Re: I-D ACTION:draft-ietf-smime-escertid-00.txt

Peter,

You are perfectly right.

My mistake.

Denis

> > The current ASN.1 in RFC 2634 is:
> >
> >   ESSCertID ::=  SEQUENCE {
> >        certHash                 Hash,
> >        issuerSerial             IssuerSerial OPTIONAL
> >   }
> >
> > The proposal from draft-ietf-smime-escertid-00.txt is:
> >
> >      ESSCertIDEx ::=  SEQUENCE {
> >           certHash                 Hash,
> >           hashAlg                  AlgorithmIdentifier DEFAULT {id-sha256},
> >           issuerSerial             IssuerSerial OPTIONAL
> >      }
> >
> > The proposal made on the PKIX mailing list is:
> >
> > ESSCertIDv2 ::= SEQUENCE {
> >    certHash         OCTET STRING,
> >    issuerSerial     IssuerSerial,
> >    hashAlgorithm    AlgorithmIdentifier DEFAULT { sha-1 }
> >
> > The advantage of the last proposal is backward compatibility with the
> > existing structure. 
> No it isn't, you've lost the 'OPTIONAL' on issuerSerial, making it non-
> backwards-compatible.  If you want it to have the properties you claim it has,
> you'd need:
>
> ESSCertIDv2 ::= SEQUENCE {
>    certHash         Hash,
>    issuerSerial     IssuerSerial OPTIONAL,
>    hashAlgorithm    AlgorithmIdentifier DEFAULT { sha-1 }
>
> Peter.