[I2nsf] Éric Vyncke's Discuss on draft-ietf-i2nsf-capability-data-model-12: (with DISCUSS and COMMENT)

[Éric Vyncke via Datatracker <[e-mail]>]

Éric Vyncke has entered the following ballot position for
draft-ietf-i2nsf-capability-data-model-12: Discuss

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DISCUSS:
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Thank you for the work put into this document.

While I do appreciate that a data model (this document) is derived from an
information model, I am concerned that the information model is an expired
draft whereas I would expect the information model being published first. Else,
what is the use of the information model ? What was the WG reasoning behind
'putting the cart before the horses' ? My concern is that by publishing the
YANG model, there is nearly no way to change the information model anymore.

Please find below a couple of non-blocking COMMENT points but also a couple of
blocking DISCUSS points around IPv6. They should be easy to resolve. I would
hate to have NSF having basic IPv6 capabilities that cannot be configured by
using the YANG model of this document.

I hope that this helps to improve the document,

Regards,

-éric

== DISCUSS ==

-- Section 4.1 --

It is quite common to apply conditions based on the whole IPv6 extension header
chain (i.e., presence of destination option header or wrong order of the
extension headers). Why is there no such capabilities in this YANG module ? The
only one is 'identity ipv6-next-header' that applies only to the first
extension header.

What is the difference between 'identity ipv6-protocol' and 'identity
ipv6-next-header' ? There is no 'protocol' field in the IPv6 header.

While fragmented IPv4 packets are part of the conditions ('identity
ipv4-fragment-flags'), there is no equivalent in IPv6.


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COMMENT:
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-- Section 4.1 --
May be am I misreading the YANG tree, but, I see no 'sctp-capability' in the
set of 'condition-capabilities' (even is SCTP is not heavily used).

Is there a real reason to have two related containers ?
generic-nsf-capabilities and advanced-nsf-capabilities. Why not a single one ?

Unsure what is meant by 'range' in 'identity range-ipv*-address'. Usually,
addresses are filtered/matched by using a prefix length and not a range (that
is difficult to implement in hardware).

Is there a reason why ICMP(v6) codes are not part of the conditions ?