An Introduction to the Ericsson Transport Network Architecture ...

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BOX 3
The SDH NE MANAGEMENT ORGANISATION­
AL MODEL
Management of SDH NEs is based on the management
organisational model as outlined in Ret
5. The model consists of the following TMN function
blocks and components, Fig. A: The Network
Element Function (NEF) including the Management
Information Base (MIB), the Message Communication
Function (MCF), and the Management
Application Function (MAF) including the agent.
In addition, an MAF functional component containing
a manager for local control of the NE has
been defined. The local manager is housed in the
local operator's terminal.
Agent
Part of the MAF which is capable of responding
to network management operations issued by
a manager, and of issuing notifications, e.g.
event reports, on behalf of the managed objects
Manager
Part of the MAF which is capable of issuing requests
for network management operations,
e.g. request performance data, set thresholds,
receive event reports, etc.
Local Manager
A managerwhich is housed in a local operator's
terminal and is capable of managing a single
network element
Management Application Function (MAF)
An application process providing TMN services.
The MAF includes an agent, or a manager, or
both. The MAF is the origin and termination of
all TMN messages
Managed Object (MO)
The manager's view of a resource within the
telecommunications environment that may be
managed via the agent. Examples of MOs residing
in an SDH NE are equipment, software,
trail termination point, SDH switch fabric, alarm
log, etc.
Message Communication Function (MCF)
Provides facilities for the transport of TMN messages
to and from the MAF, as well as network
layer routing functions
Network Element Function (NEF)
The entity within an NE that supports transport
network based services, e.g. multiplexing,
cross-connection, regeneration, etc. The NEF
is represented to the manager as a set of managed
objects.
ECC subnetwork, or between any of the
ECC subnetworks, Boxes 2 and 3.
Graphical User Interface
General
One of the most important aspects of
SDH NE management is the ease with
which it can be operated.
It is true that a prime driving force behind
the deployment of the Transport Network
is to facilitate the management of network
resources by way of centralised management
- that is, with Q-interfaces and FMAS
- but NEs will nevertheless be operated
and maintained from the local site. Some
of the reasons for local operation are:
- Backup when the OS, or the communication
link to OS, is down
- The network operator may wish to adopt
a more decentralised management philosophy
- Certain management functions are more
easily performed on site because they
require physical manipulation of the
equipment.
For this purpose a local operator's terminal
with a Graphical User Interface (GUI)
can be connected to the NE. The GUI is a
window-based and mouse-operated interface
through which the operator has access
to all the management functions.
In order for an operator to gain access to
the functionality, he has to prove his legitimacy
by supplying an identification code
and a password. This falls under Security
Management, which also includes the possibility
of a Super-user assigning operators
to particular user categories with extensive
or more limited privileges.
Configuration Management covers both
physical configuration in an SDH NE-typically
Printed Board Assemblies such as
Fig. A
SDH NE Management Organisational Model
ERICSSON REVIEW No. 3, 1992