Subject: [Pce] Charter and Multi-Domain

From: <[email-masked]>
Date: Tue, 3 Nov 2009 17:48:35 +0100

Hi PCE members.

As you may (SHOULD ;-) ) have noticed in our agenda for Hiroshima, Daniel King will present his I-D named "The Application of the PCE Architecture to the Determination of a Sequence of Domains in MPLS & GMPLS" (introduced during the Stockholm meeting). Nonetheless our current charter soberly says:
"The PCE WG will work on application of this model within a single Domain
or within a small group of domains (where a domain is a layer, IGP area
or Autonomous System with limited visibility from the head-end LSR). At
this time, applying this model to large groups of domains such as the
Internet is not thought to be possible, and the PCE WG will not spend
energy on that topic."

In other words, we are flirting with our charter border and the scope of some drafts depends on it. In this context, the chairs would like to get a feedback from the WG on evolving towards larger groups of domains.
Does the WG think we are now ready to follow this path? Do you have operational requirements and/or concerns in mind in terms of applicability, order of magnitude, implementation...? Comments are very welcome.

You are probably aware that we have passed over a milestone about rechartering: beyond the upcoming meeting, your feedback will be useful input for the envisioned charter update (targetted for the end of the year).

Many thanks

JP & Julien

---

From: "Daniel King" <[email-masked]>
Date: Tue, 3 Nov 2009 20:08:39 -0000

Hi Julien, all. 

Good topic. 

When we starting to work on the H-PCE architecture
(draft-king-pce-hierarchy-fwk-xx) it was in response to perceived scaling
concerns of BRPC, if the sequence of domains was not pre-defined. Our view
is that solving the domain routing problem for as few as six interconnected
domains could be really hard if BRPC is used without a pre-defined domain
sequence.  

So, I think our I-D is within the current WG charter. I'd actually go a step
further and say that our I-D is not aimed at a larger set of domains at this
stage. 

Lastly, I do welcome the WG discussing extending the scope of the charter.
Perhaps it may be worth defining what we mean by a "larger groups of
domains", it's certainly >2 and <Internet. Would up to 20 domains be a good
reference point when defining/discussing a large group of domains? 

Br, Dan. 
 
-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of
[email-masked]
Sent: 03 November 2009 16:49
To: [email-masked]
Subject: [Pce] Charter and Multi-Domain

Hi PCE members.

As you may (SHOULD ;-) ) have noticed in our agenda for Hiroshima, Daniel
King will present his I-D named "The Application of the PCE Architecture to
the Determination of a Sequence of Domains in MPLS & GMPLS" (introduced
during the Stockholm meeting). Nonetheless our current charter soberly says:
"The PCE WG will work on application of this model within a single Domain
or within a small group of domains (where a domain is a layer, IGP area
or Autonomous System with limited visibility from the head-end LSR). At
this time, applying this model to large groups of domains such as the
Internet is not thought to be possible, and the PCE WG will not spend
energy on that topic."

In other words, we are flirting with our charter border and the scope of
some drafts depends on it. In this context, the chairs would like to get a
feedback from the WG on evolving towards larger groups of domains.
Does the WG think we are now ready to follow this path? Do you have
operational requirements and/or concerns in mind in terms of applicability,
order of magnitude, implementation...? Comments are very welcome.

You are probably aware that we have passed over a milestone about
rechartering: beyond the upcoming meeting, your feedback will be useful
input for the envisioned charter update (targetted for the end of the year).

Many thanks

JP & Julien
_______________________________________________
Pce mailing list
[email-masked]
https://www.ietf.org/mailman/listinfo/pce

---

From: JP Vasseur <[email-masked]>
Date: Sun, 8 Nov 2009 21:19:33 +0100

Hi Dan,

*co-chair hat off*

> domains could be really hard if BRPC is used without a pre-defined  

Two comments:
1) I personally think that the proposed mechanism is technically *good*
2) That being said, this raises the question on whether we need such  
mechanism considering
the relatively small scale of current deployments and I would welcome  
any evidence of lack of
scalability of BRPC in small scale network deployments.

> reference point when defining/discussing a large group of domains?

Well, as Adrian knows, I definitely do not like specifying hard  
numbers when it comes to defining
IP technologies since I do believe that one of the reasons of the  
success of the IP is precisely because
no numbers were specified in the original specifications. But yes 20  
seems a good reference point.

Cheers.

JP.

---

From: Meral Shirazipour <[email-masked]>
Date: Thu, 12 Nov 2009 15:29:09 -0500

Hello,
   I am with Daniel and JP regarding the need to start considering 
multiple domains and serious scalability pitfalls that might occur.   
Just a comment regarding setting numbers: although 20 domains would be 
a good start for testing some of  the different ID?s and proposals, I 
think it would be best to keep in mind that any solution should scale 
to other numbers >20. If a proposal is not scalable, at least provide 
the mechanism to deal with the situation: for example by detecting the 
problem (monitoring flooding, waiting times etc) and reporting back 
with notification error etc.).     To this end I propose adding a 
Scalability Section to all the upcoming IDs.
Regards,
Meral

"[email-masked]" <[email-masked]> a 
Ã©critÂ :

> Hi PCE members.
>
> As you may (SHOULD ;-) ) have noticed in our agenda for Hiroshima, 
> Daniel King will present his I-D named "The Application of the PCE 
> Architecture to the Determination of a Sequence of Domains in MPLS & 
> GMPLS" (introduced during the Stockholm meeting). Nonetheless our 
> current charter soberly says:
> In other words, we are flirting with our charter border and the scope 
> of some drafts depends on it. In this context, the chairs would like 
> to get a feedback from the WG on evolving towards larger groups of 
> domains.
> operational requirements and/or concerns in mind in terms of 
> applicability, order of magnitude, implementation...? Comments are 
> very welcome.
>
> rechartering: beyond the upcoming meeting, your feedback will be 
> useful input for the envisioned charter update (targetted for the end 
> of the year).
>
> Many thanks
>
> JP & Julien

---

From: "Adrian Farrel" <[email-masked]>
Date: Wed, 25 Nov 2009 13:02:21 -0000

Hi Meral,

Please be aware of the limitations of the current PCE charter. If the WG 
wants to go beyond the constraint of a "small group of domains" then it will 
need to recharter. As JP and Julien indicated, such an attempt to recharter 
needs to be accompanied by a discussion of the operational requirements 
and/or concerns in terms of applicability, order of magnitude, 
implementation...

That said, it is certainly worthwhile to add scalability considerations to 
I-Ds. The authors of draft-king-hierarchy-fwk intend to do some analysis of 
the use of BRPC in a small domain mesh when the domain sequence is not known 
in advance (and must be determined using BRPC).

Cheers,
Adrian

----- Original Message ----- 
From: "Meral Shirazipour" <[email-masked]>
To: <[email-masked]>
Cc: <[email-masked]>
Sent: Thursday, November 12, 2009 8:29 PM
Subject: Re: [Pce] Charter and Multi-Domain

Hello,

Ã©critÂ :

> King will present his I-D named "The Application of the PCE Architecture 
> to the Determination of a Sequence of Domains in MPLS & GMPLS" (introduced 
> applicability, order of magnitude, implementation...? Comments are very 
> welcome.
>