Re: [Detnet-dp-dt] quick notes from 1/31/17 call

[Jouni Korhonen <[e-mail]>]

Carlos,


> On 05 Feb 2017, at 03:56, Carlos Jesús Bernardos Cano <[e-mail]> wrote:
> 
> Hi Jouni, all,
> 
> Thanks for the minutes and apologies for not joining this time.
> 
> I have a couple of questions:
> 
> 1. For the transport, we have so far assumed MPLS and IP PSNs (focusing
> the discussion mainly on MPLS until this week). Are we restricted to
> only these two? I think in some use cases other transports such as
> MPLS-TP can be relevant as well. Will we explore this too/make the
> solution open enough to support other transports?

Most of the DetNet DP “sauce” is on the PW layer. We already assured that the PSN can be either a LSP or IP. Since MPLS-TP includes PWE is see no reason why “MPLS-based” PSN could not also be implemented using MPLS-TP.

> 2. How are organizing to work on the first draft text? I'm available to
> contribute text.

I’ll get the first round up soon. Then we can divide the job into sections that everybody (volunteering) is responsible for.

- Jouni



> 
> Thanks!
> 
> Carlos
> 
> On Wed, 2017-02-01 at 18:02 -0800, Jouni Korhonen wrote:
>> Present: Jouni, Loa, Norm, Balazs, Janos, Tal and David.
>> 
>> See the attached slideset that was used as the basis during the call.
>> The MPLS-based PWE encaps has matured, except for: 1) fine grained
>> CoS (i.e., 802.1 has discussed finer granularity of CoS basically to
>> a flow level. The flow identification mechanism in .1CB, .1Qci et al
>> allows this), and 2) PW CW SN width. We have discussed using 28 bits
>> but that might cause issues when interworking with systems that only
>> understand 16 bits (HSR and PRP as an examples). 
>> The CoS part and whether TC bits are copied between layers is still
>> to be discussed further.
>> IP PSN seems OK. The questions on the slides were discussed:
>> - PW labels are still good to have. It makes the stack/implementation
>> more streamlined between MPLS and IP PSNs. Also PW labels make PW
>> switching way easier e.g., in a case of replication/elimination.
>> - In a case of IP PSN each PW will have their own “tunnel” between T-
>> /S-PEs. That means e.g., a PW between A and B will have different
>> src/dst addresses than a PW between B and D. This makes pinned down
>> paths easier to realize using IP PSN.
>> 
>> Norm asks for the cases where DetNet interworks with e.g. 802.1TSN.
>> Would there be a way to regenerate MAC addresses if those are not
>> transported over DetNet (this is for the case where the L2 is just so
>> bug that interconnect does not make sense). Discussion.. Jouni
>> commented that it is not in current document’s scope. Could be worked
>> in parallel once the encaps for DetNet DP mature a bit.
>> 
>> Loa comments that EXP bits in an MPLS labels should use TC instead
>> (Traffic Class), see RFC5462.
>> 
>> Jouni commented that we now start to have enough material to produce
>> a draft of a draft. Expect the first version next week.
>> 
>> Quick discussion on 1588 PTP in DetNet. 1588 packets should not be
>> replicated. Actually using DetNet encapsulation for them is not
>> really a good idea. Tal will educate us more on that next time.
>> 
>> Action points:
>> Tal will produce a slideset regarding his thoughts/concerns on 1588
>> transport in DetNet.
>> 
>> Next call: 2/7/17 10PM PDT
>> 
>> 
>> --
>> Jouni Korhonen, Broadcom Ltd.
>> M: [phone]
>> 
>> _______________________________________________
>> Detnet-dp-dt mailing list
>> [e-mail]
>> https://www.ietf.org/mailman/listinfo/detnet-dp-dt