ARP

Question 1

ARP

Answer 1

Address Resolution Protocol, Used to resolve ip addresses into mac addresses, ip and mac are needed for network communication

Question 2

ARP Packet

Answer 2

On an ethernet frame: consists of an Ethernet Header with a destination address, source address, and type, followed by an ARP Request or Reply, followed by padding, and CRC

Question 3

ARP Request or Reply

Answer 3

The important information in an ARP Request or Reply are the source hardware, source protocol, Destination/Target Hardware, and Destination/Target protocol address

Question 4

ARP Cache

Answer 4

Table of all known IP Address to Mac address mappings. It can have items be removed over time. Includes both static and dynamically learned entries

Question 5

Gratuitous ARP

Answer 5

An ARP announcement to update other hosts ARP tables without the need for an ARP Request. Ex. Updating the network if a computer’s ip address changed recently.

Question 6

RARP

Answer 6

Reverse Address Resolution Protocol. Depreciated. Used to resolve MAC addresses into ip addresses and required server on every network to do it. Replaced by BOOTP and DHCP