Tom, I hope you are aware of the work we are doing in the TEAS working group, which develops a YANG Abstract TE Topology model, which does support multi-layer TE topologies (both native and abstract/customized, both learned and configurable) with layer specific augmentations in the road map. We want this model to be part of the I2RS family, but we also want the model to be used outside of I2RS, for example, in the ACTN context.
We are also working on a multi-vendor interop event based on the model, which we hope to make happen within 2015. Cheers, Igor -----Original Message----- From: Nadeau Thomas [mailto:[email protected]] Sent: Thursday, July 02, 2015 8:55 AM To: Juergen Schoenwaelder Cc: Joel M. Halpern; b nitin; [email protected]; [email protected]; Hariharan Ananthakrishnan; [email protected]; [email protected]; Igor Bryskin; Linda Dunbar; Jan Medved (jmedved) Subject: Re: [i2rs] comments to draft-ietf-i2rs-yang-network-topo-01 > On Jul 2, 2015:2:51 AM, at 2:51 AM, Juergen Schoenwaelder > <[email protected]> wrote: > > True in principle but then there is apparently also confusion about > scope and relationship of the work to what is called an I2RS agent. That is for sure. > My proposal back then was to charter a short-lived WG to produce a > generic topology model so that this important piece of work is not > tied to any other WG with its specific scope. This proposal did not > fly but I still believe this would have been the cleanest approach. I would be all for this at this point. Pruning down the scope of topology to fit into the current I2RS box (which I disagree with) does not seem to be working out well in terms of the topo work at the IETF. Due to this mismatch, those interested in topology will find that outside projects such as ODL have progressed topology well beyond what is being discussed in i2rs. For example, multi-layered topology is a reality and there is a functional implementation of this. Maybe the solution is to indeed pull topology out of the i2rs WG and let it progress independently? > Anyway, good to read that topology people plan to get together in > Prague. Getting the right people to sit together is at the end what > makes work move ahead. For sure. —Tom > > /js > > On Wed, Jul 01, 2015 at 08:41:09AM -0400, Nadeau Thomas wrote: >> >> I personally think its important to do a generic topology model as well >> as provide a layered model. This is something that has and is implemented >> and deployed, so it is clearly important and useful. Where its done is >> nearly irrelevant just as long as it gets done. >> >> —Tom >> >> >>> On Jun 30, 2015:1:41 AM, at 1:41 AM, Juergen Schoenwaelder >>> <[email protected]> wrote: >>> >>> I have been in the same boat but some people thought it is really >>> important to do a generic topology model in I2RS so here we go. >>> >>> /js >>> >>> On Mon, Jun 29, 2015 at 05:06:17PM -0400, Joel M. Halpern wrote: >>>> You may recall that I have expressed concern about many times about >>>> how the network topology draft fits the I2RS scope. It is still >>>> not clear to me that it is an I2RS item, although it is clearly >>>> useful for things talking to the I2RS Agent. >>>> >>>> Yours, >>>> Joel >>>> >>>> On 6/29/15 5:01 PM, Linda Dunbar wrote: >>>>> Joel, Igor, Juergen, >>>>> >>>>> Thanks for the feedback. Actually I always thought I2RS Agent is >>>>> within a single routing engine until reading the "I2RS Topology" draft. >>>>> >>>>> I see draft-ietf-i2rs-rib-info-model-06 as a very clear and good >>>>> specification for information exchange between a routing engine >>>>> and its client. It reflects one single node's RIBs associated with >>>>> multiple Routing Instances supported by the routing engine. >>>>> >>>>> But the "I2RS Topology", which is also a very good specification >>>>> describing the network view of topologies (which consists of >>>>> multiple nodes and links among them), is more suited for the >>>>> entity that manages multiple routing nodes. >>>>> >>>>> RIBs of one routing engine and "topology of multiple routing engines" >>>>> definitely represent different perspectives: one is node view, >>>>> another one is the network view. >>>>> >>>>> >>>>> In order to make I2RS widely adopted by the industry, it is very >>>>> important not to make it too complicated. Routing is not simple to >>>>> start with, therefore, it becomes especially more important to >>>>> keep I2RS specification simple and to the point. >>>>> >>>>> Therefore, I suggest to have a paragraph in the "network-topo" >>>>> draft to describe that this is for the network view, it is for >>>>> clients who manage/monitor multiple routing engines. >>>>> >>>>> My two cents. >>>>> >>>>> Linda >>>>> >>>>> -----Original Message----- >>>>> From: Igor Bryskin [mailto:[email protected]] >>>>> Sent: Monday, June 29, 2015 1:33 PM >>>>> To: Joel M. Halpern; Linda Dunbar; Juergen Schoenwaelder >>>>> Cc: [email protected]; '[email protected]'; [email protected]; >>>>> Hariharan Ananthakrishnan; [email protected]; [email protected]; Jan >>>>> Medved (jmedved) >>>>> Subject: RE: [i2rs] comments to >>>>> draft-ietf-i2rs-yang-network-topo-01 >>>>> >>>>> I agree with Joel, >>>>> >>>>> To answer Linda's question: if I2RS agent manages/represnts >>>>> multiple physical devices, the interface between the