Re: Flow label versus Extension header - protocol itself

[Iljitsch van Beijnum <iljitsch@muada.com>]

[pruned CC list before my mail client runs out of memory...]

On 29-apr-2005 Francis Dupont wrote:

>    Why not adding a new extension header?

> => basically as there is no way to deal with a new extension header  
> without
> modifying code or more, this will kill all the boxes which are looking
> inside packets for good or less good reasons.

I don't think that in this stadium of IPv6 deployment this is that  
huge a deal.

Also, looks like RFC 2460 dropped the ball here. It actually draws  
extension headers as having a next header and a length field in a  
fixed place, but then doesn't say that all extension headers should  
look like that.

>    I think that at the moment I agree with you that flow labels  
> should be
>    used if the existing definitions of flow labels can be accomodated
>    (few though they are).

> => the problem with the overloading of flow labels is this should  
> likely
> break all other possible usages of flow labels (not a surprise).

Have you been reading other posts to this list the past week? I think  
they make it pretty clear that using the flow label for demux can be  
done without impact to other flow label use, at the cost of some  
extra complexity when selecting the flow label for a new session.