Arp - D-Link DES-3326 User Manual

24-port NWay Ethernet Switch User's Guide
A field in the TCP header indicates that a packet has been
fragmented, and other information aids in the reassembly of the
packets into the original data.
Gateways that connect networks of different packet size limits
split the large packets into smaller ones and forward the smaller
packets on their attached networks.

ARP

The Address Resolution Protocol (ARP) determines the MAC
address and IP address correspondence for a network device.
A local computer will maintain an ARP cache which is a table of
MAC addresses and the corresponding IP addresses. Before a
connection with another computer is made, the local computer
first checks its ARP cache to determine whether the remote
computer has an entry. If it does, the local computer reads the
remote computer' s MAC address and writes it into the
destination field of the packets to be sent.
If the remote computer does not have an ARP cache entry, the
local computer must send an ARP request and wait for a reply.
When the local computer receives the ARP reply packet, the
local ARP reads the IP MAC address pair, and then checks the
ARP cache for this entry. If there is an entry, it is updated with
the new information. If there is no entry, a new entry is made.
There are two possible cases when an ARP packet is received by
a local computer. First, the local computer is the target of the
request. If it is, the local ARP replies by sending its MAC IP
address pair back to the requesting system. Second, if the local
computer is not the target of the request, the packet is dropped.
102 Switch Management and Operating Concepts