Subject: [Bier] Suresh Krishnan's Discuss on draft-ietf-bier-isis-extensions-07: (with DISCUSS and COMMENT)

From: Suresh Krishnan <[email-masked]>
Date: Wed, 21 Feb 2018 17:37:36 -0800

Suresh Krishnan has entered the following ballot position for
draft-ietf-bier-isis-extensions-07: Discuss

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DISCUSS:
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* Section 6.2.  BIER MPLS Encapsulation sub-sub-TLV

This should be straightforward to fix but it is not clear if the label range is
allowed to wrap around (overflow) or not past the 20 bit space. e.g. is a
Label=2^20-X with a MSI of X or larger legal? I was hoping that RFC8296 would
have covered this but unfortunately it leaves it to this document (and the OSPF
document) to specify.

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COMMENT:
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* Section 4.2.

"When the Prefix Attributes Flags sub-TLV is present N flag MUST be set."

Given that RFC7794, which defines this sub-TLV, clearly mentions that setting
this flag is purely optional, is there a reason this is made mandatory? I do
not see any checking for this flag in the behavior.