On Fri, Mar 29, 2019 at 09:07:18AM -0700, Andy Bierman wrote: > On Fri, Mar 29, 2019 at 4:19 AM Juergen Schoenwaelder < > [email protected]> wrote: > > > Hi, > > > > this is issue is closed but I wonder whether this is correct. I have > > several questions looking at the issue on github: > > > > - Why is this not a YANG issue? > > - Which workaround is better? > > - Why is this tagged as a NETCONF issue? > > > > > Did you mean this should be NETCONF issue? > It is more of a protocol problem then a modeling problem. > The goal is to use the model unaltered. I think it would be valuable if say the definition of ipv4-address could state that a canonical binary representation is of type binary { length 4; }. Doing this is only meaningful for some types but it would allow to add more binary representations over time. > > If we want to support binary encodings, we need to allow modelers to > > define which types map to a canonical binary representation in > > addition to the canonical string representation. As stated in the > > issue description, hard-wiring some types in the encoding > > specifications is very limited. > > > > In terms of backwards compatibility, this issue should IMHO be tagged > > high (adding binary encoding for some types does not cause any > > backwards compatibility problem since so far we have only strings). > > > > > Not so sure. > The base64 encoding could look like a valid string. > The receiver must know a binary type is being sent (XML and JSON both fail > here, but not CBOR).
I am talking about CBOR, not about XML or JSON. I want to provide hints to CBOR (or similar binary encodings) that values can be represented in a different format. I do not expect these hints to be used by XML or JSON. If you need binary encoding efficiency, use CBOR instead of JSON. > > While I do not have a solution proposal, I think this issue is worth > > to look at and we should not close it right now. > > > > > I have a solution proposal, but I have not implemented it yet, so it it not > detailed... > > Both sender and receiver need to agree on the binary encoding and how the > data is tagged as binary. > > This expired draft should address that problem: > https://tools.ietf.org/html/draft-mahesh-netconf-binary-encoding-01 > > For every type T that they agree on, there are standard T.b2y() and T.y2b() > conversion functions. > There are also some extensions to define conversion templates so vendors > can add their own types. > > The YANG modules do not need to actually be altered. The peers will > negotiate the > set of types that will be sent as binary when the session starts. > The receiver knows T and the SID for each object, and will accept either > the YANG or binary encoding. Sounds complex for me to negotiate this. I rather say once that a binary encoding can ship an IPv6 address as type binary { length 16; } and then CBOR will simply do the right thing. /js -- Juergen Schoenwaelder Jacobs University Bremen gGmbH Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany Fax: +49 421 200 3103 <https://www.jacobs-university.de/> _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
