Ed Greshko wrote:
Mike McCarty wrote:
[snip]
So my Linux machine is asking for router's MAC address so it
can dump packets destined for the router?
Ahhh....no.....
It is asking for the MAC address so it can dump packets destined for the
*next hop*.
But my machine is not configured to be a router, bridge, or gateway.
Doesn't mean that it isn't prepared to be one, I know.
But why would it need the MAC for the router?
When it arrives at your router, the router determines that the IP
address in the IP portion of the header is not its IP address. It will
determine the next hop's MAC address...many different ways to do
this...and send the packet on its way. This is repeated over and over
until the *destination IP* address is reached.
Yes, my machine is the destination IP.
Umm, maybe a little more concreteness would help...
[PSTN]<-ADSL-LINE->[DSL MODEM]<-E-NET->[ROUTER]<-E-NET->[COMPUTER]
There is not and cannot be a "next hop". The computer is a terminal.
The only connection my computer has is to the router. I realize
that the setup does not necessarily take this into account.
So, can you tell me what message the computer is trying to
be able to dump, and how knowing the MAC address of the router
would help?
Is this because ethernet is broadcast? Again, ISTM that the
hardware could dump messages not destined for self at MAC
level. Messages which are temporarily destined for self
only for passing along to another device closer to the destination
need routing at IP level to get closer to destination, not
dumping.
Sorry if I seem dense.
traceroute www.google.com
will give you an idea of how many times that could happen.
I'm familiar with traceroute.
Mike
--
p="p=%c%s%c;main(){printf(p,34,p,34);}";main(){printf(p,34,p,34);}
This message made from 100% recycled bits.
You have found the bank of Larn.
I can explain it for you, but I can't understand it for you.
I speak only for myself, and I am unanimous in that!
