Subject: service URLs and naming authorities

From: David Arnold <[email-masked]>
Date: Wed, 17 Feb 1999 16:03:17 +1000

in implementing the SrvTypeRqst operation, i have come across some
apparent ambiguity wrt naming authorities in service: URLs.

in short, is it possible for both the abstract and concrete components
of a service type name to have naming authorities?  if so, can they be
different?

looking at the examples in protocol-v2-12 section 4.1, it would seem
that when both abstract and concrete components are present, only the
abstract component can have a naming authority?

the Java API also has a single getNamingAuthority() method for the
ServiceType class, hinting that either both NAs must be the same, or
that a service type can have only one.

a second problem: the service: URL ABNF grammar in service-scheme-14
section 2.1 also seems to indicate that a service-type cannot consist
solely of an abstract-type.

the relevant portion of the grammar is

  service-type    =   abstract-type ":" url-scheme / concrete-type
  abstract-type   =   type-name [ "." naming-auth ]
  concrete-type   =   protocol [ "." naming-auth ]

can anyone clarify the intent here?

thanks,

-- David Arnold   ,=================================================
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CRC for Distributed Systems Technology         +617 33654311   (fax)
University of Queensland                    [email-masked] (email)
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---

From: James Kempf <[email-masked]>
Date: Wed, 17 Feb 1999 15:05:35 -0800 (PST)

>
>just as a note, the grammar does not appear to define "protocol" (as
>used in concrete-type).  i'm assuming it's a resname with some
>usage restrictions?
>

Yes, protocol is a resname. The idea is that it could be an application
protocol, but it could also be something else. An example of such
a service type name might be "service:airline-tickets" for a service
that does airline ticketing.

		jak