Re: [OPSAWG] Negotiation replacing configuration

Hi Anoop, thanks for the comments. Answers in line.

On 31/01/2014 16:18, Anoop Ghanwani wrote:
> Brian,
> 
> Many protocols already do some type of negotiation but it is based on
> capabilities and local/remote configuration rather than operational state
> -- at the link layer 802.3x and DCBX come to mind, with routing protocols
> operational parameters such as the hello timer come to mind, or even with
> TCP things like ECN and SACK are negotiated.  But that is a one-off
> negotiation at startup.

Yes, and we'd like more examples of existing negotiations.

> The draft seems to want to take this kind of negotiation one step further.
>  It looks like an interesting concept.  I worry a bit about the complexity.

Well, our hope is that the protocol itself would be rather simple.
But like "Simple" Network Management Protocol, the solutions constructed
with the protocol would be rather complex. The point is that humans
wouldn't have to deal with the complexity.

>  This also seems to be moving in the opposite direction of a centralized
> SDN controller making global decisions and implementing them (just an
> observation, not a judgement about whether it's a good or bad thing). 

Absolutely correct. It has been pointed out that SDN controllers
don't have to be literally central and global, but if you have multiple
controllers you'd need some kind of arbitration between them; in our
minds that would be an application of generic negotiation, using
negotiation objectives that mean something to an SDN controller.

> It
> would help to see a detailed example of how this would actually work for a
> sample network/application for folks to get a feel for the complexity.

Agreed. Working out some detailed use cases is necessary, but it's
hard to do with assuming something about the actual protocol
We do have a draft about the protocol solution too, but it seems
better to start by discussing the problem.

Regards
    Brian

> Anoop
> 
> 
> On Tue, Jan 28, 2014 at 4:04 PM, Brian E Carpenter <
> brian.e.carpenter@gmail.com> wrote:
> 
>> Hi,
>>
>> I'm a bit surprised at the silence on this. After all, we
>> are suggesting a fairly radical change of approach: from
>> centrally-driven configuration of devices to peer negotiation
>> between devices. In this WG we'd like to get feedback on
>> the problem statement based on real experience, since the
>> NMRG discussion is more likely to be theoretical.
>> Also, is our summary of existing protocols accurate?
>>
>>     Brian
>>
>> -------- Original Message --------
>> Subject: I-D Action: draft-jiang-config-negotiation-ps-02.txt
>> Date: Sat, 18 Jan 2014 11:23:25 -0800
>> From: internet-drafts@ietf.org
>> Reply-To: internet-drafts@ietf.org
>> To: i-d-announce@ietf.org
>>
>>
>> A New Internet-Draft is available from the on-line Internet-Drafts
>> directories.
>>
>>
>>         Title           : Network Configuration Negotiation Problem
>> Statement and Requirements
>>         Authors         : Sheng Jiang
>>                           Yuanbin Yin
>>                           Brian Carpenter
>>         Filename        : draft-jiang-config-negotiation-ps-02.txt
>>         Pages           : 14
>>         Date            : 2014-01-18
>>
>> Abstract:
>>    This document describes a problem statement and general requirements
>>    for distributed autonomous configuration of multiple aspects of
>>    networks, in particular carrier networks.  The basic model is that
>>    network elements need to negotiate configuration settings with each
>>    other to meet overall goals.  The document describes a generic
>>    negotiation behavior model.  The document also reviews whether
>>    existing management and configuration protocols may be suitable for
>>    autonomic networks.
>>
>>
>> The IETF datatracker status page for this draft is:
>> https://datatracker.ietf.org/doc/draft-jiang-config-negotiation-ps/
>>
>> There's also a htmlized version available at:
>> http://tools.ietf.org/html/draft-jiang-config-negotiation-ps-02
>>
>> A diff from the previous version is available at:
>> http://www.ietf.org/rfcdiff?url2=draft-jiang-config-negotiation-ps-02
>>
>>
>> Please note that it may take a couple of minutes from the time of
>> submission
>> until the htmlized version and diff are available at tools.ietf.org.
>>
>> Internet-Drafts are also available by anonymous FTP at:
>> ftp://ftp.ietf.org/internet-drafts/
>>
>> _______________________________________________
>> I-D-Announce mailing list
>> I-D-Announce@ietf.org
>> https://www.ietf.org/mailman/listinfo/i-d-announce
>> Internet-Draft directories: http://www.ietf.org/shadow.html
>> or ftp://ftp.ietf.org/ietf/1shadow-sites.txt
>>
>>
>> --
>> Regards
>>    Brian Carpenter
>>    http://orcid.org/0000-0001-7924-6182
>>
>>
>>
>> _______________________________________________
>> OPSAWG mailing list
>> OPSAWG@ietf.org
>> https://www.ietf.org/mailman/listinfo/opsawg
>>
> 