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From: art@opal.acc.com (Art Berggreen)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: TCP/IP, SNMP, and Bridges
Message-ID: <1991May10.231601.27406@salt.acc.com>
Date: 10 May 91 23:16:01 GMT
References: <1991May10.054816.3039@avatar.com>
Sender: news@salt.acc.com
Reply-To: art@opal.acc.com (Art Berggreen)
Organization: Advanced Computer Communications, Santa Barbara, California
Lines: 24

In article <1991May10.054816.3039@avatar.com> kory@avatar.com (Kory Hamzeh) writes:
>
>If I have a TCP/IP stack running on a MAC layer bridge to support SNMP, must the
>ethernet interfaces have unique IP addresses?
>
>What if the device was an IP bridge or router?

If the device is BRIDGING IP datagarams, then the device should act as
if it was a host somehow attached to the bridged network.  In this mode,
the device has a single IP address on the logical IP network being
run over the bridged network.  If more than one logical IP net is being
run on the bridged net, then the node MAY have more than one IP address.
It is up to the bridging software to properly forward any internally
generated packets out the correct MAC level port(s).

If the device is ROUTING IP datagrams, then each MAC level interface
should have one (or more) IP addresses associated with the logical IP
nets defined separately on each MAC level network.

If the device is ROUTING on SOME ports and BRIDGING on the OTHER ports,
then a mix of both above mechanisms is used (and the details get very
messy).

Art