Re: Z39.50 diagnostics in Init response

Mike Taylor wrote:

> What's the problem here?  We agreed to deprecate it because we
> couldn't think of a way it was being used.  Now we've thought of a
> way, so let's not deprecate it.

The Diag-1 definition has two parts:

     (1)  "defaultDiagRec"
     (2) "explicitDiagnostic"

While the defaultDiagnostic part is useful, the explicit diagnostic part,  a
long and elaborate ASN.1 representation of diagnostics, most everyone agrees, is
useless baggage. (And it's about 90% of the definition; the default part was
thrown in, literally, as an afterthought.)

Please correct me if I'm wrong on that latter point. It's been my perception
that it's not useful to anyone, and when I proposed (last summer) to depricate
it, nobody objected. We did expect it would be useful when we defined it in
1994, but  I have never heard anyone say they've implemented it.

So it seems unfortunate to have to carry along the baggage to retain the useful
part.  My point is, we don't have to.  Even though the "default" part is useful,
and its functionality is necessary, we have the "General-diagnostic container"
that also provides this functionality (and more),  more directly and more
elegantly.

We could keep both, but consider the drawbacks: (1) there would be two different
ways to provide a diagnostic container --  Diag-1 on an Init response and
General Container for encapsulation and (2) if we retain  Diag-1, we retain its
elaborate ASN.1 definition of diagnostics that will never be implemented, and
that just adds to the perception of Z39.50 as a bloated standard.

So what do people suggest we do?

If anyone has implemented the "explicit" part, then we'll re-instate the full
Diag-1 (that is, not depricate it).

Assuming not, if anyone has implemented the default part, then we could
re-define Diag-1, for the purpose of retaining the OID, removing the explicit
part.  If we do that, then we need to know: has anyone implemented the
Diagnostic Container? If not we could make Diag-1 a well-known object and use it
instead, where the Container is currently prescibed.

But if nobody has implemented any of Diag-1, please, let's just depricate it.

--Ray

--
Ray Denenberg
Library of Congress
rden@loc.gov
202-707-5795