TCP/IP Basics Chapter 6

Question 1

What does the command line Address Resolution Protocol (ARP) do?

Answer 1

Protocol used with CMD line command to determine mac address of a an ip address.

CMD command: arp

Question 2

What is a subnet mask?

Answer 2

The value used in tcp/ip settings to divide the ip address of a host into its component parts. Which are network id and host id

Question 3

Define Class A Ip Address

Answer 3

First Decimal Value: 1-126
Addresses: 1.0.0.0 - 126.255.255.255
Host per network ID: 16,777,216

Binary Octet Begins with: 0

Question 4

Define Class B IP Addresses

Answer 4

First Decimal Value: 128-191
Addresses: 128.0.0.0 - 191.255.255.255
Host per network ID: 65,534

Binary Octet Begins with: 10

Question 5

Define Class C Ip Address

Answer 5

First Decimal Value: 192-223
Addresses: 192.0.0.0 -223.255.255.255
Host per network ID: 254

Binary Octet Begins with: 110

Question 6

Define Class D IP Addresses

Answer 6

First Decimal Value: 224-239
Addresses: 224.0.0.0 -239.255.255.255
Host per network ID: multicast

Binary Octet Begins with: 1110

Question 7

Define Class E Ip Addresses

Answer 7

First Decimal Value: 240-255
Addresses: 240.0.0.0 - 255.255.255.255
Host per network ID: experimental

Binary Octet Begins with: 1111

Question 8

What is classful?

Answer 8

IPv4 address scheme that relied on original class blocks such as Class A, they are obsolete

Question 9

What is Classless?

Answer 9

IPv4 addressing scheme that does not rely on the original class blocks.

Question 10

What is CIDR?

Answer 10

Classless Inter-Domain Routing
The basis of allocating and routing classless addresses, not restricting subnet masks to /8 /16 or /24 which classful addressing did

Based on variable-length subnet masking where subnets can be allocated according to the needs of an organization

Question 11

What is Subnetting?

Answer 11

Taking a block of ip addresses and chopping them into multiple smaller groups!

Question 12

What is difference between static and dynamic IP addresses

Answer 12

Static: Assigning ip addresses by manually typing them into a computer
Dynamic: Way for computer to receive IP information automatically from a server program DHCP

Question 13

What is DHCP?

Answer 13

Dynamic Host Configuration Protocol

Sets TCP/IP settings for a client automatically on a network

Question 14

Which port does DHCP use?

Answer 14

Server UDP 67
Client UDP 68

Question 15

What is the DHCP 4-way handshake?(DORA)

Answer 15

DISC
OFR
REQ
ACK

DORA

Question 16

What is a DHCP Lease?

Answer 16

Created by DHCP Server to allow a system requesting DHCP IP information, to use that information for a certain amount of time.

Question 17

What is a DHCP Relay?

Answer 17

Router feature that when enabled accepts DHCP broadcasts from clients and sends them via unicast directly to the DHCP server. In common terms, DHCP communications can cross from one network to another if this is enabled.

AKA DHCP Relay Agent

Question 18

What is a DHCP Scope?

Answer 18

The pool of IP addresses the DHCP may allocate to clients requesting IP addresses or other IP information, like DNS server addresses.

Question 19

What is DHCP Snooping?

Answer 19

Switch process that monitors DHCP traffic filtering DHCP messages from untrusted sources. Typically used to block attacks that use a rouge DHCP server.

Question 20

What is the Automatic Private IP address (APIA)?

Answer 20

169.254.0.0/16
Networking feature in OS that enable clients to self configure an IP address and subnet mask automatically when a DHCP serve is not available.

Used if computer has issues getting an IP address from DHCP server

Can connect to other computers on network but cannot access internet.

Question 21

What is the loopback ip address?

Answer 21

127.0.0.1

Question 22

What are Private IP Address Ranges?

Answer 22

10.0.0.0 - 10.255.255.255 (1 Class A network Block)
172.16.0.0 - 172.31.255.255 (16 Class B Network Blocks)
192.168.0.0 - 192.168.255.255 (256 Class C network Blocks)

All other IP address are public IP address