Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!utgpu!water!watnot!watmath!clyde!rutgers!husc6!think!ames!ucbcad!ucbvax!GUNTER-ADAM.ARPA!AFDDN.TCP-IP
From: AFDDN.TCP-IP@GUNTER-ADAM.ARPA.UUCP
Newsgroups: mod.protocols.tcp-ip
Subject: Re: Packet network reliability
Message-ID: <8704021904.AA08193@ucbvax.Berkeley.EDU>
Date: Thu, 2-Apr-87 13:33:26 EST
Article-I.D.: ucbvax.8704021904.AA08193
Posted: Thu Apr  2 13:33:26 1987
Date-Received: Sat, 4-Apr-87 15:49:33 EST
References: <8704021229.AA15774@jupiter.mitre.org>
Sender: daemon@ucbvax.BERKELEY.EDU
Distribution: world
Organization: The ARPA Internet
Lines: 19
Approved: tcp-ip@sri-nic.arpa

Paul,
  On the C/30 algorithm, I believe there are two occurences which can generate
an update.  One is the expiration of some timer which I've been told is 30 secs.
I seem to remember at one time the limit being around 15 secs.  
  The other occurence is in the case where a link is determined to be down.  I
made the assumption that as the total number of nodes and the connectivity
increases then the probability of link problems goes up.  Would it increase
linearly?  Would be an interesting study.
  I've always thought an interesting experiment would be to first determine an
estimated time for a routing update to propagate through the network.  Then
determine the time required for the Line Up-down Protocol to determine a link is
has either just went up or down and then generate the update.  Now place a few
unscrupulous individuals goegraphically widespread across the network on several
interswitch links.  Let these individual interupt the link at time T0 and 
then restore it at T0 + routing propagation time - LUP decision time.  How
much bandwidth could you forcibly use up with internal routing updates?
Ciao,
Darrel
-------