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What does arp 42 who has 192.168.1.1? tell 192.168.1.33 mean?

1

What does this mean?

arp 42 who has 192.168.1.1? tell 192.168.1.33"

asked 02 Aug '11, 17:18

Sandra%20Wolfe's gravatar image

Sandra Wolfe
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edited 02 Aug '11, 17:19

It seems my Samsung TV keeps sending these same ARP requests nonstop. what is weird is my samsung tv gets internet access just fine and when i check the Default Gateway on my TV it matches the default gateway of my router just fine. So are these non-stop requests normal?

arp 42 who has 192.168.1.1? tell 192.168.1.33"

(05 Jun '16, 07:45) Neoraj3

It should have probably been a separate Question. Nevertheless:

Various types of equipment use ARP requests to continuously monitor availability of LAN connection in general and the router in particular, i.e. they keep sending ARP requests even when it doesn't acutely need to send any data.

(05 Jun '16, 09:33) sindy

One Answer:

6

The host with IP address 192.168.1.33 wants to send some data. It knows it must send this data to 192.168.1.1, but it doesn't know the MAC address to send it to, so it has sent an Address Resolution Protocol (ARP) request to find out that information.

So, arp stands for "Address Resolution Protocol", and 42 is the number of bytes comprising this ARP packet. And since 42 is less than the minimum number of bytes for an Ethernet frame, it also means that you were capturing on the same machine that sent the ARP request, in this case, 192.168.1.33.

For more information about ARP, refer to sites such as:

answered 02 Aug '11, 19:47

cmaynard's gravatar image

cmaynard ♦♦
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accept rate: 20%