SLA and Network Monitoring

This chapter discusses the technologies and techniques available for SLA and network monitoring in QOS-enabled IP networks. There are two main approaches, which are generally used in concert to monitor the performance of a QOS-enable network service in order to determine whether SLAs have been or can be met: • Passive network monitoring . With passive network monitoring, network devices record statistics on network traffic, which can provide an indication of the status at a particular network element. Periodic polling is typically used to gather this data for reporting and analysis. This is a micromeasure which looks at each device in isolation; by looking at multiple network elements an aggregate view of the status of a network service may be deduced. Passive network monitoring does not require any additional traffic be used for measurement purposes.