Re: [mpls] Alia Atlas' Discuss on draft-ietf-mpls-residence-time-14: (with DISCUSS and COMMENT)

[Greg Mirsky <[e-mail]>]

Hi Alia,
thank you for your thorough review and the comments. Please find my
responses in-line tagged GIM>>.

Regards,
Greg

On Wed, Mar 1, 2017 at 3:05 PM, Alia Atlas <[e-mail]> wrote:

> Alia Atlas has entered the following ballot position for
> draft-ietf-mpls-residence-time-14: Discuss
>
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> The document, along with other ballot positions, can be found here:
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>
>
> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
>
> Thank you for a clear document.  I think that this should be a
> straightforward Discuss to better clarify.
>
> In Section 4.8.1, it says "The RTM Set sub-object contains an ordered
> list, from egress node to
>    ingress node, of the RTM capable nodes along the LSP's path." but the
> sub-TLVs (as most clearly
> indicated by "4.8.1.3.  Unnumbered Interface Sub-TLV" are actually meant
> to be a list of interfaces.
>
GIM>> I think that the text, e.g. by stating "The Length is always 12" and
the Figure 10 are clear that only one interface can be listed in the
sub-TLV.
And the same is true for other sub-TLVs.

> It isn't clear whether these are supposed to be the egress interface, the
> ingress interface, or just any
> interface

GIM>> In order for the process described in section 4.8 to work RTM node
MUST use the same ID in RTM_SET sub-TLV as in RRO subobject.

> - or why sending just a Router ID wouldn't be sufficient.
> There is no indication as to whether
> it is ok to include both the IPv4 and IPv6 address Sub-TLVs for the same
> node or how to select which one
> to use.
>
GIM>> Selection should follow election of ID for corresponding subobject in
RRO.

>
>
> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
>
> 1) I am disappointed that the sub-TLV needed for an OSPFv3 Extended LSA
> isn't defined.  While I understand that a normative reference isn't
> desirable - instead of "left for future study", it would be better to say
> that the sub-TLV should use the same format as in Sec 4.3 and that the
> type allocation and full details are left to a future document.   This is
> exactly how gaps are created for networks running only IPv6.   If
> draft-ietf-ospf-ospfv3-lsa-extend-13 were not waiting for implementations
> and had a clear time-frame for how and when to progress, this would also
> be a Discuss.
>
GIM>> I agree that your proposal narrows the gap for IPv6 extension for RTM
capability advertisement. Will apply the text you've suggested in the next
version. Hope OSPF WG agrees to this change.