Re: [Teas] Types within ietf-te-path-computation and ietf-te-types Modules
Igor Bryskin <Igor.Bryskin@huawei.com> Sun, 20 January 2019 16:01 UTC
Return-Path: <Igor.Bryskin@huawei.com>
X-Original-To: teas@ietfa.amsl.com
Delivered-To: teas@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 7A0F7127B4C for <teas@ietfa.amsl.com>; Sun, 20 Jan 2019 08:01:11 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.199
X-Spam-Level:
X-Spam-Status: No, score=-4.199 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id kYTDmZ3fmuxu for <teas@ietfa.amsl.com>; Sun, 20 Jan 2019 08:01:07 -0800 (PST)
Received: from huawei.com (lhrrgout.huawei.com [185.176.76.210]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 9329012426E for <teas@ietf.org>; Sun, 20 Jan 2019 08:01:06 -0800 (PST)
Received: from lhreml702-cah.china.huawei.com (unknown [172.18.7.107]) by Forcepoint Email with ESMTP id 5D30C470209329A88D2C for <teas@ietf.org>; Sun, 20 Jan 2019 16:01:04 +0000 (GMT)
Received: from SJCEML701-CHM.china.huawei.com (10.208.112.40) by lhreml702-cah.china.huawei.com (10.201.108.43) with Microsoft SMTP Server (TLS) id 14.3.408.0; Sun, 20 Jan 2019 16:01:03 +0000
Received: from SJCEML521-MBX.china.huawei.com ([169.254.1.96]) by SJCEML701-CHM.china.huawei.com ([169.254.3.31]) with mapi id 14.03.0415.000; Sun, 20 Jan 2019 08:00:55 -0800
From: Igor Bryskin <Igor.Bryskin@huawei.com>
To: "ietfa@btconnect.com" <ietfa@btconnect.com>, "sergio.belotti@nokia.com" <sergio.belotti@nokia.com>, Igor Bryskin <Igor.Bryskin@huawei.com>, "julien.meuric@orange.com" <julien.meuric@orange.com>, "teas@ietf.org" <teas@ietf.org>
CC: "esther.lerouzic@orange.com" <esther.lerouzic@orange.com>, "ahmed.triki@orange.com" <ahmed.triki@orange.com>, "tsaad@cisco.com" <tsaad@cisco.com>
Thread-Topic: [Teas] Types within ietf-te-path-computation and ietf-te-types Modules
Thread-Index: AQHUrLF+MRSI9pFT0EemCcHxg8dUFqW4WULJ
Date: Sun, 20 Jan 2019 16:00:53 +0000
Message-ID: <etPan.5c449bb6.8af89c7.fcb@localhost>
References: <38a2168c-b23d-0324-c058-72ce000a84b4@orange.com> <etPan.5c3dd203.5c1b45c5.2232@localhost> <etPan.5c3dead0.76c532e5.48f3@localhost>, <216f71fd-6cc0-ce1a-7da8-0adc4b38da98@orange.com> <etPan.5c3f2a50.63ff74c0.f8f@localhost> <AM0PR07MB59212DE755A64C1CB4756B63919C0@AM0PR07MB5921.eurprd07.prod.outlook.com>, <005601d4b0b8$a3be0f40$4001a8c0@gateway.2wire.net>
In-Reply-To: <005601d4b0b8$a3be0f40$4001a8c0@gateway.2wire.net>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
Content-Type: multipart/alternative; boundary="_000_etPan5c449bb68af89c7fcblocalhost_"
MIME-Version: 1.0
X-CFilter-Loop: Reflected
Archived-At: <https://mailarchive.ietf.org/arch/msg/teas/Gs1SAAdJTNQXbVT1SGsO9BsGBIw>
Subject: Re: [Teas] Types within ietf-te-path-computation and ietf-te-types Modules
X-BeenThere: teas@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Traffic Engineering Architecture and Signaling working group discussion list <teas.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/teas>, <mailto:teas-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/teas/>
List-Post: <mailto:teas@ietf.org>
List-Help: <mailto:teas-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/teas>, <mailto:teas-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 20 Jan 2019 16:01:12 -0000
Hi Tom, Lets consider Ipv6 only network. Why in your opinion one would ever nesd a 128b long TE Router ID? This would be necessary only if TE Router ID is one of the router's global IP addresses. But we seem to agree that TE Router needs to be neither IP address nor be global (just a TE topology unique, and there could be more than one TE topologies any given router could be part of with a separate TE Router ID/ te-node ID). And there are also, of course, abstact TE topologies, where TE Router IDs are meaningless, while te-node IDs are meaningful. My question is can you thInk of a practical use case that requires 128b TE Router ID? Probably is worth noting that In the te-topology modeling design team we have both CSCO and JNPR folks. None of them has ever raised any issues with 