Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!hao!husc6!ut-sally!tut.cis.ohio-state.edu!pritch
From: pritch@tut.cis.ohio-state.edu (Norm Pritchett)
Newsgroups: comp.dcom.lans
Subject: Re: LanBridge 100 multicast packets
Message-ID: <7269@tut.cis.ohio-state.edu>
Date: 26 Feb 88 14:12:00 GMT
References: <2070@saturn.ucsc.edu> <23864@yale-celray.yale.UUCP>
Organization: The Ohio State University Dept of Computer and Information Science
Lines: 29
Keywords: LB100 ethernet multicast

In article <2070@saturn.ucsc.edu> eshop@saturn.ucsc.edu (Jim Warner) writes: 
  Our campus net includes one DEC LB100 lan bridge.  The LB100 sends a
  packet a second of type 8038 to ether multicast address
  9:0:2b:1:0:1....Is this normal for an LB100?  Do nets that have ten
  LB100s have ten of these packets a second?  If we had RBMS, could we
  turn this off?  Do folks that have RBMS think it worth while?

In article <23864@yale-celray.yale.UUCP> leichter@yale-celray.UUCP (Jerry Leichter) writes:
  These are messages that LanBridges send to each other to discover the
  topology of their interconnections and build a spanning tree.  Yes,
  it's normal for them to do this.  If you had 10 LanBridges, each would
  indeed be doing it....

							-- Jerry
---------

Actually, the only time all ten would send the multicasts is during
startup while the spanning tree is being figured out.  After the
Bridges feel they have determined the layout of the other LANbridges
(or rather a part of determining the layout) a "root" bridge is
elected.  After all this negotiation, he is the only one who will
continue sending the multicast packets.  When he goes down everyone
starts in with the multicasts again to refigure the spanning tree
algorithm and elect a new root.


-- 
Norm Pritchett, The Ohio State University College of Engineering
ARPA: pritchett@eng.ohio-state.edu	BITNET: TS1703 at OHSTVMA
UUCP: cbosgd!tut.cis.ohio-state.edu!pritch