Lucent 5ESS

The Alcatel‑Lucent 5ESS Switching System is a Class‑5 digital telephone switch introduced in 1982 by Western Electric/AT&T and later maintained under Lucent and Alcatel‑Lucent. As one of the most widely deployed Class‑5 telephone exchanges, it has supported well over 100 million subscriber lines globally and has formed a core component of public telephone networks for decades.

Engineered for service provider and carrier environments, the 5ESS delivers robust, multiservice switching for voice, data, and signaling traffic. Built on a fully distributed architecture comprising Administrative, Communication, and Switching Modules, it offers reliability, scalability, and high availability across diverse operating conditions.

Carritech offers support for the full ecosystem of 5ESS hardware, line cards, and spare modules—fully tested and ready to extend the service life of legacy switching infrastructure. Whether maintaining active deployments or provisioning spares, our offerings provide continuity and peace of mind.

• Carrier-Grade Reliability
  Designed for 99.999% uptime, with fault-tolerant architecture and extensive redundancy across system components.

• Modular, Distributed Architecture
  Composed of Administrative Modules (AM), Communications Modules (CM), and Switching Modules (SM), allowing for scalable and flexible deployment.

• Multiservice Switching
  Supports voice, data, ISDN, Centrex, operator services, and intelligent network (IN) applications within a single platform.

• High Capacity
  Supports hundreds of thousands of subscriber lines and trunks, making it ideal for large-scale central office and international deployments.

• Integrated Signaling Support
  Full support for SS7 (Signaling System No. 7) and legacy signaling protocols like MF and R2, enabling global interoperability.

• Centralized Management
  Comprehensive control and monitoring via the Administrative Module, with options for remote management and diagnostics.

• Flexible Interface Options
  Supports analog, digital, and IP-based interfaces including T1/E1, DS3, and optical connections through integrated interface cards.

• Service Customization
  Offers advanced routing, call processing, and service logic control capabilities for tailored voice and data service offerings.

• Long-Term Deployment Stability
  Field-proven platform still in use worldwide, offering a reliable solution for legacy network continuity.

• Field-Replaceable Components
  Designed for easy maintenance and support, with modular cards and shelves for efficient sparing and upgrades.

System Architecture

The 5ESS Switching System uses a modular, distributed architecture made up of three main components:

• Administrative Module (AM)

  • Central processor for call processing, operations, maintenance, and control functions

  • Runs UNIX-based software for service logic and system configuration

  • Supports remote access, alarms, diagnostics, and billing interfaces

• Communications Module (CM)

  • Handles time-slot interchanges and manages signaling and message transport

  • Acts as the switch’s internal messaging and synchronization hub

  • Provides interfaces between AM and all Switching Modules (SMs)

• Switching Module (SM)

  • Local processor for handling line and trunk interfaces

  • Performs call setup, digit analysis, and voice switching

  • Can operate autonomously even if the AM or CM is unavailable

  • Each SM can serve thousands of lines or trunks

Capacity

• Line Capacity: Up to 100,000+ subscriber lines per system

• Trunk Capacity: Scales to thousands of T1/E1/DS3 trunks

• Port Density: High-density shelves and line cards for efficient rack space usage

• Call Processing Rate: Thousands of calls per second under full load

Interfaces & Protocols

• Telephony Interfaces:

  • Analog POTS

  • ISDN BRI/PRI

  • T1/E1, DS0, DS1, DS3

  • SONET/SDH via add-on transport modules

• Signaling Support:

  • SS7 (ISUP, SCCP, MTP)

  • MF, R1, R2

  • GR-303, V5.2 for remote access nodes

  • SIP (via interworking units in modern deployments)

Services Supported

• Basic and enhanced voice services

• ISDN and Centrex

• Operator services

• Emergency call routing

• Intelligent Network (IN) services

• Voice and data integration with legacy and modern networks

Reliability & Maintenance

• Redundant Processors: Dual processors for AM and SMs with automatic failover

• Power: Dual power inputs; supports DC and AC configurations

• Diagnostics: Built-in test access, error logs, and status indicators

• Hot-Swappable Modules: Most components are field-replaceable without service interruption

Management & Control

• Local or remote management via the AM

• UNIX-based software environment for administration and provisioning

• Alarm systems with thresholds and triggers

• Compatibility with external operations support systems (OSS)

Physical & Environmental

• Mounting: Floor-standing cabinet systems; some configurations allow for rackmount

• Cooling: Forced air with redundant fans

• Operating Temperature: Typically 0°C to 40°C (indoor environments)

• Power: -48V DC typical; battery backup systems optional