A pipeline functional language for stateful packet processing

The evolution of commodity PCs towards multi-core processing platforms equipped with high-speed network interfaces makes them reasonable and cost effective targets for the implementation of generic network functions. In addition, the availability of software accelerated I/O frameworks provides a convenient ground for running a broad variety of applications, from simple software switches to more complex network systems, with near hardware-class performance and the flexibility of a software approach. Most network functions can be implemented by composing a set of elementary operations into processing pipelines to be run on top of multiple processing cores. In this framework, maintaining the flow consistency is crucial to enable stateful operations in the processing pipelines. This paper presents Enif-Lang, a functional language for programming network pipelines specifically targeted at multi-core scenarios. In addition to a large set of functions for generic packet manipulation, filtering, steering and state management, the framework is built upon an abstract model that provides state aware packet splitting to prevent inter-state sharing and enable consistent stateful parallel processing on-top-of multi-core architectures.