ45
RJ11

Question 827

what are RJ45 connectors typically used for ?

Answer 827

commonly used for data transfer

Question 828

what is the standard for trunking ?

Answer 828

802.1q

Question 829

Compare and contrast ethernet standards and there maximum supported distance.

Answer 829

1000base-T 100 meters
10Gbase-T 100 meters
40G base-t - 30 meters

Question 830

what protocols are used for incoming mail communication ?

Answer 830

IMAP and POP3 are used for incoming mail communication

Question 831

what is required to get data from one side of the network to the other ?

Answer 831

1. Server IP address
2. protocol = TCP/UDP
3. Server application port number
4. client IP address
5. protocol
6. client port number

Question 832

Unicast ?

Answer 832

one station sending information to another station

web surfing and file transfers are unicast traffic

Question 833

PDU protocol data unit?

Answer 833

a protocol data unit is a unit of transmission

the PDU’s are different groups of Data at different OSI layers

Ethernet operates on a frame of data

the TCP PDU is a segment
the UDP PDU is a datagram

Question 834

RSTP rapid spanning tree protocol

Answer 834

802.1W

RSTP has a faster convergence this took the convergence time from 30 to 50 seconds to 6

you can use both STP and RSTP in a network and they can coexist

Question 835

What are the common Interior Gateway protocols ?

Answer 835

OSPF
RIP
EIGRP

Question 836

what version of OSPF would we use for IPV6

Answer 836

OSPF v3

Question 837

how long is an IPV6 address in bytes ?

Answer 837

128 bits long

Question 838

what are the private IP address ranges ?

Answer 838

10.0.0.0-10.255.255.255
172.16.0.0-172.31.255.255
192.168.0.0-192.168.255.255

Question 839

where are jumbo frames commonly used ?

Answer 839

in a SAN network environment

Question 840

What are ACL’s used for in our networks ?

Answer 840

ACL’s are used to deny or allow traffic

Question 841

what protocl is EAP a part of ?

Answer 841

802.1x