ATL Telecom OM100 User Manual

Page 14

Operating The OM100 in an SDH Environment

Note: This section describes a feature of the OM100 for advanced users only. The default
mode of operation will suit most applications.

In its default mode, the OM100 is purely plesiochronious. The four E1 user ports can transmit
and receive data at (slightly) differing rates. Each, and every clock is truly independent of the
others. E1 links can be sourced from the same timing source, up to eight independent timing
sources, or a mixture of both.

Network operation for clock synchronisation at the PDH end nodes requires selection of the
"lock clock" option from the user port configuration screen. External reference timing is
derived from user port one. Transmit clocks are re-timed and synchronised to the received
clock at the master unit on user port one.

SDH Operation Timing

PORT1

PORT2

PORT3

Master unit

PORT1

PORT3

PORT4

Slave unit

PORT4

PORT2

Lock Clock

Enable to Reference

Port 1 [X]

Port 2 [X] [X]

Port 3 [X] [X]

Port 4 [X] [X]

PORT1

PORT2

PORT3

PORT4

Master unit

PORT1

PORT2

PORT3

PORT4

Slave unit

Lock Clock

Enable to Reference

Port 1 [X]

Port 2 [X] [ ]

Port 3 [X] [ ]

Port 4 [X] [ ]

ATL USER GUIDE

OM100 Optical Multiplexer

ATL USER GUIDE
OM100 Optical Multiplexer

3.6.2

Configuring the user ports

The unit is supplied with all four user ports enabled. Disabled ports block traffic, replacing it
with an AIS pattern. To configure the ports, you must logon to the management port as
described in section 4, and follow the menus to ‘Configuration->User Port’ as shown in
section 7. Section 6 explains how to change the data on the configuration screen.

User ports can be configured by connecting a terminal to either the master, or slave unit. If the
configuration is carried out before the optical connection is made, the parameters stored in
the master unit will overwrite those stored in the slave.

Function

A disabled user port will prevent the customer from gaining useful access.
AIS is continually transmitted both towards the customer and the exchange.
The incoming traffic is blocked, no monitoring takes place, and no response
functions are active. Disabling a port disconnects it logically from the network.

An enabled (default) port will give the customer full access.

In its default mode (off), the OM100 is purely plesiochronious. The E1 user ports
can transmit and receive data at (slightly) differing rates. Each, and every clock is
truly independent of the others.

When on, transmit clocks are re-timed and synchronised to the received clock at
the master unit, on user port one.

Field

Enable

Lock Clock
to Ref.

OM100 Mon 01 Nov 2002 00:34:32

Config > User Ports

Urgent Alarm:On Non-Urgent Alarm:Off

Subsystem: LT

Lock Clock

Enable to Reference

Port 1 [X]

Port 2 [X] [ ]

Port 3 [X] [ ]

Port 4 [X] [ ]

Press Return to Accept or Escape to Cancel

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