ChorusOS 5.0 Features and Architecture Overview

Chapter 1 Introduction to the ChorusOS 5.0 Operating System

This chapter provides a brief introduction to the ChorusOS operating system, describing its purpose, architecture, the types of target supported, and the enhancements added in version 5.0.

What is the ChorusOS Operating System?

The ChorusOS operating system is a highly scalable and reliable embedded operating system that has established itself among top telecommunications suppliers. The ChorusOS operating system is used in public switches and PBXs, as well as within access networks, cross-connect switches, voice-mail systems, cellular base stations, web-phones, and cellular telephones.

The Sun Embedded Workshop^TM software provides a development environment with the necessary tools to build and deploy the ChorusOS operating system on a telecommunications platform. The ChorusOS operating system is the embedded foundation for Sun's Service-Driven Network. Offering high service availability, complete hardware and software integration, management capabilities and Java^TM technology support dedicated to telecom needs, the ChorusOS operating system allows the dynamic and cost-efficient deployment of new features and applications while maintaining the reliability and functionality of existing networks.

The ChorusOS operating system supports third-party protocol stacks, legacy applications, and applications based on real-time and Java technology, on a single hardware platform.

Component-Based Architecture

The ChorusOS operating system can be tuned very finely to meet the requirements of a given application or environment. The core executive component is always present in an instance of the ChorusOS operating system. Optional features are implemented as components that can be added to, or removed from, an instance of the ChorusOS operating system.

Each API function in the ChorusOS operating system is contained in one or more of the configurable components. As long as at least one of these components is configured into a given instance of the operating system, the function is available. Some library functions are independent of any specific component and are always available.

The optional ChorusOS operating system components are listed in Appendix A, Optional ChorusOS Operating System Components.

Supported Target Families

ChorusOS 5.0 runs over Solaris operating environments, and supports the following targets:

UltraSPARC II (CP1500 and CP20x0)
Intel x86, Pentium
Motorola PowerPC 750 and 74x0 processor family (mpc7xx)
Motorola PowerQUICC I (mpc8xx) and PowerQUICC II (mpc8260) microcontrollers

What's New in 5.0?

The following new features have been added in release 5.0 of the ChorusOS operating system, with an emphasis given to enhancing the high availability and real time services:

Table 1-1 New Features in ChorusOS 5.0


Feature	Description
Black Box	To provide enhanced tracking of system failures.
IPv6	IPv6 base services and commands.
NTP	Network Time Protocol
POSIX real-time API	Including Portable Operating System Interface (POSIX) signals, real-time signals, and process management to complement the existing ChorusOS API, providing a standard, easy migration of UNIX code and bringing the ChorusOS operating system closer to the Solaris operating environment.
Shared Libraries	To extend the existing dynamic libraries feature.
System Events	To notify user-level applications of events in the system or the drivers.
System Instrumentation	System resource instrumentation (with counters and gauges) to control resource usage and anticipate possible over-use or starvation.
System Logging	To provide further logging facilities.
Watchdog Timer Protection	To monitor the system and take action in case of failure.

These new features are covered in more detail in Chapter 2, Architecture and Benefits of the ChorusOS Operating System and Chapter 3, ChorusOS Operating System Features in this overview.