Re: [Last-Call] Opsdir last call review of draft-ietf-lsr-flex-algo-23

[Peter Psenak <[e-mail]>]

Hi Linda,

the version 24 includes the new section about the number of flex-algos 
as you requested.

thanks,
Peter

On 22/09/2022 16:53, Linda Dunbar wrote:
> Peter,
> 
> Thank you! I've studied this draft in LSR WG multiple times. I had a difficult time thinking how a router computing the paths when receiving 100+ topologies for one IGP domain, until being told most deployments only having handful of topologies.
> 
> Linda
> 
> 
> -----Original Message-----
> From: Peter Psenak <[e-mail]>
> Sent: Thursday, September 22, 2022 2:57 AM
> To: Linda Dunbar <[e-mail]>; [e-mail]
> Cc: [e-mail]; [e-mail]; [e-mail]
> Subject: Re: Opsdir last call review of draft-ietf-lsr-flex-algo-23
> 
> Hi Linda,
> 
> On 22/09/2022 00:24, Linda Dunbar via Datatracker wrote:
>> Reviewer: Linda Dunbar
>> Review result: Has Nits
>>
>> I have reviewed this document as part of the Ops area directorate's
>> ongoing effort to review all IETF documents being processed by the
>> IESG.  These comments were written primarily for the benefit of the Ops area directors.
>> Document editors and WG chairs should treat these comments just like
>> any other last call comments.
>>
>> This document specifies a set of extensions to IGP to enable multiple
>> topologies within one IGP domain, and each topology has its unique
>> constraint-based path computation metric.
>>
>> It would be very helpful if Section 15 (Operational Consideration)
>> included some considerations on the number of topologies to be created
>> for exemplary deployments. Even though theoretically,
>> hundreds/thousands of topologies can be supported by the mechanisms
>> described in the draft, in practice, probably only a handful of (or
>> even fewer) Flex-Algorithms are needed per IGP domain. It would be so
>> much easier to follow the document if knowing only two or three Flex-Algorithm are needed.
> 
> the maximum number of flex-algos is determined by the algorithm range that is (128-255), as specified in section 4 of the draft:
> 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdatatracker.ietf.org%2Fdoc%2Fhtml%2Fdraft-ietf-lsr-flex-algo-23%23section-4&amp;data=05%7C01%7Clinda.dunbar%40futurewei.com%7C1f01cedc0b8b47ea277808da9c6fff8f%7C0fee8ff2a3b240189c753a1d5591fedc%7C1%7C0%7C637994302096955841%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=tZyj49cl6PorH91QIoebPQ8PcTTWKGNJwDaCIel2GEE%3D&amp;reserved=0
> 
> 
> I can add a sentence in the draft saying that the expected deployment is to use only a subset of those.
> 
> thanks,
> Peter
> 
>>
>> Thank you
>> Linda Dunbar
>>
>>
>>
> 
>