agent and the >>>>> devices is out of scope of I2RS. Note that such interface needs to >>>>> be standardized only if one considers a scenario where an I2RS >>>>> agent controls devices from different vendors. IMHO this scenario >>>>> is unlikely, and at least for now it is safe to assume that said >>>>> interface is private. >>>>> >>>>> Cheers, >>>>> Igor >>>>> >>>>> -----Original Message----- >>>>> From: i2rs [mailto:[email protected]] On Behalf Of Joel M. >>>>> Halpern >>>>> Sent: Monday, June 29, 2015 2:01 PM >>>>> To: Linda Dunbar; Juergen Schoenwaelder >>>>> Cc: [email protected]; '[email protected]'; [email protected]; >>>>> Hariharan Ananthakrishnan; [email protected]; [email protected]; Jan >>>>> Medved (jmedved) >>>>> Subject: Re: [i2rs] comments to >>>>> draft-ietf-i2rs-yang-network-topo-01 >>>>> >>>>> Juergen is correct that by the I2RS definition an I2RS Agent is >>>>> part of, and associated with, a single routing element. >>>>> >>>>> It is true that the routing element may itself be a controller >>>>> supporting and interacting with multiple forwarding elements. >>>>> That is not required, and not discussed, by I2RS. As far as I2RS >>>>> is concerned, the multiplicity is that the relationship between I2RS >>>>> Clittns and I2rS agents is N:M. >>>>> That is, a client may be working with multiple agents, >>>>> and an agent may be communicating with multiple clients. But it is >>>>> still the case that the agent is collocated with the routing >>>>> system, and is not in a separate controller from the routing system. >>>>> >>>>> Yours, >>>>> Joel >>>>> >>>>> On 6/29/15 10:46 AM, Linda Dunbar wrote: >>>>>> Juergen, >>>>>> >>>>>> One I2RS agent can interface with multiple routing elements. >>>>>> >>>>>> The network view (which consists of multiple nodes, i.e. >>>>>> topology) has to be over multiple nodes. Therefore, it is the >>>>>> interface between client and Agent. Whereas, there are commands to >>>>>> individual routing element. >>>>>> >>>>>> Linda >>>>>> -----Original Message----- >>>>>> From: Juergen Schoenwaelder >>>>>> [mailto:[email protected]] >>>>>> Sent: Monday, June 29, 2015 3:28 AM >>>>>> To: Linda Dunbar >>>>>> Cc: '[email protected]'; [email protected]; Jan Medved (jmedved); >>>>>> [email protected]; [email protected]; Hariharan >>>>>> Ananthakrishnan; [email protected] >>>>>> Subject: Re: [i2rs] comments to >>>>>> draft-ietf-i2rs-yang-network-topo-01 >>>>>> >>>>>> Linda, >>>>>> >>>>>> according to draft-ietf-i2rs-architecture-09, an I2RS agent is >>>>>> part of a routing element. I am not sure your understanding "I2RS >>>>>> Agent is like the SDN controller" is consistent with the architecture >>>>>> document. >>>>>> >>>>>> /js >>>>>> >>>>>> On Fri, Jun 26, 2015 at 05:03:25PM +0000, Linda Dunbar wrote: >>>>>>> Alex, et al, >>>>>>> >>>>>>> The I2RS architecture depicts two types of interfaces: >>>>>>> >>>>>>> - One is the interface between Agent and Client, and >>>>>>> >>>>>>> - another is the interface between Agent and Routing entities. >>>>>>> >>>>>>> >>>>>>> The network model and inventory are more for the interface >>>>>>> between Agent and the Clients, isn't it? One single routing >>>>>>> engine doesn't need to know the overall topology and inventory >>>>>>> information of other nodes, even though some may do. >>>>>>> >>>>>>> >>>>>>> And the /nd:network/nd:node and Termination points are more for >>>>>>> the interface between the Agent and the Forwarding Engine, isn't it? >>>>>>> >>>>>>> IMHO, the information models should be oriented around the I2RS >>>>>>> architecture. I.e. with description on where those information >>>>>>> models are applicable, making it easier to differentiate from >>>>>>> other IETF WGs work (such as L2VPN, L3VPN, or SFC). I recall >>>>>>> there were some debates at the Dallas I2RS session. >>>>>>> >>>>>>> I2RS Agent is like the SDN controller, which can inform clients >>>>>>> about the topology information, instruct routes to routing >>>>>>> engine of multiple nodes, and retrieve link & termination points >>>>>>> status from each of those nodes. >>>>>>> >>>>>>> The "Service Overlay" in Section 3.4.8 is definitely meant for >>>>>>> clients not towards individual nodes. Mixing them all together make it >>>>>>> confusing. >>>>>>> >>>>>>> Cheers, >>>>>>> >>>>>>> Linda Dunbar >>>>>>> >>>>>>> >>>>>> >>>>>>> _______________________________________________ >>>>>>> i2rs mailing list >>>>>>> [email protected] >>>>>>> https://www.ietf.org/mailman/listinfo/i2rs >>>>>> >>>>>> >>>>> >>>>> _______________________________________________ >>>>> i2rs mailing list >>>>> [email protected] >>>>> https://www.ietf.org/mailman/listinfo/i2rs >>>>> >>> >>> -- >>> Juergen Schoenwaelder Jacobs University Bremen gGmbH >>> Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany >>> Fax: +49 421 200 3103 <http://www.jacobs-university.de/> >>> >>> _______________________________________________ >>> i2rs mailing list >>> [email protected] >>> https://www.ietf.org/mailman/listinfo/i2rs >> > > -- > Juergen Schoenwaelder Jacobs University Bremen gGmbH > Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany > Fax: +49 421 200 3103 <http://www.jacobs-university.de/> _______________________________________________ i2rs mailing list [email protected] https://www.ietf.org/mailman/listinfo/i2rs
