Network Fundamentals Flashcards
Fundamentals from ITPRO
Name The command line Commands to see the ip address configurations
Ipconfig
ifconfig - linux
ip address - latest linux
trongest encryption level possible using PSK without utilizing an additional authentication server. What encryption type should be implemented?
Since he wishes to use a pre-shared key and not require an authentication server, WPA personal is the most secure choice. If WPA2 Personal were an option, it would be more secure, though. WPA2 Enterprise is incorrect since the requirement was for a PSK, whereas WPA2 Enterprise requires a RADIUS authentication server to be used with individual usernames and passwords for each client. MAC filtering does not use a password or preshared key. WEP uses a pre-shared key to secure a wireless network, but WPA uses a stronger encryption standard than WEP.
You are working as a network administrator and are worried about the possibility of an insider threat. You want to enable a security feature that would remember the Layer 2 address first connected to a particular switch port to prevent someone from unplugging a workstation from the switch port and connecting their laptop to that same switch port. Which of the following security features would BEST accomplish this goal?
Port security, also known as persistent MAC learning or Sticky MAC, is a security feature that enables an interface to retain dynamically learned MAC addresses when the switch is restarted or if the interface goes down and is brought back online. This is a security feature that can be used to prevent someone from unplugging their office computer and connecting their laptop to the network jack without permission since the switch port connected to that network jack would only allow the computer with the original MAC address to gain connectivity.
Applications layer
Upper Layer
Provides application network access
dhcp, dns, ftp, smtp, pop3
presentation layer
Upper Layer
Formats application
ssl, ssh, compression, encryption, decryption, encoding
session layer
upper layer
establishes, maintains and terminates session communication
netbios, rpc, smb, sockets
Transport layer
lower layer
tcp/udp
sequencing and segmentation unless UDP
Network Layer
lower layer
Routing, Logical Addressing
IP,ICMP,NAT,OSPF
Data Link Layer
lower layer
flow control, acknowledgements,
detection
determine access to the media
sub layers:
Logical Link control(LLC)
Media Access Control(MAC)
Ethernet, ATM, MPLS, PPP, STP
Physical
Lower Layer
Electrical and Mechanical
Copper, Fiber, IEEE, 1394, BASE standards
how many headers on a Frame
layer 6 through layer 2 and then its handed off to be sent across physical media
data unit on network/data link
packet on the network
frame on the data
data on layer 7
payload - the data as it begins the encapsulation process as it moves down the osi stack
what is being added to the data on layer 4
the tcp/udp headers are added
what is being added to the data on layer 3
ip header
what is being added to the data on layer 2
Ethernet Header
What is an MTU?
The size of the frame
Network Topologies
the way links and nodes are arranged
the layout of the components that make up a network
Topology:
backbone cable
nodes are linking in
terminators on both ends
Vampire taps
broadcasts to all machines
Bus
Topology
connected in a circle or token
deterministic
Talking Stick
one computer goes down and they all go down
Ring
Topology
all devices are connected to the central device
if a node goes down it doesnt drop the signal
there is a single point of failure
Star
Can WAN’s connect other LAN’s together?
YES
MPLS Network
Multiple networks connected through the ISP’s network
Storage that is needed to be accessed at high speeds across the network when people need Data fast and quick
Storage Area Network(SAN)
Creating a logical representation of a component through software or
recreating a pc part in a virtual environment
Virtualization
- virtual machines
-virtual network devices
-virtual network devices such as firewall, switches, or routers
UTP
Unshielded Twisted Pair
how many pairs and wire conductors?
4 Twisted pairs
8 wires or conductors
cat3
cat4
cat5 fast ethernet
10mbps 100 meters 328ft
16mbps 100 meters 328ft
100mbps meters 328ft
what are cat3’s still used for
telephone cables
Cat5e Gigabit Ethernet
1GBPS 100meters/328ft
CAT6 Gigabit Ethernet
Cat6A gigabit
1gbps 100 meters(55 meters for 10gbps)
1gbps 10gbps 100 meters
BNC connector
twist to lock connectors
connecting T connectors
Greatest distance of bounded media
Core Diameter = 9 Microns
cladding 125 microns
Single Mode of bounded media
shorter distance than single mode
core = 50 or 62.5
cladding 125 macron
MMF(multimode Fiber)
SC connection
LC connector or little connector
Straight tip
MTRJ connector
measure of the transfer of bits across the media over a given period of time
Throughput
the capacity of a medium to carry data
Bandwidth
replaced the old GBIC’s
also in quad form as well
SFP or small form factor plug
theres a plus variant as well
CWDM
Course Wavelength Division multiplexing
supports 18 wavelengths per fiber
shorter distances
cheaper
DWDM
Dense Wavelength Division Multiplexing
supports up to 96 wavelengths per fiber
supports greater channel density at greater distance
wavelengths are 0.8nm apart
IEEE 802.3
Ethernet standard
defines CSMA/CD
many revisions over the year
cabling follows BASE standards
copper
CSMA/CD
Listens to see if data is being transmitted before sending data
fiber
Patch Panel
Connects a wall jack to a patch panel then to a switch or ISP
Remote Connections
SSH 22
Telnet 23
RDP 3389
SMTP 25
POPv3 110
IMAP 143
SMTPS 587 (TLS)
IMAPS 993 (SSL)
POP3S 995 (SSL)
Websites
HTTP 80
HTTPS 443
SQL related
SQL Server 1433
SQLNet 1521
MySQL 3306
Network Services
DHCP 67/68
DNS 53
NTP 123
SNMP 161/162
LDAP 389
LDAPS 636
Syslog 514
SIP 5060/50611
IP protocol types
Internet Control Message Protocol (ICMP)
TCP
UDP
Generic Routing Encapsulation (GRE)
Internet Protocol Security (IPSec)
AH
ESP
what service is used to set ip addresses
dhcp 67/68
dora
discover
offer
request
ack
the process to get the ip address from the server
ip helper address
dhcp relay
channel 1,6, 11
2.4ghz range
OSI layer responsible for translating and formatting information
presentation
adding a header and a footer to data
Data Encapsulation
Data Encapsulation occurs at which layer
data link
what is the purpose of TCP/IP
to control the flow of internet. Transmission Control Protocol is responsible for handling and controlling data flow
file transfer related ports
ftp 20/21
sftp 22
tftp 69
