Testing Operations and Maintenance (OAM) Implementations for ATM Application Note 
Size: 896 KB
Date: May 2000

If required, Download Acrobat Reader to view this file.

ATM is being rapidly deployed into the backbones of both corporate and public networks. The backbone is a mission-critical area which demands low downtimes and performance guarantees.

To assist with these critical functions, the International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) defined the Operations and Maintenance (OAM) protocol. This protocol provides for in-service fault detection, fault localization, and performance monitoring for ATM networks. To optimize your network's performance, OAM should become an integral component of an overall ATM network monitoring and network management strategy.

Networks constructed with equipment from multiple vendors require non-proprietary network monitoring strategies to provide a stable base upon which to construct a reliable network. OAM provides a key building block for this base, by defining standardized data elements which are sent within the user data stream to provide particular information about a network and its elements. For every virtual-path or virtual circuit connection OAM can provide the following:

• fault detection
• fault localization
• performance monitoring

OAM provides a standardized method for in-service network monitoring and fault management. It offers automatic fault detection, and when faults are found, other features of OAM may be used to further isolate that fault. Thus, network managers using OAM can reduce their network's downtime.

OAM also offers performance monitoring which is crucial to the reliable transport of voice and video traffic signals which require a guaranteed quality-of-service (QoS).

This application note begins with a discussion of the features of OAM and the operation of the protocol. Then test strategies for validating OAM implementations are presented.