General Questions Part 1 Flashcards

1
Q

FCS

A

Frame Check Sequence (FCS) is an error-detecting code added to a frame in a communications protocol to determine if the frame arrived intact.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Preamble

A

The preamble functions like the outriders in a presidential motorcade. They tell everyone ahead to wake up and pay attention: something important is coming. Apart from being a “get ready” notification, the preamble also serves as a clock synchronization device.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Full Duplex

A

Send and receive data simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Half Duplex

A

Cannot send and receive data simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

CSMA/CD

A

Short for carrier sense multiple access/collision detection. Before a node transmits data, it checks or listens to the network. When the network is not busy, the node sends its data. If it detects traffic, it will wait a random amount of time and try again. Collision Detection (CD) will happen if two or more nodes send data down the wire and they collide, the nodes will be notified and wait a random amount of time and try again. No longer an issue on modern networks, happened on older Ethernet networks with hubs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Carrier Sense

A

Can detect what is going on over the transmission medium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Multiple Access

A

Every node on the network has equal rights to access and use the shared medium, but they must take turns.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Collision Detection

A

If two or more nodes send data down the wire and they collide, the nodes will be notified and wait a random amount of time and try again.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Broadcast Domain

A

A broadcast domain is a logical division of a computer network in which all nodes can reach each other by broadcast at the data link layer. A broadcast domain can be within the same LAN segment or it can be bridged to other LAN segments. Separated by routers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Collision Domain

A

A collision domain is a network segment connected by a shared medium or through repeaters where simultaneous data transmissions collide with one another. Separated by switch/bridge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Unicast

A

One-to-one relationship, one station sending information to another single station.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Broadcast

A

One-to-many relationship, send from one station to all stations on a broadcast domain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Multicast

A

One-to-many relationship, send from one station to all interested stations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

LAN

A

Local Area Network - A group of devices in the same broadcast domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

VLAN

A

Virtual Local Area Network - A group of devices in the same broadcast domain, separated logically rather than physically.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

VLAN ID

A

Virtual Local Area Network Identification - 12 bits long, 4,094 VLANS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Trunking

A

Trunking is a technique used in data communications transmission systems to provide many users with access to a network by sharing multiple lines or frequencies. As the name implies, the system is like a tree with one trunk and many branches. Trunking is commonly used in very-high-frequency (VHF) radio and telecommunication systems.

Trunking can also be defined as a network that handles multiple signals simultaneously. The data transmitted through trunking can be audio, video, controlling signals or images.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Loop Protection

A
IEEE standard 802.1D to prevent loops
in bridged (switched) networks. Without loop protection, two switches connected to each other will send traffic back and forth forever.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

IEEE standard 802.1D

A

Prevents loops in switched networks, used practically everywhere.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the STP port states?

A

Blocking - Not forwarding to prevent a loop
Listening - Not forwarding and cleaning the MAC table
Learning - Not forwarding and adding to the MAC table
Forwarding - Data passes through and is fully operational
Disabled - Administrator has turned off the port

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

RSTP

A

Rapid Spanning Tree Protocol (IEEE 802.1w). Latest upgrade to STP, convergence from 30 to 50 seconds to 6 seconds. Backwards compatible with 802.1D STP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Routing Table

A

Data table stored in a router that lists the routes to a particular network destination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Static Routing

A

Add routes to a router manually, done by an admin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Dynamic Routing

A

Routes in a router are added automatically.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Default Route

A

When no route is listed in the routing table, use the route that’s defined as default.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Ephemeral Ports

A

Ports that temporary and not permanent, ports range from 1,024 - 65,535.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Ports

A

Permanent ports that are well-known, ports range from 0 - 1,023.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How many bits are IPv4 and IPv6 addresses?

