Thanks for the reply. No other BBF specs (that I am aware of) require such restrictions. I (personally) think that handling this as a device requirement is a fine solution, but we wanted to check what people thought of trying to define such restrictions in the YANG.
BTW, we were thinking of: maximum length (64) and restricted character set (ASCII 32-126). William > On 11 Feb 2016, at 13:55, Juergen Schoenwaelder > <[email protected]> wrote: > > On Thu, Feb 11, 2016 at 12:22:19PM +0000, William Lupton wrote: >> All, >> >> Here in the Broadband Forum we are defining YANG modules that augment RFC >> 7223 ietf-interfaces. We want to limit interface name maximum length and >> character set but don't see a way of doing this in the YANG. >> >> Can/should we do do this in the YANG, or should it just be a device-level >> requirement? >> > > I wonder why you want to do this. Is it because other existing BBF > specifications break if interfaces can have long names and use Unicode > characters? Out of curiosity, what would be the length and character > set restriction BBF finds a good choice? > > A deviation statement describes how an implementation deviates from a > data model. It was not the intent that an SDO defines a 'standard' > deviation for a data model (the term 'profile' might be more > appropriate for this). > > Note that these kind of 'profiles' often do not combine well. If BBF > says the max length is N and MEF says that max length is N with N != > M, then an implementor has a hard time to produce a device that > satisfies both requirements. (All one can do is to use min(N,M) and > then annouce a deviation to the profiles affected, all getting pretty > ugly soon, in particular if the common native interface names may be > longer than N and M.) > > I understand that 'arbitrarily long' may sound ridiculous. But having > an implementation announce its real limit instead of a data model or > 'profile' imposed limit seems simpler and more robust to me. > > /js > > PS: On Windows, MAX_ADAPTER_NAME_LENGTH seems to be 256, on Linux > IF_NAMESIZE seems to be 16, on FreeBSD and MacOS IF_NAMESIZE seems > to be 16 as well (but there are likely systems derived from > FreeBSD that use a different constant, may also be true for Linux > - and most likely people change this constant for a reason). > > -- > Juergen Schoenwaelder Jacobs University Bremen gGmbH > Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany > Fax: +49 421 200 3103 <http://www.jacobs-university.de/> > _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
