Re: [Idr] Response to comments on generalized RT constrain solution

["Pedro Marques (roque)" <roque at cisco.com>]

Mach,

> 
> If there is no RT-constrain, yes,there will be no any confusion,
> because the
> RT space for different AFI/SAFI is actually seperated. The operator
> could
> assign RTs freely for a specific VPN without considering(and IMHO, it
> SHOULD
> NOT) any other type of VPNs.

I disagree. There are very strong practical reasons why the operator
would want to make sure it can determine the VPN from the RT. VPNs will
have different services (e.g. v4/v6/mcast) enabled on them and policy is
expressed in terms of VPNs. That includes policy in ASBRs, etc.
In practice and operator will want to assign RTs per VPN and not per
(AF, VPN). rt-constraint doesn't change this equation a bit.

On the other hand I see no harm in an informational document that states
that life is much simpler if RTs are assigned per VPN. For instance,
that document can state that one of the advantages is that when using
RT-constraint a single RT can express the VPN membership. I don't
believe this needs to be a "bis". But clarifying this point would be a
good thing. I'm sure the question will be posed again. It is the kind of
issue that is just bound to be raised periodically.

  Pedro.