Filter
Top Products
2. CPX-1000 Voice Services Platform Description 1000-A2-GN22-00
2-32 February 2003
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:
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.
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.
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.
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.