Re: [Tsv-art] Tsvart last call review of draft-ietf-idr-te-pm-bgp-15

["Susan Hares" <[e-mail]>]

Alvaro: 

 

Yes – this is the format I was indicating – 

In some BGP-LS document I’ve seen tables that map the BGP-LS TLVs to the corresponding ISIS/OSPF TLVs — with the understanding that the format is different.  One such example is in §2.4/2.5 of draft-ietf-idr-bgp-ls-segment-routing-ext [1].  Is that the alignment you’re asking about?  If so, then I think that such a table would be useful.

 

This makes the implementations easier to create.  More importantly helps those who deploy the protocol additions to understand how to debug issues.   Having started out my Internet career as a OPS person, I like to see things that make life easier for the OPS/NM people.  We can comments in each draft or put pointers in a single draft (living or RFC).  … just wondering what would help.. 

 

I agree with your ADs comment on the text – that said 

 

“The semantic of the TLV is described in [RFC7810] and [RFC7471]” (in -14) to "The semantics of the value field in the TLV are described in [I-D.ietf-lsr-isis-rfc7810bis] and [RFC7471]” (in -15)…and the text about "TLV formats follow the rules defined in [RFC7752]” was added, as Les pointed out.  

 

Your comment makes the text correct. Thanks for catching that point. I thought Les already agreed to that change – so I did “ack” it or expand on it.   

 

 

Sue 

 

 

 

From: Alvaro Retana [mailto:[e-mail]] 
Sent: Friday, December 14, 2018 12:55 PM
To: Susan Hares; Les Ginsberg (ginsberg); Yoshifumi Nishida
Cc: [e-mail]; [e-mail]; [e-mail]; [e-mail]; [e-mail]
Subject: RE: Tsvart last call review of draft-ietf-idr-te-pm-bgp-15

 

On December 14, 2018 at 9:49:28 AM, Susan Hares ([e-mail]) wrote:

 

Sue:

 

Hi!

 

I think we might be talking about two different things…or I got lost, which is completely possible. :-)

 

I think Yoshi is asking about the format of the TLVs, which happens to be the same as the OSPF ones (rfc7471), but slightly different than ISIS (rfc7810bis): the type and length fields are different.  I had already pointed this out in my AD review, so the text changed from "The semantic of the TLV is described in [RFC7810] and [RFC7471]” (in -14) to "The semantics of the value field in the TLV are described in [I-D.ietf-lsr-isis-rfc7810bis] and [RFC7471]” (in -15)…and the text about "TLV formats follow the rules defined in [RFC7752]” was added, as Les pointed out.  I think this is enough.

 

When you say "align with IGP TLVs”, are you talking about the format of the TLV, or are you referring to something else?

 

In some BGP-LS document I’ve seen tables that map the BGP-LS TLVs to the corresponding ISIS/OSPF TLVs — with the understanding that the format is different.  One such example is in §2.4/2.5 of draft-ietf-idr-bgp-ls-segment-routing-ext [1].  Is that the alignment you’re asking about?  If so, then I think that such a table would be useful.

 

Thanks!

 

Alvaro.

 

 

[1] https://tools.ietf.org/html/draft-ietf-idr-bgp-ls-segment-routing-ext-11#section-2.4 

 

 

 

You both raised two sides of the issue regarding the BGP-LS TLVs when these TLVs align with IGP TLVs. 

 

Side 1: It is helpful to note that the TLVs are the same

Side 2: It is confusing to have this information in individual drafts.    

 

This is not a single draft issue but a concern regarding several drafts in the BGP-LS series from IDR.

 

Yoshi -  Would it help the clarity of the BGP-LS series to have an explanatory draft that indicates the places to find the alignment?  Or should we suggest a note to IANA registration to provide clarity.  

 

Thank you for raising both sides of this issue.   Your IDR chairs and AD have been discussing how to make this easier to understand for implementers and those who deploy the BGP-LS code.