Alcatel‑Lucent 107486490 DDM‑2000 SONET DS3 Circuit Pack – BBG4B S1:1
The Alcatel‑Lucent 107486490 is a DS3 circuit pack specifically designed for the DDM‑2000 SONET multiplexer platform. Designated as BBG4B S1:1, this line card provides high‑density DS3 (44.736 Mbps) interface connectivity, aggregating up to 28 DS1 (T1) signals into a single DS3 stream, and subsequently mapping this into a SONET STS‑1 payload for optical transmission over standard OC‑3, OC‑12, or OC‑48 rings.
Product Description
The DDM‑2000 (Digital Data Multiplexer) is a legacy but still widely deployed SONET add‑drop multiplexer in many regional carrier networks. The 107486490 circuit pack serves as the primary interface for legacy digital cross‑connect systems and PBX trunks. It supports both M13 multiplexing (mapping 28 DS1s to DS3) and direct DS3 termination, offering flexible grooming options for service providers transitioning from TDM to packet‑based infrastructures.
The BBG4B variant features enhanced clock recovery and jitter attenuation, ensuring compliance with both Bellcore and ITU‑T performance standards. The S1:1 suffix indicates a specific hardware revision with improved surge protection and extended temperature tolerance for outdoor or lightly conditioned shelters.
Technical Specifications
Product Type: SONET DS3 Circuit Pack
Part Number: 107486490
Platform: Alcatel‑Lucent DDM‑2000
Designation: BBG4B S1:1
Ports: 4 x DS3 (coax, BNC connectors)
Data Rate: 44.736 Mbps per port (DS3)
Line Coding: B3ZS
Multiplexing: M13 (DS1 to DS3) and C‑bit parity
SONET Mapping: STS‑1 (51.84 Mbps) with VT mapping
Performance Monitoring: DS3 far‑end block errors (FEBE), line code violations
Power Consumption: 35 W typical
Operating Temperature: 0°C to 50°C
Dimensions: Standard DDM‑2000 single‑slot module
Key Features and Functions
High‑density DS3 termination for efficient cable utilization.
Integrated M13 multiplexer to aggregate T1 traffic directly.
Hitless protection switching when used in 1:1 or 1:N configurations.
Comprehensive diagnostics including loopback (line, payload, and system).
Real‑time performance monitoring against GR‑499 and GR‑253 standards.
Automatic protection switching (APS) coordination via SONET K1/K2 bytes.
Deployment Scenarios
This circuit pack is typically installed in central office DDM‑2000 shelves to interconnect with legacy tandem switches and digital cross‑connects (DCS). It also connects to microwave backhaul radios that transport DS3 signals as an intermediate step before being handed off to IP routers. In enterprise campus networks, it can aggregate DS3 feeds from multiple buildings onto a resilient SONET ring.
The S1:1 revision supports both dual‑feed and single‑feed operation, making it versatile for applications with redundant power sources.
Integration and Maintenance
The circuit pack is managed through the DDM‑2000’s local craft interface or via the network management system using TL1 commands. It reports detailed statistics such as errored seconds, severely errored seconds, and unavailable seconds. Replacing the card is a hot‑swappable operation, and the system automatically restores active alarms upon insertion.
Compliance
Complies with ANSI T1.107, Bellcore GR‑499, and ITU‑T G.703 for DS3 interfaces. It also meets NEBS Level 2 requirements for electromagnetic compatibility.
Conclusion
The Alcatel‑Lucent 107486490 DDM‑2000 DS3 Circuit Pack remains a reliable, high‑performance solution for TDM aggregation and SONET transport. Its robust feature set, proven reliability, and seamless integration with legacy infrastructures make it a valuable asset for maintaining existing service commitments.