32b long te-node IDs AFAIK. Cheers, Igor From:tom petch To:Belotti, Sergio (Nokia - IT/Vimercate),Igor Bryskin,julien.meuric@orange.com,teas@ietf.org, Cc:esther.lerouzic@orange.com,ahmed.triki@orange.com,Tarek Saad (tsaad), Date:2019-01-20 07:07:59 Subject:Re: [Teas] Types within ietf-te-path-computation and ietf-te-types Modules ----- Original Message ----- From: "Belotti, Sergio (Nokia - IT/Vimercate)" <sergio.belotti@nokia.com> Sent: Friday, January 18, 2019 8:39 AM Hi Igor, I think Julien is not arguing about the need or not to have a routable address but on the fact that ,at the moment, te-types in the description of te-node-id mention RFC 6119 that means a 128-bit format. <tp> No it doesn't. As your extract below shows, the reference is to Section 3.2.1 of [RFC6119]. Go read it, it only defines a 32-bit stable IPv4 address; like the other references, 32 bits rules ok! Where TE might have problems is with a box that is: - TE - IPv6 only, no IPv4 - supports both LSR protocols - wants to follow the advice that the two LSR protocols should use the same identifier so that information can be correlated. OSPF then has Router Address 32-bit, no structure no semantics, the identifier Router IPv6 Address 128-bit in TLV Type 3 while the other LSR protocol has IPv6 TE Router ID 128-bit TLV type 140. so the two identifiers for the two LSR protocols would appear to be irreconcilable. This is a TE issue, not a modelling one; if the TE is in a seemingly impossible situation, then the YANG module too will be in a seemingly impossible situation and it is the TE that needs to be resolved first before the YANG module can be. Tom Petch "typedef te-node-id { type yang:dotted-quad; description "A type representing the identifier for a node in a TE topology. The identifier is represented as 32-bit unsigned integer in the dotted-quad notation. This attribute MAY be mapped to the Router Address described in Section 2.4.1 of [RFC3630], the TE Router ID described in Section 3 of [RFC6827], the Traffic Engineering Router ID described in Section 4.3 of [RFC5305], or the TE Router ID described in Section 3.2.1 of [RFC6119]. The reachability of such a TE node MAY be achieved by a mechanism such as Section 6.2 of [RFC6827]."; Cheers Sergio From: Teas <teas-bounces@ietf.org> On Behalf Of Igor Bryskin Sent: Wednesday, January 16, 2019 1:56 PM Hi Julien, To your A2.1: te-node-id (a property of a te topology node) is conceptually different/orthoganal from TE-router-id ( a property of a TE enabled routing protocol speaker). There are many reasons to this, to name a couple: 1. Tthere could be TE networks (especially in cs layers) that are run without routing protocols; 2. TE topology could be abstract with a te-node representing an arbitrary segment of the underlay network. TE routing is just one way (albeit important) a te topology could be discovered/managed and the RFCs you mentioned are as important for te topologies as,say, RSVP RFCs are important for te tunnels, i.e. we can onlly talk about reference points and convenience of implementaion of popular use cases, but not something that needs to be comformant to universally. To your B1.1: Tunnel termination point normally represents a physical device where a TE tunnel is terminated, its clients are adoptrd, etc. (e.g. WDM transponder) with a certain phyisical address, which may or may not fit in 64, 128, etc. bit, hence the type is defined as binary. On the other hand, link termination point (or tp per I2RS topology model) is a numbered or unnumbered identifier of a link terminated on a node. There is no need for sharing types between the two because they are totally unrelated. Cheers, Igor From:Julien Meuric Date:2019-01-16 04:49:41 Hi Igor, A.1. I'm glad we agree on using the "te-node-id" type in both places. A.2. I am not questioning the fact that an ID does not need to be a routable address; I am just saying that there are (Standard Track) RFCs that defines 128-bit TE Router IDs (e.g., RFC 6119 section 4.1, as mentioned below) and the definition of "te-node-id" imported