Re: Applying the inet6 ND state engine to inet4

[Ted Lemon <mellon%fugue.com@localhost>]

If you’re going to do that, why not split it out of the kernel entirely? ND is many good things, but one of the things it is is fairly complicated, and not so latency critical that bouncing through userland is likely to be a problem.

> On Jul 12, 2020, at 4:57 AM, Roy Marples <roy%marples.name@localhost> wrote:
> 
> One of the really nice things about INET6 is Neighbour Discovery. Not really the on-wire protocol itself, but the state engine it has. The equivalent in ARP is not quite so nice.
> 
> I think it would be a good win to split the ND state engine out of netinet6 and into net to make it protocol agnostic (which it already is to some extent thanks the the LLE work done prior).
> 
> Why is this a good win? Well, the ARP state relies on the net.inet.arp.keep timer of 20 minutes where it thinks that once resolved the host *will* be up for 20 minutes. ND on the other hand sets short timers based on the flow of data so we can readily detect hosts becoming unreachable a lot faster.
> 
> Thoughts?
> 
> Roy