A

IPv4 - 32 bits, 4 octets in decimal

IPv6 - 128 bits, addresses in hexadecimal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Dual-stack routing

A

Routing that allows both IPv4 and IPv6 to be used interchangeably, most modern networks have support for this. Each protocol has it’s own configuration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Teredo/Miredo

A

End-to-End tunneling which allows IPv6 through IPv4 networks that do not have dual-stack routing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Packet/Traffic Shaping

A

Used on computer networks to delay some or all datagrams to bring them into compliance with a desired traffic profile. Used to optimize or guarantee performance, improve latency, or increase usable bandwidth for some kinds of packets by delaying other kinds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

QoS

A

Quality of Service - Description or measurement of the overall performance of a service, such as a telephony or computer network or a cloud computing service, particularly the performance seen by the users of the network. To quantitatively measure quality of service, several related aspects of the network service are often considered, such as packet loss, bit rate, throughput, transmission delay, availability, jitter, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

NAT

A

Network Address Translation - Translates private network IP address into public IP addresses that can routed over the internet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Port Forwarding

A

Also called Destination NAT or Static NAT. Translates public port/IP addresses to private port/IP addresses to access internal services.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

ACL

A

Access Control List - Packet filter used to allow or deny traffic, can be configured for both incoming and outgoing traffic. Can filter based on criteria such as source IP, destination IP, TCP/UDP port.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Circuit Switching

A

A method of implementing a telecommunications network in which two network nodes establish a dedicated communications channel (circuit) through the network before the nodes may communicate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

POTS

A

Plain Old Telephone Service

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

PSTN

A

Public Switched Telephone Service - The world’s collection of interconnected voice-oriented public telephone networks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

ISDN

A

Integrated Services Digital Network - A set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Packet Switching

A

A method of grouping data that is transmitted over a digital network into packets.

41
Q

SDN

A

Software-defined networking - an approach to network management that enables dynamic, programmatically efficient centrally managed network configuration in order to improve network performance and monitoring making it more like cloud computing than traditional network management.

42
Q

Distributed Switching

A

Distributed switching is a virtual network distributed across all physical platforms, there is no need for physical segmentation. Distributed switching allows similar services to live on the same VLAN, segmenting the network by logical services.

43
Q

Explain bit vs byte

A

Bit - a single digit, either a 0 or 1

Byte - Comprised of 8 bits, often call an octet

44
Q

Subnet Mask

A

A subnet mask separates the IP address into the network and host addresses, used by the local device to determine what network the device is on.

45
Q

Default Gateway

A

Router, allows you to communicate outside of your local subnet. The default gateway must be an IP address on the local subnet.

46
Q

Loopback Address

A

An address to yourself, used to test TCP/IP stack on local device, ping 127.0.0.1
Ranges from 127.0.0.1 to 127.255.255.254

47
Q

Reserved Address

A

Set aside for future use or testing.

Ranges from 240.0.0.1 to 255.255.255.254

48
Q

Virtual IP Address

A

Not associated with a physical network adapter, rather used by a virtual machine, internal router address

49
Q

Class A Address

A

IP address starts between 1 - 126. 8 bits for network, 24 bits for host.

50
Q

Class B Address

A

IP address starts between 128 - 191. 16 bits for network, 16 bits for host.

51
Q

Class C Address

A

IP address starts between 192 - 223. 24 bits for network, 8 bits for host.

52
Q

Network Address

A

The first IP address of a subnet, all host bits are set to 0.

ex: Given 172.16.88.200 (Class B)
Network Address 172.16.0.0

53
Q

First usable host address

A

The first IP address of a subnet that can be used by a host, all host bits are set to 0 then increase the last octet by 1.

ex: Given 172.16.88.200 (Class B)
First usable host address 172.16.0.1

54
Q

Last usable host address

A

The last IP address of a subnet that can be used by a host, all host bits are set to 1 then decrease the last octet by 1.

ex: Given 172.16.88.200 (Class B)
Last usable host address 172.16.255.254

55
Q

Network broadcast address

A

The last IP address of a subnet, all host bits are set to 1.

ex: Given 172.16.88.200 (Class B)
Network broadcast address 172.16.255.255

56
Q

How are IPv6 addresses assigned to ISPs?

