Re: arp command
the ARP command, Short for Address Resolution Protocol is used to translate IP addresses to mac addresses - Ill give ya some info on how it works. First computers on a local network communicate with frames, as a matter of fact all systems communicate with frames, Packets i will not go into now. Ok so a system needs to communicate by making a frame but frames are addresses to mac addresses so how does the system communicate without knowing this?, it sends out a special frame addressed to FFFFFF this is a unique frame and all computers proccess this frame. The frame then asks what is the mac address for IP XXX.XXX.XXX.XXX the machine with that mac address will then reply, now when u use the ARP command with the switch -a it will display all the times that it has needed to do this, in what we call its cache.
-Taken From Mike Meyers Managing and Troubleshooting networks book
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