On Fri, Sep 30, 2011 at 12:38 PM, Nick Hilliard <n...@foobar.org> wrote: > On 30/09/2011 17:30, Christopher Morrow wrote: >> traceroute is really an example of 'packet expired, send >> unreachable'... that, today is basically: >> o grab 64bytes of header (or something similar) >> o shove that in a payload >> o use the src as the dst >> o stick my src on >> o set icmp >> o crc and fire >> >> there's not really any need to do this in the slow path, is there? > > there are unconfirmed rumours that icmp ping and traceroute are handled by > hardware on the asr1k. I don't know if they are true. But you're right -
some platforms do some/all of this in hardware, yes. (I forget the matrix) > it would be good to support this without resorting to hammering the routing > engine. I don't really like the idea of punters running traceroutes > reducing my bgp convergence time. this is exactly why punting anything NOT management and/or routing-protocols should be banned. Thanks for making that point explicitly. -chris