Nortel AL2033008 (telecommunications transmission and networking portfolio) Telecom System Card / Module

The Nortel AL2033008 is a BayStack 450-1LR Media Dependent Adapter (MDA), a single-port 1000Base-LX gigabit fibre module with redundant PHY (physical-layer) circuitry built in for the BayStack 350 and 450 switch families and the compatible Passport 8000 series Edge Switch. It plugs into the MDA slot on a BayStack 450 chassis to add a long-reach single-mode fibre uplink, and the redundant-PHY design pairs with Nortel’s LinkSafe technology to automatically fail over to a backup physical link if the primary fibre path is lost, without needing the switch to be reconfigured or reset. This is a step up from the simpler single-PHY 450-1SX module used for shorter multimode runs, aimed at sites where the fibre uplink itself is the single point of failure worth protecting. BayStack 450 switches were a common stackable-switch choice for wiring-closet and small-core deployments through the 2000s, and many remain in service where the MDA slot format lets a site add gigabit fibre uplinks without a full switch replacement. Tech-Star (UK-based, shipped worldwide) carries BayStack MDAs for network maintenance and upgrade work.