Path: utzoo!attcan!uunet!husc6!rutgers!ucsd!ucbvax!VENERA.ISI.EDU!prue
From: prue@VENERA.ISI.EDU
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Multiple TCP/IP servers on one host
Message-ID: <8809151736.AA01161@fji.isi.edu>
Date: 15 Sep 88 17:36:29 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 25

>>  1)  If the second path was 25% of the speed of the first path then 25% of
>>      the packets could be sent that way.  [...]
>>      if the two end sides were running the Van Jacobsen/Mike Karels code
>>      I believe this wouldn't be to much of a problem.  [...]
>
>
>The first thing (splitting load among routes) would screw up the
>Jacobson/Karels improved TCP completely.  They get a big win by
>estimating the variance of the round trip time; using alternating
>routes for different packets would drive this variance way up, causing
>the timeout to be set high, causing long stoppages on lost packets.

I disagree.  The first path is four times as fast but has four times as 
many packets.  The link delay is only 1/4 the second line but the queuing 
delay is four times as great.  The variation of the delivery times for the 
five packets would be less than using a single line.  As the queue sizes go 
up the variation in the network delay goes up.

I do however agree with your other point, type of service routing could 
put the second path to very good use.

Requards,

Walt Prue
Prue@isi.edu