Subject: do tcp, udp, and icmp's stacks communicate?
To: None <tech-net@NetBSD.ORG>
From: Andrew Brown <>
List: tech-net
Date: 03/24/1998 12:47:02
is there any way i can "affect" the tcp timeout/retry/retransmit
mechanism via another protocol?

eg, i have a tcp connection to a machine in the other side of a
"lossy" t1.  i think the router's bad (it loses 10-16% of a flood ping
from either the ethernet or the serial side even though other hosts on
both sides are almost 100% solid) but there's not much i an do about

it would be nice if some other tcp connection or a udp packet or an
icmp ping could somehow "wake up" the dying connection and revitalize

on a different note, i can't recall (brain is toast!) at this point
exactly how the timeoure/retransmit mechanism does it retrials.  if i
had a connection that was down the fourth out of every four seconds
(or just dropped all packets), how well would tcp deal with that?  is
it a sequential retry or some sort of sparser and sparser retry until
it finally gives up?  it seems to me (imsuo) that a backoff sequence
related to prime numbers might deal with such a thing much better.  it
would be much less likely to "harmonize" with the rythmic outages.

|-----< "CODE WARRIOR" >-----|             * "ah!  i see you have the internet (Andrew Brown)                that goes *ping*!"      * "information is power -- share the wealth."