Smart box architecture: a hybrid solution for IP QoS provisioning

This work proposes a hybrid solution, called the smart box architecture (SBoX), that provides quality of service (QoS) in internet protocol (IP)-based networks. SBoX architecture consists of SBoX servers, which are located at the network boundary, and SBoX routers, which are add-on label switching routers (LSR), which are located at interior network nodes. This approach combines the advantages of three existing technologies: integrated services (Intserv), differentiated services (Diffserv), and multi-protocol label su itching (MPLS). SBoX aggregates traffic in three levels: commodity-flows, macro-flows and micro-flows. Commodity-flows aggregate flow between every pair of edge points. The packets of the same commodity-flow are marked by an MPLS label. Commodity-flows are composed of macro-flows, which aggregate the traffic of a particular enterprise. Macro-flows are associated with an explicit service level agreement (SLA), which is offered to users. Macro-Rows are composed of micro-flows, which are the traffic associated with a particular individual in an enterprise or a particular application. SBoX servers provide Diffserv like SLA to users, and use class-based queuing (CBQ) with a hierarchy of how aggregation. SBoX servers manage macro-flows and commodity-flows only, and leave the management of micro-flows to the enterprise/users which signed the SLA for the macro-flow. SBoX routers perform MPLS routing of commodity-flows in interior network nodes. SBoX routers can be combined with existing best-effort routers to provide QoS in a network that lacks end-to-end deployment of LSRs. This paper describes the SBoX architecture and its operation in detail. It also reports experimental results obtained on a prototype network. The results indicate that the SBoX architecture can indeed provide guaranteed performance in a congested network, and that SBoX routers can be combined with commodity best-effort routers to enable QoS in a heterogeneous network. (C) 2001 Elsevier Science B.V. Al rights reserved.