Specifications

DXC-100PSX Overview 1-1
Chapter 1
Overview
1.1 Overview
Purpose and Use
The DXC-100PSX N+1 Protection Switch provides automatic backup for failed
narrowband (D8E1T1) and/or broadband (DT3 or DE3) module sets in a DXC-100
Multiservice Access Node, whether used as a standalone or as part of a stack.
The backup is accomplished by providing a redundant (spare) module set within
the DXC-100 of identical type as the primary module(s) being protected. Both the
spare and primary modules are configured into protection groups, which are
monitored by the System Manager module (DSMC.2 or DXNM). When the DSMC.2
determines that there is a problem with one of the primary modules and a
switchover is required, it will configure the spare to match the defective primary
module and will then command the DXIP to transfer the network traffic to the
redundant module set, via interface relays. This design allows the link to resume
operation without user intervention, and with only a minimal amount of
downtime.
The generic term SMC is used to refer to either type of System Manager module,
DSMC.2 or DXNM. The full designation is used when the information is applicable
only to a specific module type.
Main Features
The primary function of the DXC-100PSX N+1 Protection Switch is to allow a
DXC-100 operated in a stack or as standalone to carry redundant Narrowband
(D8E1T1) or Broadband (DT3 or DE3) module sets, which provides the user a
backup capability in the event that a Broadband or Narrowband module becomes
non-operational. With the DXC-100PSX in place, the non-operational module
should be switched to a backup module. This allows the system to reconfigure
links and continue operating with minimum down time and without any user
intervention.
The following conditions will cause a switchover from the primary to the standby
module:
• Front or rear card is not present
• Channel card encounters system fatal errors
• Channel card not receiving message from the SMC
Note