D-Link DES-3326SRM, Руководство по эксплуатации продукта

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D-Link DES-3326S Layer 3 Switch
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.
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