Automatic switchover—the system detects a problem such as loss of signal and performs a forced switchover to the standby ATM module in the protection group.

2. CPX-1000 Voice Services Platform Description

1000-A2-GN22-00

 

 

ATM OC-3 Module

The ATM OC-3 module (coming in through the transition card) is the WAN interface that connects a CPX shelf to an ATM access network using an OC-3 optical interface. The ATM module performs real time circuit-to-packet conversion that allows an ATM-based access network to deliver local telephone service.

The CPX protects the ATM connection to the packet network against physical facility failure and far end equipment failure. In a switchover scenario, the CPX executes the transition from the working to the protection port to ensure no services are disrupted.

On power up, the presence of the ATM modules in the shelf is detected. Before ATM switchovers can occur, however, use JetCraft or JetVision to assign them to a protection group so that the primary and secondary modules can be designated. When the ATM modules are unlocked, the primary ATM module becomes active and the secondary ATM module becomes standby.

This architecture enables two types of ATM module switchovers:

￿Administrative switchover—the network administrator ￿initiates a CP switchover using JetCraft or JetVision. A

forced switchover always goes through regardless of voice traffic and active cells remain up.

Voice/Data Interruption

Calls that are in the process of being set up are lost during a forced switchover. Calls that are established and carrying voice traffic, however, survive a switchover.

The active and standby states for each ATM module is persistent. The CPX continuously monitors the health of redundant ATM modules and switches to standby ATM module if instructed to do so by software or user intervention. The CPX issues appropriate alarms and events to notify users that the switchover has been initiated and indicates the success or failure of a switchover.

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February 2003

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Paradyne CPX-1000 manual ATM OC-3 Module