Experiences with IPv6 and Routing Efficiency
nick at foobar.org
Sun Jan 19 16:11:07 UTC 2014
On 19/01/2014 04:00, Mukom Akong T. wrote:
> Have you found them to be more troublesome to process than IPv4 options
The problem is that you can have long EH chains, with one after another.
Generally speaking, most hardware forwarding engines will perform a lookup
based on the first N bytes of a packet.
If arbitrary length EHs are not supported by the hardware, then you have 3
options: forward the packets unilaterally, drop the packets unilaterally or
punt to a cpu/npu. Punting and forwarding both open up denial of service
attacks for hardware-forwarded routers, so generally the only sensible
option is to drop packets with long EH chains.
More information about the NANOG