Path: utzoo!dciem!nrcaer!scs!spl1!laidbak!att!pacbell!ames!pasteur!ucbvax!GNOME.CS.CMU.EDU!Ravinder.Chandhok
From: Ravinder.Chandhok@GNOME.CS.CMU.EDU (Rob Chandhok)
Newsgroups: comp.protocols.appletalk
Subject: Re: Do FastPaths isolate broadcasts?
Message-ID: <849.581266019@GNOME.CS.CMU.EDU>
Date: 2 Jun 88 14:46:59 GMT
Article-I.D.: GNOME.849.581266019
References: <6139@well.UUCP>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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>Jeff Meyer at Fluke asked whether K-boxes pass throught the burst
>of packets that occur at startup time, thereby clogging up ethernet.  The
>burst of packets comes from the need to do a node address bid.  These are
>3-byte LAP packets that seek to ensure that no other device has the node
>address that the newly-booted device intends to use.  The node address
>only has to be unique within the zone (defined by the K-box usually).
>The Kinetics box does not need to pass on the packets and does not.
>-- 
>Kurt VanderSluis		Voice:  (415) 849-2331

One more time, with feeling.  The broadcast burst is LOCAL TO THE CABLE.  It
has nothing to do with zones, or nets, just node numbers.  It is a LAP level
braodcast, which does not get forwarded by the gateway (KBox).  LAP only
knows about node numbers, you need DDP to use a net number.   In general,
the "node address bid" is a local cable hardware broadcast, which is why
there is a problem on Ethernet if you use something like a LanBridge and
EtherTalk.

Rob