Subject: IPv6 Fast Forward
To: None <,,>
From: Liam J. Foy <>
List: tech-net
Date: 02/28/2007 20:35:13
Hello folks,

The following patch integrates IPv6 Fast Forward into the
NetBSD kernel. It should apply to current just fine - if not
it'll be some minor nit which you can just directly report
to me and I'll roll a new patch.

You can control it via a new sysctl:

	sysctl -w net.inet6.ip6.forwarding=1 <- of course
	sysctl -w net.inet6.ip6.maxflows=256 <- new sysctl

(ip6.maxflows has a default of 256). Also, remember to build
your kernel with GATEWAY. ip6.maxflows of course controls how
many flows can be created.


IPv6 Fast Forward increases forwarding speed (especially on low
powered CPUs in embedded devices) by hashing/caching the
flow (a flow being from a src to a dst). You are basically limited by
the network card/driver. This is available in IPv4 and IPv6.

Thanks to matt@, joerg@ and christos@ for initial review (as always).

Usual paypal donations for a poor 19 year old student go to


		Liam J. Foy