[rbridge] Critical bits for options

[Dinesh G Dutt]

v6 rules are more complicated than we need, aren't they ? All we need is 
the ability for an Rbridge to say, "I don't support any options, but 
this frame has options which I understand are fine to ignore and so I'll 
process the frame in fast path AND not delete the options from the 
outgoing frame". This allows us to define options that can pass through 
transit Rbridges. If we don't do this, I'd say that options would in 
"dead in the water", pretty much like IP options.

Dinesh
Joe Touch wrote:
> A few lessons from IP (which we may or may not want to emulate):
>
> --------------------------
> V6 rules:
>
> - hop-by-hop options MUST come before E2E ones
>
> - unrecognized options have 4 variants indicated via flags:
> 	- silent pass (skip over silently)
> 	- silent discard
> 	- discard w/ICMP
> 	- discard w/ICMP iff source != multicast
>
> - an additional per-option flag indicates:
> 	- immutable en-route
> 	- mutable en-route (i.e., ignore in Auth)
>
> --------------------------
> V4 rules:
>
> - unrecognized options
> 	- silent pass
>
> -------------------------
>
> I'll note that IPv6 doesn't e have a summary bit about critical HBH
> options. I don't see why we would anticipate being more complex than
> IPv6 in this regard.
>
> IMO, the IPv6 rules are probably sufficient to use as-is.
>
> Joe
>
>
>   
> ------------------------------------------------------------------------
>
> _______________________________________________
> rbridge mailing list
> rbridge at postel.org
> http://mailman.postel.org/mailman/listinfo/rbridge
>   

-- 
We make our world significant by the courage of our questions and by 
the depth of our answers.                               - Carl Sagan