Parallel processing in network processor architectures

Parallel processing is well established in high-performance computing. Currently, network processors as new emerging, special-purpose processors are targeted at the exploitation of parallelism to meet the requirements in data-plane processing with wire-speed. The achievable level of parallelism is determined by decisions in the architecture design and by the characteristics of the data-plane applications executed. We discuss two basic approaches in parallel processing, namely pipelining and concurrency, which establish basic models for parallel network processor organization. The features and constraints of these models are studied. Using this background some existing network processor architectures are reviewed and characterized regarding their potential in parallel data-plane processing.