Nortel NTEU20AA STM-4 Optical Aggregate Card 1310nm SH FC/PC

The Nortel Networks NTEU20AA is a dual-port STM-4 optical aggregate card designed for the OPTera Metro 3500, TN-4XE, and other Nortel multiservice SDH/SONET platforms. It provides two independent bidirectional STM-4 optical aggregate interfaces operating at the nominal line rate of 622.08 Mbit/s.Each port uses a 1310 nm Fabry-Perot (FP) laser transmitter and a PIN photodiode receiver, classified as Short Haul (SH) / S-4.1 according to ITU-T G.957 and Telcordia GR-253 standards. The module is optimized for single-mode fiber (SMF 9/125 µm) with a typical transmission distance of up to 2 km. Optical connectors are FC/PC type. Transmitter output power and receiver sensitivity ensure reliable performance with low bit error rates (better than 10⁻¹²) over short-haul distances.
The NTEU20AA functions as an aggregate card, supporting the termination of STM-4 optical signals for the platform’s main traffic paths. It handles full section, line, and path overhead processing for STM-4 signals and enables multiplexing/demultiplexing of lower-order tributaries (VC-12, VC-3, VC-4) when combined with tributary and cross-connect cards in the shelf. The card occupies a dedicated aggregate slot in the OPTera Metro shelf and interfaces electrically with the backplane for high-speed data transport, synchronization, and management communication.
Key features include Loss of Signal (LOS) detection on each port, automatic laser shutdown (ALS) for eye safety (Class 1 laser product), and comprehensive performance monitoring including BIP-24 error checking, signal degrade, and signal fail thresholds. Alarms and status information are reported in real time to the shelf controller and forwarded to the network element management system for centralized fault isolation and performance management.
The module derives power from the shelf backplane at nominal -48 V DC with optimized consumption for aggregate traffic handling. It supports hot-swappable replacement in systems with redundant configurations where applicable. Environmental specifications follow standard telecom requirements: operating temperature range typically 0°C to +55°C, with humidity tolerance up to 95% non-condensing. Built-in surge and ESD protection ensure stable operation in central office environments.
This aggregate card is primarily used for STM-4 optical backbone connections in metro and regional SDH networks, serving as the main traffic entry/exit point for the OPTera Metro node. It enables efficient aggregation of multiple lower-rate tributaries into higher-capacity STM-4 links and supports ring, linear, and mesh topologies when combined with other aggregate and tributary cards. The NTEU20AA is fully compatible with Nortel’s OPTera Metro platform and integrates with the element management system for remote provisioning, software upgrades, and detailed performance data collection.
Installation requires proper fiber cleaning, correct Tx/Rx polarity on the FC/PC connectors, and adherence to minimum bend radius guidelines. The NTEU20AA provides a reliable and high-performance solution for dual STM-4 short-haul optical aggregation in legacy Nortel (now Ciena-supported) multiservice transport systems