Alcatel-Lucent IMM48-1GB-TX (3HE03625AAA001) 48-Port Gigabit Ethernet Line Card – Complete Overview

The Alcatel-Lucent IMM48-1GB-TX, identified by the product code 3HE03625AAA001, is a high-density 48-port Gigabit Ethernet line card designed for the 7750 SR-12 service router chassis. This module provides 48 independent 10/100/1000BASE-T copper ports, offering a cost-effective and space-efficient solution for aggregating large numbers of subscriber connections in metro Ethernet, enterprise, and mobile backhaul networks. Its advanced feature set and wire-speed performance make it a cornerstone of modern IP/MPLS infrastructures.

Each of the 48 ports supports auto-negotiation for speed and duplex, as well as auto-MDI/MDIX crossover detection, simplifying cabling and installation. The ports are arranged in four groups of twelve, with LEDs on the front panel indicating link status, activity, speed, and duplex mode. The card includes integrated cable diagnostics that can detect opens, shorts, and cable length, aiding in field troubleshooting.

At the core of the IMM48-1GB-TX is a powerful network processor that handles all packet forwarding, classification, and queuing operations in hardware. The card delivers line-rate forwarding of up to 96 Gbps (full duplex) across all ports, with a packet forwarding rate exceeding 35 million packets per second (Mpps) for 64-byte frames. This performance is sustained even with complex service operations such as VLAN translation, MPLS label processing, and access control list (ACL) filtering.

Quality of Service (QoS) is a primary strength. The card supports hierarchical QoS (HQoS) with eight hardware queues per port, configurable for strict priority, weighted round-robin (WRR), or deficit WRR scheduling. Policing and shaping are available at both port and queue levels, with dual-rate three-color marking (CIR/PIR) for granular bandwidth control. Congestion management includes Weighted Random Early Detection (WRED) to optimize throughput during transient overloads.

Service awareness is comprehensive. The card supports IEEE 802.1Q VLAN tagging, QinQ stacking, VLAN translation, and IEEE 802.1ad Provider Bridging. In the MPLS domain, it handles MPLS-TP, LDP, and RSVP-TE, enabling traffic engineering, fast reroute (FRR), and Virtual Private LAN Service (VPLS). The card also supports IPv4 and IPv6 routing with OSPF, IS-IS, and BGP protocols, making it suitable for both Layer 2 and Layer 3 service delivery.

Security features include port-based authentication via IEEE 802.1X, MAC address lockdown, DHCP snooping, and Dynamic ARP Inspection (DAI). Access Control Lists (ACLs) can be defined on Layer 2, Layer 3, and Layer 4 fields, with hardware-based filtering at wire speed. The card also supports sFlow and NetFlow-like sampling for traffic visibility and anomaly detection.

Synchronization is supported through Synchronous Ethernet (Sync-E) and IEEE 1588v2 Precision Time Protocol (PTP) with hardware timestamping, essential for mobile backhaul and TDM emulation applications. The card can derive timing from the chassis backplane or external BITS sources.

Management and diagnostics are integrated with the 7750 SR's TiMOS operating system. The card provides extensive performance monitoring per port, including RMON statistics, error counters, and historical utilization data. It supports remote loopback tests, RFC 2544 and Y.1564 service activation tests, and packet capture for deep inspection. Alarms are forwarded via SNMP and syslog to the network management system.

Physical design emphasizes reliability. The card is a full-height module that fits into any slot of the 7750 SR-12 chassis. It is hot-swappable, allowing insertion or removal without system power-down. The operating temperature range is 0°C to 50°C, with forced-air cooling from the chassis fan trays. The card includes redundant power feeds from the backplane and ECC protection for all memory.

Compliance includes NEBS Level 3 (GR-63-CORE, GR-1089-CORE), ETSI EN 300 386, and FCC Part 15. The card meets RoHS and REACH directives, and carries CE and UL certifications. Its MTBF is rated at over 300,000 hours.

Typical applications include subscriber aggregation in broadband access networks, enterprise LAN switching, and mobile backhaul transport. The IMM48-1GB-TX provides the density and performance required for network consolidation and service expansion, making it a valuable investment for operators planning for future growth.

In summary, the Alcatel-Lucent IMM48-1GB-TX is a versatile, high-performance line card that combines density, feature richness, and reliability. Its advanced QoS, security, and synchronization capabilities make it an ideal choice for delivering converged services over IP/MPLS networks.