2.5 IP Addressing

Question 1

IP Address

Answer 1

A unique address that identifies a device on a network
Consists of two parts:
Network address: every network has a unique address
Host address: assigned to devices within the network (computers, servers, routers, etc)

Question 2

IPv4

Answer 2

• 32 bits long (four 8-bit segments)
• 4 different numbers separated by a period (.)
• max value for each byte is 255

Ex: 192.168.1.131

• loopback address: 127.0.0.1

Question 3

IPv6

Answer 3

• 128 bits long (eight 16-bit segments)
• hexadecimal format
• first 64 bits is the network prefix
• last 64 bits is the host address
• loopback address is 0:0:0:0:0:0:1 or ::1

Question 4

Public IP address

Answer 4

IP address used to access the Internet

Class A: 1.0.0.0 to 127.0.0.0
Class B: 128.0.0.0 to 191.255.0.0
Class C: 192.0.0.0 to 223.255.255.0

Question 5

Private IP address

Answer 5

Not routed on the internet and no traffic can be sent to them from the Internet. Only work within the local network

Class A: 10.0.0.0 to 10.255.255.255
Class B: 172.16.0.0 to 172.31.255.255
Class C: 192.168.0.0 to 192.168.255.255

Question 6

Subnet Mask

Answer 6

• 32-bit (or 128-bit) number used to divide your IP address into network and host portions
• identifies the subnet of a local device

Question 7

Default Gateway

Answer 7

Allows a user to access servers and devices outside of their network

Ex. Wi-Fi router

Question 8

Static IP address

Answer 8

IP address that does not change

Question 9

Dynamic IP address

Answer 9

• IP address is active for a certain duration and then “expires”
• IP can change every time the device connects to a network
• assigned by DHCP

Question 10

APIPA

Answer 10

Automatic Private IP Addressing:
- can only communicate with devices in the local network
- used when there is no DHCP server available or when the DHCP server fails to respond
- IP between 169.254.0.1 and 169.254.255.254
- used ARP to confirm the address isn’t currently in use

Question 11

DHCP process

Answer 11

DORA:
1. Discover: find a DHCP server on local network
2. Offer: DHCP server will offer an IP address to the device
3. Request: Device picks an offer and sends a request
4. Acknowledge: DHCP confirms the request and provides IP configuration settings

Question 12

Shortening IPv6 addresses

Answer 12

Segments containing only zeros can be shortened to two semicolons (can only be done once).
Leading zeros can be removed.
A hextet with 4 zeros can be shortened to a single zero
Ex.
fe80:0000:0000:0000:5d18:0652:cffd:8f52
can be shortened to
fe80::5d18:652:cffd:8f52