Game, multimedia, consumer and control applications today often demand high performance computing platforms that are able to deliver real-time services while satisfying tight power constraints. Multi-core architectures, supported by on-chip networks, are emerging as scalable solutions to fulfill these requirements. However, the increasing number of concurrent applications running on these platforms and the time-varying nature of the communication requirements give rise to communication delays that are difficult to predict.

We propose a simple and flexible instrumentation of the on-chip network that provides services to the application software for establishing end-to-end communication flows with timing guarantees. We provide a detailed analysis of the delay in a NoC using worm-hole flow control and an algorithm that, given the state of the NoC and a request to route a new real-time flow, establishes a suitable path for the route, if one exists, or rejects the request. We implemented the new protocol in a cycle-accurate simulator to validate the accuracy of the models and the correctness of the path establishment algorithm.