Hi Greg,

From: Greg Mirsky <[email protected]<mailto:[email protected]>>
Date: Monday, June 5, 2017 at 8:43 PM
To: Acee Lindem <[email protected]<mailto:[email protected]>>
Cc: 
"[email protected]<mailto:[email protected]>"
 
<[email protected]<mailto:[email protected]>>,
 
"[email protected]<mailto:[email protected]>"
 
<[email protected]<mailto:[email protected]>>,
 Routing WG <[email protected]<mailto:[email protected]>>, 
"[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>>
Subject: Re: MPLS label and LSE data models

Hi Acee,
I think rather of the contrary, Static MPLS LSP must include TC and TTL. And 
Bottom-of-the-stack flag as well (I don't see it in grouping mpls-label-stack 
of the ietf-routing-types).

I just looked at a couple implementations and they do not include per-label 
provisioning of the traffic class and TTL. One would certainly NOT want to 
provision bottom of stack. Even if you put it in the rightmost label, other 
routes which are already labeled could resolve over the static LSP.

As far as adding a separate leaf list for the mpls-label type, I don’t think 
this is necessary as adding a type just to abstract a YANG list just adds 
complexity.

Anyway, I’m deferring to the authors of the MPLS static model if they desire 
any additional types in ietf-routing-types.

Thanks,
Acee


Regards,
Greg

On Mon, Jun 5, 2017 at 4:55 PM, Acee Lindem (acee) 
<[email protected]<mailto:[email protected]>> wrote:
Greg, et al,

From: Greg Mirsky <[email protected]<mailto:[email protected]>>
Date: Monday, June 5, 2017 at 6:28 PM
To: 
"[email protected]<mailto:[email protected]>"
 
<[email protected]<mailto:[email protected]>>,
 
"[email protected]<mailto:[email protected]>"
 
<[email protected]<mailto:[email protected]>>
Cc: Routing WG <[email protected]<mailto:[email protected]>>, 
"[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>>
Subject: MPLS label and LSE data models
Resent-From: <[email protected]<mailto:[email protected]>>
Resent-To: Yingzhen Qu <[email protected]<mailto:[email protected]>>, 
<[email protected]<mailto:[email protected]>>, Acee Lindem 
<[email protected]<mailto:[email protected]>>, Christian Hopps 
<[email protected]<mailto:[email protected]>>, 
<[email protected]<mailto:[email protected]>>
Resent-Date: Monday, June 5, 2017 at 6:28 PM

Dear Authors, et.al<http://et.al>,
I've got a question, or several of them, about data models of MPLS label and 
MPLS label stack element (LSE). I ahve not followed the discussions and 
apologize if these already were considered, discussed.
In the Routing Types document I've found that only MPLS label being modeled but 
not the MPLS LSE. As result, models that use rt-types:mpls-label, e.g. YANG 
DAta Model for MPLS Static LSPs, defines outgoing labels not as array of LSEs 
but as array (leaf-list) of MPLS labels. In the latter document I don't see how 
TTL and Traffic Class (TC) are presented for each of labels in the array. Hence 
my questions:

  *   should there be data model of MPLS LSE in rt-types (it does have TTL and 
TC but separately);

  *   should data model of Static MPLS LSP use MPLS LSE model rather than model 
of only 20 bit-long label.

Where else so you see  a requirement for a label stack with entries that don’t 
contain TC and TTL? This seems specific to static provisioning of static LSPs 
rather than a general requirement for ietf-routing-types.

Thanks,
Acee


Appreciate you comments.

Regards,
Greg

_______________________________________________
rtgwg mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/rtgwg

Reply via email to