Subject: RE: ASN.1 vs XML

From: "David P. Kemp" <[email-masked]>
Date: Fri, 9 Jul 1999 15:38:08 -0400 (EDT)

> From: Paul Koning <[email-masked]>
> 
> >>>>> "BalluffiF" == BalluffiF  <[email-masked]> writes:
> 
>  BalluffiF> ASN.1 is a syntax that enables protocol engineers to
>  BalluffiF> communicate abstractly about bits that may travel down a
>  BalluffiF> wire, ...
> 
> True.
> 
> I think when people say "ASN.1" they really mean "ASN.1 and BER and
> DER" -- and in fact most of the objections are to the latter two, not
> to ASN.1 as an abstract notation.
> 
> 	paul

Yes and no.

I think most people do mean ASN.1 and BER, but I'm not sure that the
objections are mainly to BER or DER.  I believe the objections are to
the use of any formal syntax, because such systems (may)
have a separate compilation step to produce encoders and decoders.

As Paul Hoffman says, it's easier for Perl to parse/emit XML than BER
(although a Perl BER module, which I haven't used, does exist).  But
Perl does not support going directly from *any* formal syntax to
*any* encoding - the encoding and parsing modules must be handcrafted by
someone from some other type of syntax specification.

Anyone who says "Anything but ASN.1/BER" should specify which syntax
language (prose, bits-n'-boxes, ABNF, yacc grammar, ASN.1, ...) and which
encoding/marshalling mechanism (bits-in-a-packet, XML, XDR (RFC 1832),
BER/DER, S-expressions, ...) they are advocating as an alternative, and
provide a full translation of X.509 certs and standard extensions into the
proposed syntax language.  The results of that exercise might be an
eye-opener, and afterwards ASN.1 might not look so ugly after all.