A

The Internet Assigned Numbers Authority (IANA) provides address blocks to Regional Internet Registries (RIR). RIR assigns smaller subnet blocks to Internet Service Providers (ISP). ISP assigns a /48 subnet to the customer.

57
Q

VLSM

A

Variable-Length Subnet Masking (VLSM) amounts to “subnetting subnets,” which means that VLSM allows network engineers to divide an IP address space into a hierarchy of subnets of different sizes, making it possible to create subnets with very different host counts without wasting large numbers of addresses.

58
Q

DHCP

A

Dynamic Host Configuration Protocol - a network management protocol used on Internet Protocol networks whereby a DHCP server dynamically assigns an IP address and other network configuration parameters from a pool of predefined addresses to each device on a network so they can communicate with other IP devices and networks.

59
Q

APIPA

A

Automatic Private Internet Protocol Addressing - A link local IP address that cannot be forwarded through a router. IP range is from 169.254.1.0 to 169.254.255.254. An address between this range gets automatically assigned if DHCP is enabled on a device but unable to get a legitimate IP address. Uses ARP to confirm address isn’t in use when assigned an APIPA address.

60
Q

WLAN

A

Wireless Local Area Network - A group of wireless devices in the same broadcast domain. Uses 80.11

61
Q

MAN

A

Metropolitan Area Network - A network in your city, larger than a LAN.

62
Q

WAN

A

Wide Area Network - Spans states, countries, and even globally, generally connects LAN’s across a vast distance.

63
Q

CAN

A

Campus/Corporate Area Network - A network across a group of multiple buildings in the same area. Often buildings are connected via fiber cabling.

64
Q

NAS

A

Network Attached Storage - a file-level (as opposed to block-level) computer data storage server connected to a computer network providing data access to a group of clients. NAS is specialized for serving files either by its hardware, software, or configuration.

65
Q

SAN

A

Storage Area Network - a computer network which provides access to consolidated, block-level data storage. SANs are primarily used to enhance accessibility of storage devices, such as disk arrays and tape libraries, to servers so that the devices appear to the operating system as locally-attached devices.

66
Q

PAN

A

Personal Area Network - a computer network for interconnecting electronic devices centered on an individual person’s workspace.[1] A PAN provides data transmission among devices such as computers, smartphones, tablets and personal digital assistants.

67
Q

Z-Wave

A

A wireless communications protocol used primarily for home automation. It is a mesh network using low-energy radio waves to communicate from appliance to appliance, allowing for wireless control of residential appliances and other devices, such as lighting, security systems, thermostats, windows, locks, swimming pools, and garage door openers.

68
Q

Bluetooth

A

A wireless technology standard used for exchanging data between fixed and mobile devices over short distances using short-wavelength UHF radio waves in the industrial, scientific and medical (ISM) radio bands, from 2.402 GHz to 2.480 GHz, and building personal area networks (PANs).

69
Q

NFC

A

Near-Field Communication - A set of communication protocols for communication between two electronic devices over a distance of 4 cm or less. Typically used for payment systems and access tokens.

70
Q

ANT/ANT+

A

Adaptive Network Topology - A proprietary (but open access) multicast wireless sensor network technology designed and marketed by ANT Wireless (a division of Garmin Canada). It is primarily used for sports and fitness sensors.

71
Q

802.11

A

Managed by IEEE, often updated and has different standards.

72
Q

802.11a

A

5 GHz range, 54 Mbit/s , not common today

73
Q

802.11b

A

2.4 GHz range, 11 Mbit/s, further range than 802.11a, lots of devices operate at the 2.4GHz frequency so subject to interference.

