Subject: [pim] Robert Wilton's No Objection on draft-ietf-pim-igmp-mld-extension-06: (with COMMENT)

From: Robert Wilton via Datatracker <[email-masked]>
Date: Mon, 31 Jan 2022 06:54:38 -0800

Robert Wilton has entered the following ballot position for
draft-ietf-pim-igmp-mld-extension-06: No Objection

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COMMENT:
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Hi,

Thanks for this document.  I found the use of the term "extension" to perhaps
not be as clear as it could be.  In most places the reference is to Extension
in the singular, and the attributes carried within the extension as TLVs. 
However, section 5 talks of "as new extensions are defined".  I presume that
what is meant here are "new extension TLVs" and not a different new Extension
to replace the Extension defined in this document.

Related to the ambiguity above, although the document makes it clear how an
implementation is expected to behave if it doesn't understand the "extension"
format, it doesn't define how an implementation should behave if it receives an
extension TLV that it doesn't understand.  I presume, for backwards
compatibility, that the default behavior is that receivers MUST ignore
extension TLVs that they don't understand and I think that needs to be
specified here.

Thanks,
Rob