Re: Help !

Tech-Archive recommends: Speed Up your PC by fixing your registry

From: GW (GW_at_discussions.microsoft.com)
Date: 10/30/04 

Date: Fri, 29 Oct 2004 18:19:02 -0700

HI Gerald,

Actually, I dont know how to explain it. There are 500 PCs
and 15 VLANs in my LAN. I can detect the IP address from mac
address if i console every of my switches. The problem is I want to find out
what is the IP address from one MAC address
given and it is not outside of my LAN or behind the router by using a
windows command line. I failed to get it.

Do you have any other suggestion?

"Gerald Vogt" wrote:

> GW wrote:
> > I dont get you. I just know the MAC address, how can I ping
> > the broadcast address?
>
> You do know your IP address and your network mask thus you can ping the
> IP broadcast address for your local network. All connected computers in
> your network should respond to this which fills your arp cache.
>
> Just to make it clear: you have only access to MAC addresses in your
> LAN. MAC addresses to not cross routers, gateways or other level 3
> devices. Therefore you cannot find out MAC addresses of devices behind
> the router. This is not possible and thus it is not possible to find out
> the IP addresses of devices behind a router if you only know the MAC
> address (which you know then probably know because you went to the
> device and wrote it down.)
>
> But maybe you should just explain in what setting you are trying to
> figure it out...
>
> Gerald
>

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