[rbridge] VLAN Scoping / MAC Uniqueness

[Caitlin Bestler]

Radia Perlman wrote:
> With IS-IS flooding, an RBridge can't simply scan the
> information for VLAN A and then delete it.
> It has to store it, since LSPs have to be flooded reliably,
> so each RBridge would have to keep all endnode information for all
> VLANs. 
> 

I'm not following. If an RBridge is using globally scoped MAC
addresses, and it receives endnode information for a VLAN that
it does not support, the only thing I can see that it would have
to do is to delete any information it had on the same MAC address
on a different VLAN.

It would never send to VLAN A, so why would it retain any information
once the contradictory data was eliminated? A deleted record can be
considered to be reliably delected, can't it?

If it's knowledge of MAC Addresses is VLAN scoped then nothing
about VLAN A is ever relevant. That is why it is a very simple
solution, but one that creates an RBridge requirement for scoped
learning that does not apply to simple Bridges.