RE: Notes about identifier - locator separator

["Christian Huitema" <huitema@windows.microsoft.com>]

> The presence of IPv4 options in a packet header cause the IPv4
> packet to be kicked out of the silicon-path of many of today's
> high speed routers. Given that history, I could easily forsee
> a silicon-forwarder for IPv6 that kicks packets to the slow
> path if the next-header field is _not_ one of several known
> values (on the theory that if the next header is not X, Y, or Z
> then there _might_ be something in there that the router needs
> to look at...). This has undesired effects on throughput.

The IPv6 architecture is pretty clear about that one: the only packets
that a router is expected to process are those in which the first
payload is a "per hop option", or those in which the destination address
is one of the router's own addresses. All other payloads are supposedly
end-to-end.

-- Christian Huitema