Avaya a500 Mode D'Emploi

Cajun A500 ATM Switch Overview

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Cajun A500 ATM Switch User Guide

Unlike most system software, a software component is not wired down to a piece of 

hardware. It makes no assumptions about the execution/target environment. At startup, 

each software component is configured by reading a user-defined table containing both 

hardware and application parameters. Every component implements a logical collection 

of system calls. To the application developer, system calls appear as re-entrant C 

functions that can be called from an application. Any combination of components can be 

incorporated into a system to match your real-time design requirements. The 

pSOSystem operating system includes the following components:

U pSOS+ Real-time Multi-Tasking Kernel - A field-proven, multi-tasking kernel 

that provides an efficient mechanism for coordinating the activities of your 

real-time system.

U pSOS+m Multiprocessor Multi-Tasking Kernel - Extends the pSOS+ feature 

set to operate across multiple, tightly-coupled or distributed processors.

U pNA+ TCP/IP Network Manager - A complete TCP/IP implementation, 

including gateway routing, UDP, ARP, and ICMP protocols. It uses a standard socket 

interface that includes stream, datagram, and raw sockets.

U pRPC+ Remote Procedure Call (RPC) Library - Offers SUN

™

-compatible RPC 

and XDR services and enables you to build distributed applications using the 

familiar C procedure paradigm.

U pREPC+ ANSI C Standard Library - Provides familiar ANSI C run-time 

functions such as printf(), scanf(), etc. in the target environment.

Clock Synchronization

The Cajun A500 has the ability to synchronize the clock reference being used for all of its 

OC-3c, OC-12c, and T3/E3 ports to an external reference. The external reference can be 

any of its OC-3c, OC-12c, and T3/E3 ports in its chassis, from an T1/E1 circuit (used 

specifically for clocking purposes) connected to the SWP board, or from the T3/E3 board.

You select and prioritize four external references (two OC-3c/OC-12c, or T3/E3 ports 

and two T1/E1 ports) for use as the clock reference for the Cajun A500. The external 

source with the highest priority is used as the external source that the Cajun A500 locks 

to. If the selected source goes bad, an external source with the next highest priority is 

used. If all the external references go bad, the Cajun A500 generates timing using a 

holdover mode. In holdover mode, the Cajun A500 regenerates the timing of the last 

source it was locked to and uses this timing as its reference source. If there was not a 

good last source, the Cajun A500 enters free mode, generating timing from an on-board 

oscillator.