74
Q

802.11g

A

2.4 GHz range, 54 Mbit/s, backwards compatible with 802.11b and is essentially an upgrade of 802.11b.

75
Q

802.11n

A

2.4 or 5 GHz range, 40 MHz channel width, 600 Mbit/s, uses MIMO

76
Q

802.11ac

A

5 GHz, 160 MHz channel width, 7Gbit/s, uses MIMO

77
Q

MIMO

A

Multiple-Input and Multiple-Output - A method for multiplying the capacity of a radio link using multiple transmission and receiving antennas to exploit multipath propagation.

78
Q

TDMA

A

Time-Division Multiple Access - is a channel access method for shared-medium networks. It allows several users to share the same frequency channel by dividing the signal into different time slots.[1] The users transmit in rapid succession, one after the other, each using its own time slot. This allows multiple stations to share the same transmission medium (e.g. radio frequency channel) while using only a part of its channel capacity.

79
Q

CDMA

A

Code-Division Multiple Access - is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel. This allows several users to share a band of frequencies.

80
Q

What is LTE when talking about 4G and LTE

A

Long Term Evolution - is a standard for wireless broadband communication for mobile devices and data terminals, based on the GSM/EDGE and UMTS/HSPA technologies. It increases the capacity and speed using a different radio interface together with core network improvements. Supports download rates of 150 Mbit/s.

81
Q

LTE Advanced (LTE-A)

A

Long Term Evolution Advanced- Supports download rates of 300 Mbit/s.

82
Q

Omnidirectional Antenna

A

Most common antenna, signal is evenly distributed on all sides

83
Q

Directional Antenna

A

Focuses the signal in a particular direction

84
Q

Wireless Survey Tools

A

Finds signal coverage and potential interference.

85
Q

SaaS

A

Software-as-a-Service - is a software licensing and delivery model in which software is licensed on a subscription basis and is centrally hosted. It is sometimes referred to as “on-demand software”. Ex. DropBox

86
Q

IaaS

A

Infrastructure-as-a-Service - Outsource your equipment but you’re still responsible for the management and security. Ex. AWS

87
Q

PaaS

A

Platform-as-a-Service - is a category of cloud computing services that provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app. Ex. Salesforce

88
Q

CASB

A

Cloud Access Security Broker is on-premises or cloud based software that sits between cloud service users and cloud applications, and monitors all activity and enforces security policies. A CASB can offer a variety of services such as monitoring user activity, warning administrators about potentially hazardous actions, enforcing security policy compliance, and automatically preventing malware.

89
Q

DNS

A

Translates human-readable names into computer readable IP addresses. Hierarchical, follows a path. There are 13 root DNS server clusters with hundreds of top level domains such as .com, .net, .org, .gov, etc.

90
Q

DNS Records

A

Resource Records - the database records of domain name services. Holds domain name and associated IP address in a text file. a DNS server has over 30 record types.

91
Q

Address Records (A) and (AAAA)

A

Defined the IP address of a host, (A) record type is used for IPv4 and (AAAA) is used for IPv6.

92
Q

Canonical Record

A

Is a type of resource record in the Domain Name System (DNS) which maps one domain name (an alias) to another (the canonical name).

93
Q

DHCP Pool

A

Grouping of IP addresses, each subnet has its own scope and a scope is generally a contiguous pool of IP addresses. DHCP exceptions can be made inside the scope.

94
Q

NTP

A

Network Time Protocol - Every devices has its own clock (every switch, router, firewall, server, workstation, etc.). These clocks automatically update with NTP servers and syncs device clock with server clock.

95
Q

UTP

A

Unshielded Twisted Pair

96
Q

STP

A

Shielded Twisted Pair

97
Q

Plenum Space

A

Part of a building that can facilitate air circulation for heating and air conditioning systems usually at greater than atmospheric pressure. Space between the structural ceiling and the dropped ceiling or under a raised floor is typically considered plenum.

98
Q

Plenum-rate Cable

A

Plenum-rated cable is not as flexible as traditional cable jackets as the jackets need to be fire-rated.

99
Q

Coaxial Cables

A

RG-6 - Used in television/digital cable - high-speed

RG-59 - Used as a patch cables, not for long distances