[Lsr] Comments on draft-hu-lsr-isis-path-mtu

"Les Ginsberg (ginsberg)" <ginsberg@cisco.com> Mon, 09 July 2018 04:52 UTC

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From: "Les Ginsberg (ginsberg)" <ginsberg@cisco.com>
To: "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>, Huzhibo <huzhibo@huawei.com>, "lsr@ietf.org" <lsr@ietf.org>
CC: "Dailongfei (Larry, IP Research)" <larry.dai@huawei.com>, Lizhenbin <lizhenbin@huawei.com>, "zhuyq@gsta.com" <zhuyq@gsta.com>
Thread-Topic: Comments on draft-hu-lsr-isis-path-mtu
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Date: Mon, 09 Jul 2018 04:52:00 +0000
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Subject: [Lsr] Comments on draft-hu-lsr-isis-path-mtu
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(Changed the subject – was “RE: [Lsr] IETF 102 LSR Working Group Call for Agenda Items”)

Zhibo –

Following up on Acee’s comment…he is (of course) quite correct that there already is a per link MTU sub-TLV defined by RFC 7176 – it is sub-TLV 28 defined here: https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-codepoints.xhtml#isis-tlv-codepoints-22-23-25-141-222-223

In reading your draft, it seems that what you want to advertise is a per link attribute – not a per node attribute – in which case the existing sub-TLV is a perfect fit.

Not at all clear why we would need a new TLV – nor how such a TLV would allow you to advertise a per-link attribute without repeating all of the context information (neighbor ID, link endpoint identifiers) already available in TLVs 22, etc.

Do you agree that IS-IS already has what is needed and therefore does not need any additional protocol extension?


From: Lsr <lsr-bounces@ietf.org> On Behalf Of Acee Lindem (acee)
Sent: Friday, July 06, 2018 6:21 AM
To: Huzhibo <huzhibo@huawei.com>; lsr@ietf.org
Cc: Dailongfei (Larry, IP Research) <larry.dai@huawei.com>; Lizhenbin <lizhenbin@huawei.com>; zhuyq@gsta.com
Subject: Re: [Lsr] IETF 102 LSR Working Group Call for Agenda Items

Hi Zhibo,

I’m sorry but our agenda is already full for IETF 102. As LSR is one of the most popular WGs, you need to get your requests in early. With respect to this draft, there is already an IS-IS sub-TLV MTU advertisement defined in RFC 7176. While the RFC is specific to TRILL, I don’t see any reason why the sub-TLV couldn’t be used in non-TRILL deploymennts.


From: Huzhibo <huzhibo@huawei.com<mailto:huzhibo@huawei.com>>
Date: Friday, July 6, 2018 at 3:08 AM
To: Acee Lindem <acee@cisco.com<mailto:acee@cisco.com>>, "lsr@ietf.org<mailto:lsr@ietf.org>" <lsr@ietf.org<mailto:lsr@ietf.org>>
Cc: "zhuyq@gsta.com<mailto:zhuyq@gsta.com>" <zhuyq@gsta.com<mailto:zhuyq@gsta.com>>, Robin Li <lizhenbin@huawei.com<mailto:lizhenbin@huawei.com>>, "Dailongfei (Larry, IP Research)" <larry.dai@huawei.com<mailto:larry.dai@huawei.com>>
Subject: RE: [Lsr] IETF 102 LSR Working Group Call for Agenda Items


Request a slot to discuss ISIS extended for PathMTU:

Presenter: ZhiBo Hu

Duration: 10 mins


From: Lsr [mailto:lsr-bounces@ietf.org] On Behalf Of Acee Lindem (acee)
Sent: Monday, June 18, 2018 9:45 PM
To: lsr@ietf.org<mailto:lsr@ietf.org>
Subject: [Lsr] IETF 102 LSR Working Group Call for Agenda Items

Hi Folks,

The LSR (link-state-routing) WG will be meeting on Monday, July 16, 2018 from 9:30 to 12:00 (the first WG slot of IETF 102).

Please send us (lsr-chairs@ietf.org<mailto:lsr-chairs@ietf.org>) any requests for presentation slots.