Alcatel-Lucent 3AL34291AA legacy SDH/PDH transmission Optical Transmission Module

The Alcatel-Lucent 3AL34291AA is an L-4.1 STM-4 long-haul optical aggregate interface card, designed for Alcatel-Lucent’s legacy SDH transmission shelves. The L-4.1 designation marks this as a long-haul optical variant operating at the STM-4 rate (622 Mbit/s), built to support aggregate links that need to reach further than a standard short-haul optical budget would allow, typically used to connect network sites across metro or regional distances. It fits into the aggregate slot of a compatible Alcatel-Lucent SDH shelf, carrying the multiplexed tributary traffic between sites as the shelf’s optical line-side interface. As a field-replaceable plug-in module, it allows maintenance engineers to restore or extend long-haul aggregate capacity on an in-service ring without disrupting the rest of the shelf. Operators maintaining legacy SDH backbone links continue to source tested spares of this kind rather than commit to a full platform upgrade. Tech-Star (UK-based, shipped worldwide) supplies tested Alcatel-Lucent legacy SDH optical spares including this aggregate card. Get in touch to confirm optical budget and shelf compatibility before ordering.