Traffic Engineering and Control for the Mangement of Service Level Agreements in Packet Networks

The talk considers templates for QoS-centered Service Level Agreements (SLA), and a framework for their real time management in multiservice packet networks. The SLAs are for QoS-assured delivery of aggregate bandwidth from ingress to efress nodes, where the elementary entities are flows or calls of various QoS classes. A SLA monitoring scheme is presented in which revenue is generated by the admission of flows into the network, and penalty incurred when flows are lost in periods when the service provider is not SLA-compliant. In the SLA management scheme proposed here the results of a prior design are used, in conjunction with measurements taken locally at ingress nodes, to classify the loading status of routes as either undersubscribed or oversubscribed. Our resource management is based on Virtual Partitioning and its supporting mechanism of Bandwidth Protection, which aims to carry as much of the offered flows at any time as is compatible with protection of future undersubscribed routes. The effectiveness of SLA management is measured by the robustness in performance in the presence of great diversity in actual traffic conditions. The talk will describe a simulation testbed called D'ARTAGNAN from which numerical results for a case study are presented. The results show that the SLA management scheme is robust, fair and efficient over a broad range of traffic conditions.