[Nmc-wg] [Fwd: Re: Netconf in pS]

[Arne Oslebo]

Hello,

I apologize for not replying to this earlier but I wanted to wait till 
the documentation that I had written was available.


Roman Lapacz wrote:
>
> -------- Original Message --------
> Subject:     Re: [Nmc-wg] Netconf in pS
> Date:     Thu, 21 Jan 2010 09:39:45 -0500
> From:     Jason Zurawski <zurawski at internet2.edu>
> Reply-To:     zurawski at internet2.edu
> Organization:     Internet2
> To:     Roman Lapacz <romradz at man.poznan.pl>
> CC:     nmc-wg at ogf.org <nmc-wg at ogf.org>
> References:     <4B5701F4.3060607 at man.poznan.pl>
>
>
>
> Hi Roman;
>
> Thanks for providing this, pretty neat.  Also for reference the NETCONF
> RFC is here:
>
> http://tools.ietf.org/html/rfc4741
>
>> I'm sending you some info about the investigation work (by Arne
>> Oslebo) on Netconf in pS which is being done in Geant3. After a while
>> I will add a detailed description from one of project documents but
>> it's still under review process so it must wait a bit.
>>
>> http://software.uninett.no/stager/wiki/netconf
>
> An obvious issue that the author has pointed out to not use NM-WG/NMC-WG
> is the lack of documentation both at a protocol and service level, which
> is a failing for the pS consortium in general.  Hopefully this will be
> rectified soon through this group.
There are actually three issues with NM-WG/NMC-WG that we point out:
* Lack of proper separation between information model and communication 
model.
* Lack of generic information model for MA and MP.
* Lack of proper validation mechanisms.

For more details please see the document that Roman sent to the list 
last week.

>
> To comment on the subject matter itself, I am having a hard time
> justifying in my mind why trying to use a protocol designed for a
> similar (but not identical) task is a good idea.  In NETCONF's own 
> words it:
>
>> provides mechanisms to install, manipulate, and delete the
>> configuration of network devices
>
> This touches a gray area in perfSONAR that has been the topic of DICE 
> meetings in the past, namely managing the service configuration vs the 
> measurement configuration. I think there may be a place in perfSONAR 
> for this protocol, but I don't believe that exchanging/storing the 
> actual data with the NETCONF primitives makes sense.
I know that the topic of what NETCONF can and can not be used for is a 
controversial topic, even within IETF. Things are however starting to 
change. For NETCONF to be used as a generic network management protocol 
it needs proper access control. I attended IETF this week and a private 
draft proposing an access control model for NETCONF was very well 
received in the NETCONF working group and it was decided that this is 
something that the working group will start to work on. So while IETF 
still has not made any official statement, people are now openly talking 
about NETCONF becoming the next preferred network management protocol 
instead of SNMP.

This is part of the motivation behind our work. We believe that 
perfSONAR basically is distributed network management in a multi domain 
setting. Looking at the data that is stored in the various MA and MP 
implementations we don't see any fundamental difference between this 
information and what you typically collect in normal network management. 
So if NETCONF can be used for normal network management, why can it not 
be used in perfSONAR? Our simple prototype shows that it can be used.
>
> I will end by noting a reply that Martin has been known to give in the 
> past: "its all just XML!".
I agree completely but would like to turn this argument around. Since 
there already exists XML protocols for transporting data from A to B, 
NETCONF being one of them, why spend so much time and effort defining 
yet another protocol? After all "its all just XML".
> Maybe we can see a demonstration at the next developers meeting to see 
> how valuable this could be.
We had I demo site up and running, but I see that it is now giving error 
messages. I will look at it next week and try to fix it.

I'm currently working on a more stable implementation that will also 
simplify the information model. The deadline for this work is in June 
but I hope to have it finished before that.

Best regards,
Arne