Question 2/X - New Recommendations and maintenance of existing
Recommendations
to account for centralized environments

Considering

- that Recommendation Z.301 states that the Recommendations of the
Z.300-Series apply equally to centralized as well as local environments;

- that under the current Recommendations, it is not clear how some
functions (e.g. user identification) can be implemented in a centralized
environment;

- that the evolution of telecommunication networks points to an ever-
increasing role played by centralized environments,

What new Recommendations and/or changes to existing Recommendations are
needed such that both local and centralized environments are fully
supported for all man-machine interface applications?

Note - Close collaboration is required with Study Group IV, IEC and ISO.

ANNEX

(to Question 2/X)

Standardization of operation and maintenance centres (OMC)
and MML commands supplied by different manufacturers

Abstract

Experience indicates that in a country with sufficiently large demand,
there is a tendency to have more than one switching system in service,
and that, due to the advantages of centralized operation and maintenance
in a digital switching system, administrations are going to introduce
OMC in their network. The CCITT should therefore consider the matter in
order to enable telecommunication administrations to utilize a single
OMC and operators command code for different systems.

Introduction

In order to maintain competition between suppliers and to prevent a
single manufacturer from monopolizing the market, telecommunication
administrations intend to use at least two digital switching systems
manufactured by different companies.

At the moment, an OMC offered by one supplier cannot be utilized to
maintain and control a local/transit digital switching system
manufactured by another supplier. In order to have unified OMC in the
network and to facilitate maintenance outside existing interface
standards, there should be a Recommendation to unify OMC software,
especially with regard to input/output format.

Moreover, despite the availability of a command list manual according to
MML rules by different manufacturers, command codes differ from one
supplier to another.

The following is an example of creating a subscriber in two systems, A
and B:

System A --> CR SUB: DN = XXX, EQN = XXX, SCOS = XXX, ...
System B --> SOD : N = XXX, EL = XXX, LC = XXX, ...

In both systems, commands are used for the same purposes.

Proposal

It is proposed that in drawing up Recommendations the CCITT should
consider the following objectives:

1) defining a standard OMC with the required facilities and unifying the
necessary functions with a view to providing administrations with a
unique OMC for maintaining and controlling different switching systems
supplied by different manufacturers;

2) unifying all command codes which are not system-dependent.