from "te-types" cannot overlook that (this could be another thread directed to the authors of ietf-te-types). B.1. I agree that a tunnel TP is different from a link TP; I do not suggest to use the same name on these leaves. However, both should point to the "te-tp-id" space (instead of binary). If you believe there are some missing encodings in "te-tp-id", what are they? B.2. It is fine to have 2 different types such as "te-node-id" and "te-tp-id" (as within the RO part in the tree below), we are in sync on that. Cheers, Julien On 15/01/2019 15:12, Igor Bryskin wrote: > Hi Julien, > > Two more comments from me and Italo: > 1.To <http://1.To> align src/dst type with the node-id type is a good > idea; > 2. As widely discussed, TE node id, generally speaking, is not > (pingable) IP address, nor it is a routing protocol router ID , just > a number that identifys node uniquely in the TE topology the node > belongs to, hence uint32 is sufficient. > > Cheers, > Igor > *From:*Igor Bryskin > *Date:*2019-01-15 07:27:22 > > Hi Julien, > > 2 comments: > 1.src (dst)-tp-id below means src/dst tunnel termination point, which > is different from flink-tp-id below, which menas link termination > point, i.e. place where a numbered/unnumbered link is terminated on a > node; > 2. We discussed a lot and believe that node-id sub-object should be > different from numbered link-id sub-object ( as per current RSVP and > PCEP) because there are use cases where one needs to distinguish node > from link in ERO without necessarily looking into topology infotmation.. > > Cheers, > Igor > *From:*Julien Meuric > *Date:*2019-01-15 04:05:43 > > Hi all, > > A colleague of mine has started to implement some pieces of the > ietf-te-path-computation Yang module. He has already bumped into a > couple of inconsistencies that are worth sharing. > > In this module, we have: > > +---- path-request* [request-id] > | +---- ... > | +---- source? inet:ip-address > | +---- destination? inet:ip-address > | +---- src-tp-id? binary > | +---- dst-tp-id? binary > | +---- ... > | +---- explicit-route-objects > | | +---- route-object-exclude-always* [index] > | | | +---- index uint32 > | | | +---- (type)? > | | | +--:(num-unnum-hop) > | | | | +---- num-unnum-hop > | | | | +---- node-id? te-types:te-node-id > | | | | +---- link-tp-id? te-types:te-tp-id > | | | | +---- ... > > In the above, the types associated to source/destination and x-tp-id are > different between the request level and the RO level. This leads us to 2 > fixes to consider on this document: > - src-tp-id/dst-tp-id should mimic link-tp-id and reuse te-tp-id instead > of binary; > - source/destination and node-id should share a common type (any reason > they would not?). > > What is more, te-node-id is currently defined in ietf-te-types as 32-bit > only, whereas the references it mentions include 128-bit format; e.g. > RFC 6119 (section 3.2.1.) says: "it is useful to have a stable IPv6 > address identifying a TE node. The IPv6 TE Router ID TLV is defined in > Section 4.1." > Fixing te-types:te-node-id is a prerequisite to fully solve the 2nd > issue above. > > Thanks, > > Julien, et al.
- [Teas] Types within ietf-te-path-computation and … Julien Meuric
- Re: [Teas] Types within ietf-te-path-computation … Igor Bryskin
- Re: [Teas] Types within ietf-te-path-computation … Igor Bryskin
- Re: [Teas] Types within ietf-te-path-computation … Belotti, Sergio (Nokia - IT/Vimercate)
- Re: [Teas] Types within ietf-te-path-computation … Julien Meuric
- Re: [Teas] Types within ietf-te-path-computation … Igor Bryskin
- Re: [Teas] Types within ietf-te-path-computation … Belotti, Sergio (Nokia - IT/Vimercate)
- Re: [Teas] Types within ietf-te-path-computation … Igor Bryskin
- Re: [Teas] Types within ietf-te-path-computation … tom petch
- Re: [Teas] Types within ietf-te-path-computation … Igor Bryskin
- Re: [Teas] Types within ietf-te-path-computation … tom petch
- Re: [Teas] Types within ietf-te-path-computation … Igor Bryskin
- Re: [Teas] Types within ietf-te-path-computation … tom petch