[netconf] YANG encoding in CBOR

"Rob Wilton (rwilton)" <rwilton@cisco.com> Fri, 22 March 2019 12:42 UTC

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From: "Rob Wilton (rwilton)" <rwilton@cisco.com>
To: "core@ietf.org" <core@ietf.org>, "netconf@ietf.org" <netconf@ietf.org>
Thread-Topic: YANG encoding in CBOR
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Date: Fri, 22 Mar 2019 12:42:47 +0000
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Subject: [netconf] YANG encoding in CBOR
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As part of YANG evolution discussion, that was some talk about using a binary encoding of YANG in NETCONF or RESTCONF.

CBOR looks like a good fit for this, and obviously CORE WG are working on draft-ietf-core-yang-cbor-07, but one comment came up from Andy that the CBOR encoding of YANG cannot handle all YANG data models.  In particular, because of the way that the encoding works there are limitations on how unions of enums work.  Is that still the case?

Hence I was wondering whether it would be better to encode enum values in CBOR using module-qualified names, or also assign them SIDs and use the SIDs.  Has this approach been considered at all?

Or, is there an alternative approach to how we could/should consider using CBOR as a binary encoding for YANG data in NETCONF or RESTCONF?

Do you think it would be possible to get interested parties together to discuss this at some point in Prague?