α-Channel: A Network Framework to Support Application Real-Time Performance Guarantees

The current challenge in designing an integrated packet switched network is to support real-time applications with a wide variety of quality of service requirements, in terms of expected throughput, acceptable levels of packet loss, and bounded network packet delay. Often, these applications require that the network guarantee their qualities of service. Providing support for guaranteed real-time performance requirements in an integrated network is the focus of this paper. We propose a framework to support performance requirements for real-time applications. This framework is based on a network-level abstraction called a-channel. An a channel represents a simplex end-to-end communication channel characterized by a set of application-specific real-time performance values. Applications treat the a-channel as an end-to-end abstraction, and specify their required performance characteristics in terms of the maximum end-to-end packet delay, the maximum number of packets that can be sent within that delay, and the on-time reliability. Based on specified parameters, the network verifies that it can guarantee the performance of the channel under any conditions baring hardware failures. The approach the framework uses to verify the feasibility of accepting an a-channel and the characteristics of the run-time environment to guarantee the application's performance requirements are described. The results of a simulation experiment implementing the basic functionalities of the proposed scheme are also presented.