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Re: What is the differents between Switch and Router?

2001-03-17 10:40:04


Randy Bush wrote:

A router decrements the IP TTL field.
It should also not propagate broadcast IP packets (subnet or all 1's).
for a non-attached subnet, what is a broadcast packet?
Maybe he meant directed broadcast as in 10.10.255.255 ?

i guess i was too suble.  from here, i do not know that 10.10.255.255 is not
a host in subnet 10.0.0.0/10.

I meant "subnet directed broadcasts", the rule I was referring to was RFC2644.

I was insufficiently specific:

        1. MUST NOT propagate IP packets whose destination is 
           broadcast (all 1's). (as in RFC1812) 

        2. MAY NOT propagate IP packets whose destination is 
           subnet broadcast for one if its attached nets (as in RFC2644)
                MUST be configured NOT to propagate as a default.
                MUST require explicit user intervention to override the default.

        2. MUST NOT propagate packets whose source address is the 
           subnet broadcast for one of its attached nets. (as in RFC2644)

We're all talking about the same "broadcast filter" rule (set).

Other than refining that rule, are there any other observable differences
between routers and switches?

Joe