[Cbor] CBOR tags for IPv4 and IPv6 addresses and prefixes

[Michael Richardson <[e-mail]>]

I was not satisfied with the semantics of tag 260 and 261.

The IP address type is determined by the length of the item.
Aside from lacking semantic meaning, it forces me to put all the trailing zeros in.
(Also IEEE now has 8-byte MAC addresses)

I'm happy to leave 260 for mac addresses though.
Should the prefix length go first perhaps?

I prefer the encoding given below (oops got my Doc prefix for IPv4 wrong in
document, fixed below):


## IPv6

IANA has allocated tag TBD1 for IPv6 uses.

An IPv6 address is to be encoded as up to sixteen-byte bytestring ({{RFC8949}} section, 3.1, major type 2), prefixed with tag TBD1.  Trailing zero octets may be omitted.

An IPv6 prefix, such as 2001:db8:1234::/48 is to be encoded as a two element array:

~~~~
    TBD1([ h'20010db81234', 24])
~~~~

## IPv4

IANA has allocated tag TBD2 for IPv4 uses.

An IPv4 address is to be encoded as a four-byte bytestring ({{RFC8949}} section, 3.1, major type 2), prefixed with tag TBD2. Trailing zero octets may be omitted.

An IPv4 prefix, such as 192.0.2.1/24 is to be encoded as a two element array:

~~~~
    TBD2([ h'C0000201', 24])
~~~~





[e-mail] wrote:
    > A new version of I-D, draft-richardson-cbor-network-addresses-00.txt
    > has been successfully submitted by Michael Richardson and posted to the
    > IETF repository.

    > Name: draft-richardson-cbor-network-addresses Revision: 00 Title: CBOR
    > tags for IPv4 and IPv6 addresses and prefixes Document date: 2021-01-25
    > Group: Individual Submission Pages: 4 URL:
    > https://www.ietf.org/archive/id/draft-richardson-cbor-network-addresses-00.txt
    > Status:
    > https://datatracker.ietf.org/doc/draft-richardson-cbor-network-addresses/
    > Html:
    > https://www.ietf.org/archive/id/draft-richardson-cbor-network-addresses-00.html
    > Htmlized:
    > https://tools.ietf.org/html/draft-richardson-cbor-network-addresses-00


    > Abstract: This document describes two CBOR Tags to be used with IPv4
    > and IPv6 addresses and prefixes.

    >    RFC-EDITOR-please remove: This work is tracked at
    > https://github.com/mcr/cbor-network-address.git




    > Please note that it may take a couple of minutes from the time of
    > submission until the htmlized version and diff are available at
    > tools.ietf.org.

    > The IETF Secretariat



--
Michael Richardson <[e-mail]>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide