[Netconf] schema capabilities in hello

Mikael Abrahamsson <swmike@swm.pp.se> Wed, 09 May 2018 06:14 UTC

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Date: Wed, 09 May 2018 08:14:44 +0200
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: netconf@ietf.org
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Subject: [Netconf] schema capabilities in hello
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Hi,

I received a question I couldn't answer. It was regarding capabilities 
exchange in hellos:

https://tools.ietf.org/html/rfc6241#section-8

It seems common way of doing this is to list all schemas as "capabilties". 
The person asking the question said one vendor did not list all schemas in 
capabilities, and one NMS they were trying out relied on the schemas being 
listed in the hello, for discovery.

Looking at above URL from the NETCONF RFC, one might imply that it only 
talks about netconf capabilities, not what schemas it supports. Yet, most 
implementations seem to list all schemas in their hellos.

So which one is correct here? My immediate reaction is that it's kind of 
"bloated" to list 1000 schemas (or more) in the hello, and that the 
schemas supported is something that shouldn't need to be exchanged every 
time one connects to the device.

Thoughts?

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se