Re: [Cbor] I-D Action: draft-ietf-cbor-network-addresses-02.txt

Carsten Bormann <cabo@tzi.org> Wed, 09 June 2021 09:30 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Subject: Re: [Cbor] I-D Action: draft-ietf-cbor-network-addresses-02.txt
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I just had occasion to check RFC 8992 (should have done that earlier, ouch).

Apart from this nice piece of CDDL, repeated all over the place (yes, the rest is missing each time):

     objective-flags /=          ; as in the GRASP specification

… I find:

     prefval /= pref6val
     pref6val = [version6, length, ?prefix]
     version6 = 6
     length = 0..128             ; requested or offered prefix length
     prefix = bytes .size 16     ; offered prefix in binary format

     prefval /= pref4val
     pref4val = [version4, length4, ?prefix4]
     version4 = 4
     length4 = 0..32             ; requested or offered prefix length
     prefix4 = bytes .size 4     ; offered prefix in binary format

Maybe we should supply some CDDL in draft-ietf-cbor-network-addresses so people don’t start to copy the above whenever they need a prefix.

Grüße, Carsten