Hi Tim,

Please see in-line.

Thanks,
Siva


From: spring <[email protected]> On Behalf Of Yu Tianpeng
Sent: Wednesday, November 14, 2018 3:06 AM
To: [email protected]
Subject: [spring] draft-ietf-spring-segment-routing-policy

Dear authors,
I have read the document and have some comments as below, hope will help.


2.1<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-2.1>.
  Identification of an SR Policy

[Tim]: I suggest we define a default color value 0x00000000 as “default 
behavior” or “best effort”. This value will help further interoperability 
between vendors. The other values are left user-defined.

Or we can say if the color is not specified, we should use 0x00000000 as 
default one. Also, I suggest we mention the higher value is, the higher SLA it 
indicates.

 <SIVA> Such a restriction is unnecessary. Color and end-point define an SR 
policy, and traffic steering mechanism (local behavior) at head-end dictates 
how a given SR policy is used to transport service.

2.12<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-2.12>.
  Priority of an SR Policy

[Tim]: Suggest to change the title to Re-compute priority to avoid confusing 
with preference defined previously.

 <SIVA> We shall consider this suggestion in the next  revision.

2.13<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-2.13>.
  Summary

[Tim]: Priority defined in 2.12 is not listed in the example.

 <SIVA> Noted.

In addition, a Segment-List MAY be declared invalid when:

[Tim]: Another case is: Its last label is not explicit-null neither. If I 
understand correctly, the logic of the two criteria is “AND” instead of “OR” 
right? I suggest we mention the logic here.

 <SIVA> We will add more clarity w.r.t explicit-null in the next revision, and 
yes logic is “OR”.

2.9<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-2.9>.
  Active Candidate Path

[Tim] [I-D.filsfils-spring-sr-policy-considerations] The reference link of this 
part does not work.

 <SIVA> Thanks for catching it. We will fix it.

6.2.1<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-6.2..1>.
  Frequent use-case: unspecified BSID

[Tim]: Suggest we change the title to “SR Policy specified BSID”

The BSID of all candidate paths are empty in such case, I don’t think we should 
use the word “unspecified BSID” which looks like a reserved BSID.

 <SIVA> I fail to understand the confusion. The text is also explanatory.



6.2.3<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-6.2.3>.
  Specified-BSID-only

[Tim]: An implementation MAY support the configuration of the 
Specified-BSID-only restrictive behavior on the headend for all SR Policies or 
individual SR Policies.

<SIVA> The text refers to applying restrictive behavior for some or all SR 
policies on a head-end.

It should be as below right?

An implementation MAY support the configuration of the Specified-BSID-only 
restrictive behavior on the headend for all SR candidate paths or individual SR 
candidate paths.



8.6<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-8.6>.
  Per-Flow Steering

[Tim]: I have concerns that BSID is programmed into the forwarding plane as in 
“6.2<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-policy-02#section-6.2>.
  BSID of an SR Policy” it is mentioned that “the BSID SHOULD NOT be used as an 
identification of an SR Policy.”

I suppose we at least mention if we use per-flow steering, we should not use 
Specified-BSID-only which lead to inpersistent BSID.
<SIVA> The point since BSID for an SR policy may change, it cannot be used a 
unique identifier of an SR policy.

Thanks..
Regards,
Tim

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

Reply via email to