Re: [Teas] IETF TE Topology YANG Model Design Meeting Notes - 2016-05-23

[Igor Bryskin <[e-mail]>]

Hi Young,

Please, see in-line,

Igor

From: Leeyoung
Sent: Thursday, May 26, 2016 11:31 AM
To: Xufeng Liu; Vishnu Pavan Beeram; Igor Bryskin; Oscar Gonzalez De Dios; Tarek Saad; Himanshu Shah; Lou Berger; BRUNGARD, DEBORAH A (ATTLABS); Susan Hares; Zafar Ali (zali); Khaddam, Mazen (CCI-Atlanta); Tony Le; BELOTTI, SERGIO (SERGIO); Beller, Dieter (Dieter); Rajan Rao; Zhangxian (Xian); [e-mail]; Belotti, Sergio (Nokia - IT); Anurag Sharma
Cc: [e-mail]
Subject: RE: IETF TE Topology YANG Model Design Meeting Notes - 2016-05-23

Hi Xufeng,

Thanks for this update. Your notes are always very helpful to understand the latest progress of this draft.

I have a few questions on the potentially adding model for labels for the connectivity matrix.


1.      You said:


               For each label
               o exclusivity (true/false)

Do you mean this bitmap?


2.      Are you aware of label restrictions applied for the connectivity matrix other than WSON? If so, then this model addition makes sense; if not, then we can add the label model for the connectivity matrix in the WSON YANG model. If the extent to which label model addition is not really a major constraint in the switching technologies other than WSON, it would be worthwhile to evaluate if we should do label restriction model in a generic way (per this draft) or do it in WSON specific way?  I am not aware of any label restriction model for the connectivity matrix for GMPLS other than WSON.
IB>> We had this discussion many time already. There are physical OTN switches that have constraints on the ODUk type level. For example, a switch can switch ODU2 from link 1 to link2, but ODU2e from link 1 to only link3. This is especially true for abstract compound nodes which may represent entire network domains. As you know abstract TE modes are very important for this model. So, no, connectivity restriction on a label level does not apply only to WDM.



3.       If we were to extend the label model for the connectivity matrix, I would think we also need to have label restriction model for TTP LLCL as well. What do you think?
IB>> This is actually a good point. Thanks for pointing out.

Cheers,
Igor


Thanks.
Young


From: Teas [mailto:[e-mail]] On Behalf Of Xufeng Liu
Sent: Thursday, May 26, 2016 9:48 AM
To: Vishnu Pavan Beeram; Igor Bryskin; Oscar Gonzalez De Dios; Tarek Saad; Himanshu Shah; Lou Berger; BRUNGARD, DEBORAH A (ATTLABS); Susan Hares; Zafar Ali (zali); Khaddam, Mazen (CCI-Atlanta); Tony Le; BELOTTI, SERGIO (SERGIO); Beller, Dieter (Dieter); Rajan Rao; Zhangxian (Xian); [e-mail]; Belotti, Sergio (Nokia - IT); Anurag Sharma
Cc: [e-mail]
Subject: [Teas] IETF TE Topology YANG Model Design Meeting Notes - 2016-05-23

Participants:
Igor, Xufeng, Pavan, Dieter, Sergio, Himanshu

- Information sources
  > Discussed two use cases related to information sources:
    1) Provider applies policies to pick the most preferred.
    2) Provider does not apply policies and the decision is done by customer.
  > The model currently supports 1) well, but is not clear on 2).
  > Agreed to clarify the model by:
    1) Change "alt-information-sources" to "information-sources" to
       include all sources, including the selected one.
    2) For use case 1), the applied attribute has the selected value, and
       "information-sources" list all available sources.
       For use case 2), the applied attribute does not have value, and
       "information-sources" list all available sources.

- Connectivity Matrix
  > Discussed the comment from Cyril "to add a Label (Following
    RFC7579) restrictions".
  > Participants agreed that such constraint information is useful.
  > Participants agreed that such constraint information is generic
    enough to be used in various layers and use cases, including optical
    OTN, and abstract network topologies.
  > Participants agreed to send the suggestion TEAS WG to add such
    information to te-topology model.
  > The potential model change can be:
    For each connectivity-matrix entry, add:
      list of labels
        list types
               o inclusive-list
               o exclusive-list
               o inclusive-range
               o exclusive-range
               For each label
               o exclusivity (true/false)

Working members: please provide any comments.

Thanks,

- Xufeng

Note: Please drop me an email if you need an invite for joining the weekly call.

PS. Meeting on May 30 will be canceled for US holiday.