Re: [Pce] Whither Stateless PCE?

[Julien Meuric <[e-mail]>]

Hi Adrian,

Based on the evolution of this thread, it looks like it leaves us with 
the following guidelines:
- The case by case basis looks reasonable and should prevail;
- Extensions should focus on what is (eventually) useful;
- The scope of each work should be explicitly mentioned in I-Ds.

I hope this is an acceptable answer to your question.

Regards,

Julien


Apr. 07, 2016 - [e-mail]:
> > I think you are probably right, Dhruv. > > > > But referencing the 
ways in which customers deploy may be a little > limiting. > > To say 
PCE is widely deployed (even after all these years) may be an > 
exaggeration. > > Although we do have some clues about what is currently 
being pushed > for deployment. > > > > I think you have mainly grasped 
my point, however. We need to > understand which extensions are 
definitely only needed in one mode or > another, and which should be 
done in all modes (either because they > are needed or because we don't 
know). > > > > OTOH, I suppose TLVs are just TLVs. Once you specified 
the TLV it is > not rocket science to include it in a message. In fact, 
it is > probably one line of text to include it and only a short 
paragraph to > describe additional processing in other modes once you 
have described > how it is used in one mode. > > > > Where does that 
leave us? > > > > Adrian > > > > *From:*[e-mail] 
[mailto:[e-mail]] *On Behalf > Of *Dhruv Dhody *Sent:* 06 
April 2016 23:07 > > > > Hi Adrian, > > > > Even in the brave new world 
of Stateful PCE, PCReq and PCRep messages > do play a role in the 
passive stateful PCE mode. PCReq/PCRep also > play a crucial role in the 
inter-domain and inter-layer context in > the new proposal like stateful 
H-PCE. > > > > At the same time mandating that every extension (say SFC) 
must also > be specified in a stateless manner when no customer deploy 
in such a > way, might be overkill. > > > > Perhaps we need to look at 
it case by case! > > > > Dhruv > > > > On Wed, Apr 6, 2016 at 4:00 PM, 
Adrian Farrel <[e-mail] > <mailto:[e-mail]>> 
wrote: > > Once upon a time, in a working group far, far away, PCE was 
basically > stateless. PCE acted in response to questions asked by PCCs. 
 > > These days, everyone is excited by stateful PCEs and there is a lot 
 > of initiation (of LSPs or of control of LSPs). > > In the jabber room 
during today's meeting Ravi noted that not a lot > of the new drafts 
(maybe none of them) talk about PCReq messages. > This raises the 
question in our minds as to whether stateless PCE is > obsolete. > > If 
(and only if) this mode of PCE usage has gone out of fashion, we > 
*might* consider cleaning up the protocol and architecture so that we > 
don't need to make protocol extensions to PCReq and PCRep messages > 
when we make extensions to PCInit messages. > > Thoughts? > > Adrian >