arp

[carl_townshend]

Hi all, can anyone tell me what routers use arp for? can they work without it? and also when we route a packet to the next hop router, does the router A need to know router B mac address to route the packet ?

[senthil_kumarpv]

Hi

As per my knowledge No it wont work without it

when a router receive a packet ,it will check the destination address in order to looking for routing table after that it will throw the packet via outgoing interface accordingly.

How it knows the outgoing interface ,where the Mac address comes to the picture , it will be the Mac of the next hop in the routing table

Regards,

Senthil

[Nagendra Kumar Nainar]

You need ARP only When the outgoing interface is an Ethernet interface as the router needs to know the MAC address of the next hop.