[sfc] Magnus Westerlund's Discuss on draft-ietf-sfc-serviceid-header-12: (with DISCUSS)

[Magnus Westerlund via Datatracker <[e-mail]>]

Magnus Westerlund has entered the following ballot position for
draft-ietf-sfc-serviceid-header-12: Discuss

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DISCUSS:
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This looks like a significant problem. If I have missed anything in any
reference this might be very simple to resolve. However, based on this document
and looking at RFC 8300 I think this document is lacking in discussion of the
packet size impact of using both dynamic size headers, as well as there are no
limits to how many are added. Thus, there are significant risk for this header
to increase the packet size so much that it doesn't fit the underlying layer.
And as Section 5 in RFC8300 identifies there are no general solution provided
in NSH. Thus, I really think this issues needs some discussion. Even if the
actual result of this is a requirement on the control plane, the issue exists
in the data plane and thus warrants discussion in this document.