[trill] Alvaro Retana's Discuss on draft-ietf-trill-rfc6439bis-04: (with DISCUSS)

["Alvaro Retana" <[e-mail]>]

Alvaro Retana has entered the following ballot position for
draft-ietf-trill-rfc6439bis-04: Discuss

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DISCUSS:
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Section 2.4 (Overload and Appointed Forwarders) talks about potential
Appointed Forwarders which are overloaded.  In IS-IS, a node with the
overload bit set "shall not" (ISO 10589) be considered for transit. 
However, the use of "SHOULD NOT appoint an RBridge in overload" and
"SHOULD re-assign VLANs from the overloaded RBridge" leaves a potential
hole in the proper forwarding of TRILL data packers.  Why aren't MUST
NOT/MUST used?  Is there something in the specific use of IS-IS by TRILL
that I am missing?

I think this should be an easy DISCUSS to clear; either point to the
piece I'm missing, or don't use an overloaded node.