.
DCE-RPC Interoperability (XDSA-DCE) - Introduction
Previous section.
Distributed Software Administration - DCE Interoperability (XDSA-DCE)
Distributed Software Administration - DCE Interoperability (XDSA-DCE)
Copyright © 1997 The Open Group
Introduction
Scope and Purpose of XDSA-DCE
This document is the X/Open Distributed Software Administration
(XDSA-DCE) specification. XDSA-DCE provides a mechanism for addressing
the interoperability needs of the POSIX 1387.2 standard for
Software Administration.
The scope of the POSIX 1387.2 standard
does not include interoperability.
The XDSA-DCE specification defines a way in which the
various distributed roles communicate and transfer
data.
This interface is one
means to achieve interoperability between different
implementations of the POSIX 1387.2 standard.
XDSA-DCE is implemented using the X/Open Distributed
Computing Environment (DCE) remote procedure calls (RPC).
The interface has no DCE run-time requirements,
although it supports the use of DCE naming and
security services when operating in a DCE cell.
XDSA-DCE is designed with the intention that it will support the
current and future versions of the POSIX 1387.2 standard
by only adding additional legal values and associated
semantics to the current RPC parameters, but not modifying the
protocol.
Scope of the POSIX 1387.2 Standard
The scope of the POSIX 1387.2 standard for software administration
includes the following:
-
A standard layout for software.
This is a common exported structure for software distributions that
contain the software organized into manageable objects.
-
A definition for information about installed software.
These are the definitions of the software objects, and the attributes
they support.
-
A standard set of commands for manipulating software.
This is the set of command definitions needed to manage the software,
as well as the behaviors associated with the software attributes.
The POSIX 1387.2 Standard
The referenced document
POSIX 1387.2
is the
IEEE POSIX Standard 1387.2-1995: Information Technology - Portable
Operating System Interface (POSIX) System Administration -
Part 2: Software Administration.
Throughout this XDSA-DCE specification, in any description of POSIX
1387.2 where a variance with this standard arises, the referenced
POSIX 1387.2
standard is the definitive specification.
POSIX 1387.2 Distributed Roles
While not defining protocols for interoperability, the
POSIX 1387.2 standard has defined the distributed model by defining
the distributed roles.
The three key roles related to interoperability are the
manager,
source
and
target
roles shown in
POSIX 1387.2 Distributed Roles
.
Figure: POSIX 1387.2 Distributed Roles
The manager role is the process that interacts with the
administrator.
It sends requests and receives results from the target role, and
sends requests and receives data from the source role.
The target role operates on software collections (performing
the administrative task). It requests and receives the actual software
files from the source role.
The source role receives requests for data or actual software files
and returns the data and software files in the software collection.
Examining the syntax of the POSIX 1387.2 standard
commands, there are four main components:
-
Target Selections
This is a list of target objects that the software specifications
will be applied to.
The target objects are manageable software collections, identified
by a host and a path.
-
Software Selections
This is a list of software specifications that identify particular
software objects to be applied to the targets.
-
Command
This is the operation to apply to the software in each target.
Most operations define an analysis phase to determine if the
operation will like succeed, and an execution phase that
actually perform the operation.
-
Options
These are used to additionally define the previous operation.
Thus, distributed operation involves sending the software
selections, command and options from the manager to each target.
Some software commands also involve
taking software from a source and transferring it (applying
it) to the target.
Therefore, distributed operation also involves the target
requesting software files for the software selections it is processing
from the source.
Terminology
This specification assumes some familiarity with the terminology
used in the POSIX 1387.2 standard.
It also uses some terms which have specific meaning for XDSA-DCE.
In particular, XDSA-DCE uses some different terms for the same concepts
described in the POSIX 1387.2 standard.
The key POSIX 1387.2 standard
and XDSA-DCE terms are defined in the Glossary at the end
of this specification.
Conformance
Mandatory
An implementation is conformant to this
specification if it implements at least the
required portions of this specification as defined in
Chapters 1 through 6.
Options
The following aspects of XDSA-DCE are optional:
- XDSA-DCE Daemon
The XDSA-DCE Daemon option is defined by
XDSA-DCE Daemon
of this specification.
- XDSA-DCE Security
The XDSA-DCE Security option is defined by
XDSA-DCE Security
of this specification.
In order for an implementation to conform to any of
these options, it must conform to all of the
specification defined for that option.
Why not acquire a nicely bound hard copy?
Click here to return to the publication details or order a copy
of this publication.