Subject: [Gen-art] Gen-ART Telechat review of draft-ietf-rtgwg-remote-lfa-10.txt

From: Suresh Krishnan <[email-masked]>
Date: Wed, 7 Jan 2015 06:10:08 +0000

I am the assigned Gen-ART reviewer for this draft. For background on
Gen-ART, please see the FAQ at
<http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>

Please wait for direction from your document shepherd or AD before 
posting a new version of the draft.

Document: draft-ietf-rtgwg-remote-lfa-10.txt
Reviewer: Suresh Krishnan
Review Date: 2015/01/06
IESG Telechat date: 2015/01/08

Summary: This draft is ready for publication as a Proposed Standard but 
I have some minor issues that the authors may wish to address.

Section 4.2.1.1:
This sentence is missing a verb (reach?)

The exclusion of routers reachable via an ECMP that includes S-E 
prevents the forwarding subsystem from attempting to <MISSING VERB> a 
repair endpoint via the failed link S-E.

Section 4.3:

The Compute_Neighbor_SPFs() function seems to be missing a check for 
verifying if the interface is not the failed interface. I think the 
following check should be added.

if (intf != fail_intf)

Thanks
Suresh

---

From: Jari Arkko <[email-masked]>
Date: Wed, 7 Jan 2015 11:13:08 +0200

Thanks for your review, Suresh. I agree with your points. Authors, are you taking this into account?

Jari

On 07 Jan 2015, at 08:10, Suresh Krishnan <[email-masked]> wrote:

> _______________________________________________
> Gen-art mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/gen-art

---

From: Stewart Bryant <[email-masked]>
Date: Wed, 07 Jan 2015 11:49:30 +0000

Thank you for the review Suresh.

>> repair endpoint via the failed link S-E.
We will fix.
>> following check should be added.
It is certainly harmless to do the computation, and in an implementation
that runs all the SPFs and banks them it will be needed if you protect
one than one interface. The rest of the code assumes that you have
all SPFs available. So I am not sure whether it is more confusing
to put it in or leave it out. I am also trying to get my head round
whether there are any corner cases that need that information (ECMP
is normally the optimization killer).

My inclination is to leave out the if statement and allow the implementer
to find the optimization rather than risk forgetting some subtly.

I could put in a comment about running them all so you have the
information ready for the next interface that needs rlfa protection.

Stewart

-- 
For corporate legal information go to:

http://www.cisco.com/web/about/doing_business/legal/cri/index.html

---

From: Suresh Krishnan <[email-masked]>
Date: Wed, 7 Jan 2015 18:56:51 -0500

Hi Stewart,
   Thank you for the quick response. Your proposed changes work for me. 
One small comment inline.

>>> repair endpoint via the failed link S-E.

OK.

> to find the optimization rather than risk forgetting some subtly.

I am fine either way as long as the description and the code are not in 
conflict.

Thanks
Suresh

---

From: Stewart Bryant <[email-masked]>
Date: Thu, 08 Jan 2015 10:58:50 +0000

I agree, they must be aligned, let me see what the best way to fix it is.

Stewart

On 07/01/2015 23:56, Suresh Krishnan wrote:
> I am fine either way as long as the description and the code are not 
> in conflict.
>
> Thanks
> Suresh
>
> .
>