Minimum Rate Guarantee Without Per-Flow Information

This paper introduces a scalable maxmin flow control protocol which guarantees the minimum rate for each connection-oriented flow without requiring per-flow information. The protocol is called MR-ASAP (Minimum Rate guaranteeing Adaptive Source-link Accounting Protocol). MR-ASAP is an extension of ASAP [Tsa98a, Kim99], the first exact maxmin flow control protocol for best-effort connection-oriented traffic in integrated service networks, without requiring per-flow accounting at the intermediate network node. In the classical maxmin computation, only the maximum rate constraints are considered; in this paper the minimum rate requirements are treated similarly as the maximum rate constraints. Existing protocols that achieve exact maxmin optimality with minimum rate guarantee require per-flow information and complex computation such as sorting of the minimum rates at the switch. By generalizing the concept of constraint, the complex sorting and per-flow accounting required in the existing protocols are avoided. Simulation demonstrates fast convergence to optimality. The convergence of MR-ASAP is also proved analytically.