QoS Parameters to Network Performance Metrics Mapping for SLA Monitoring

Service Level Agreement (SLA) is a formal negotiated agreement between a service provider and a customer. The service level management (SLM) is the integrated management of all functionalities in the SLA life cycle. When a customer orders a service from a service provider, an SLA is negotiated and then a contract is made. In the SLA contract, QoS parameters that specify the quality level of service that the service provider will guarantee are included. The service provider must perform SLA monitoring to verify whether the offered service is meeting the QoS parameters specified in the SLA. SLA monitoring involves monitoring the performance status of the offered service and provide relevant information to the service level management system. In order for the service level management system to verify whether the specified QoS parameters are being met, the system must gather performance data from the underlying network performance monitoring system and map such data to the QoS parameters. In this paper, we propose a formal mapping mechanism between QoS parameters in SLA and the network performance metrics. Although we focus on the network access service (e.g., leased-line service, xDSL service, VPN service) in this paper, we believe that our mapping mechanism can be easily used in SLA monitoring of other services (such as application, server hosting, contents). We also propose a general SLA monitoring system architecture that can be used to monitor service levels for various services offered by network, Internet and application service providers. Finally we present how our SLA monitoring system architecture can be used for SLA monitoring of IP backbone network service.