Re: lastVerified: optional vs. extension

[Joe Abley <jabley@isc.org>]

On Friday, Dec 6, 2002, at 11:14 Canada/Eastern, Hollenbeck, Scott 
wrote:

>> Error codes are not extensible, with the
>> consequence that some existing registries put additional
>> error codes in the free
>> text elements (which are not thought to be parsed).
>
> Again, not true.  Additional errors and error codes can be defined 
> using the
> extension mechanism.  If implementers are putting additional error 
> codes in
> inappropriate free text elements they're extending the protocol 
> improperly.

Do you have any examples of how this works?

Suppose I want to add an additional server system failure result code 
(say, 2309, "openreg-specific failure of some kind"). How could I add 
that in such a way that clients connecting to me could distinguish it 
from some future revision of the spec that defines 2309 differently, or 
some other registry which makes its own use of 2309?


Joe