Re: [Cbor] Supporting IPv6 Link-Local with scope (was Re: Éric Vyncke's Discuss on draft-ietf-cbor-network-addresses-09: (with DISCUSS and COMMENT))

Hi Rob,

thank you very much for the quick feedback!

I addressed the comments together with the IPv4 zone identifier discussion in
https://github.com/cbor-wg/cbor-network-address/pull/13

> On 2021-10-07, at 12:00, Rob Wilton (rwilton) <rwilton=40cisco.com@dmarc.ietf.org> wrote:
> 
> Hi Michael,
> 
> A couple of comments on -10
> 
> In section 2:
> - It still references a two element array for IP address and prefix, but presumably it is a 2 or 3 element array.

I added text that explains that case.

> - How often are zones actually used?  Would it not just be simpler to always use a string interface identifier?

Ifindex and Ifname are two different concepts that should not be mixed.
The textual nature of RFC 6991 makes it seem natural to always use a textual representation for the Ifindex; this is not the case here.

> - Is "false" for a prefix length a better choice than using either -1 or null?

false is not better than null.
Actually, as this is representing what would be an optional element in an array, conventional CBOR idioms would call for null, but that is a matter of style.
I switched to null in the PR because you brought it up, but don’t have a strong opinion.

false/null definitely is better than -1.

> I still think the example in section 4 probably needs fixing:
> 
>   52([44, h'20010db81230'])
> 
> ^- Should this be 54 rather than 52?

Fixed.

>   even though variations like:
> 
>   54([44, h'20010db81233'])
>   54([45, h'20010db8123f'])
> 
> ^- Should this be 44 rather than 45?  Because otherwise it looks like it would parse to a different prefix.

The example itself is good but the text around it doesn’t fit.  
Changed to 44.

Grüße, Carsten

> 
> Thanks,
> Rob
> 
> 
> -----Original Message-----
> From: iesg <iesg-bounces@ietf.org> On Behalf Of Michael Richardson
> Sent: 06 October 2021 17:19
> To: Eric Vyncke (evyncke) <evyncke@cisco.com>; cbor@ietf.org; draft-ietf-cbor-network-addresses@ietf.org; The IESG <iesg@ietf.org>; d3e3e3@gmail.com; barryleiba@computer.org; cbor-chairs@ietf.org; Brian E Carpenter <brian.e.carpenter@gmail.com>
> Subject: Re: Re: [Cbor] Supporting IPv6 Link-Local with scope (was Re: Éric Vyncke's Discuss on draft-ietf-cbor-network-addresses-09: (with DISCUSS and COMMENT))
> 
> 
> Hi, at the CBOR WG meeting this morning, support for IPv6 LL scopes
> was the major topic.
> 
> We added an optional third parameter to the interface definition,
> and made it valid to specify the interface prefix length as "false"
> 
> I hope that I got the CDDL right:
>  https://github.com/cbor-wg/cbor-network-address/blob/main/cbor-network-addresses.mkd#cddl
> 
> Examples:
>  https://github.com/cbor-wg/cbor-network-address/blob/main/cbor-network-addresses.mkd#ipv6
> 
> We also agreed to lowercase all HEX, and to leave Ethernet tags for Donald's
> rfc7042bis.  (despite that being informational and a possible downref issue)
> 
> We agreed that Invalid CBOR is... invalid CBOR, and that the CDDL gives the
> details for the limits.
> 
> I have posted a revision -10, which I hope satisfies all of the DISCUSS and
> comments:
> 
>  https://www.ietf.org/rfcdiff?url1=draft-ietf-cbor-network-addresses-09&url2=draft-ietf-cbor-network-addresses-10
> 
> 
> 
> --
> Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
>           Sandelman Software Works Inc, Ottawa and Worldwide
> 
> 
> 
> 
> _______________________________________________
> CBOR mailing list
> CBOR@ietf.org
> https://www.ietf.org/mailman/listinfo/cbor