Nortel NTFN48DD (telecommunications transmission and networking portfolio) Telecom System Card / Module

The Nortel NTFN48DD is a four-port DS1 Next Generation function processor, standard variant, for the Passport 6400/7400 wide-area switching platform. DS1 is the North American equivalent of the E1 trunk standard (1.544Mbit/s over 24 channels), and this card terminates four DS1 circuits into the Passport shelf’s switching fabric, giving carriers and enterprises running Passport nodes in DS1-standard territories the same tributary density that the E1-based NTFN cards provide elsewhere. The ‘Next Generation, Standard’ designation places it in the same function-processor generation as the E1 NTFN48 variants, differing in the trunk standard it terminates and stopping short of the higher-specification ‘Premium’ NTFN cards built for additional protocol features. Passport 6400/7400 nodes deployed on DS1-standard networks remain in service handling legacy TDM, Frame Relay and ATM tributaries that have not yet been migrated to Ethernet aggregation. Tech-Star (UK-based, shipped worldwide) supplies Passport DS1 function processors for ongoing node maintenance.