Table of Contents:

Definition and Overview

1. Introduction

2. Softswitch Architectural Overview

3. Network Element Failure Scenarios in the Network Office

4. High-Availability Techniques for the Network Office

5. Software Failure Analysis

6. Conclusions

Self-Test

Glossary

PDF of this tutorial

The network office is packet-based, distributed, reliable, manageable, and flexible. It distributes the services of the CO throughout the network. The network office enables service providers to move beyond low-margin commodity services into a more profitable arena of augmented and specialized services targeted at new and emerging markets. To make this happen, softswitch vendors are merging new and legacy networks, creating an innovative new network infrastructure.

Proprietary class switches are replaced by a new system with three distinct layers:

1. Services
2. Call control
3. Media devices

This open and layered approach is at the core of the network office.

The term softswitch is often used ambiguously, but for the purpose of this tutorial, softswitch represents the call control layer and does not include the media devices or application servers.

Every component of the network office must meet stringent high-availability standards. Because of the distributed nature of the network office, special considerations and new designs are needed for its elements, including softswitches, application servers, and media devices.

Figure 1. Traditional and Next-Generation Architectures