High-speed data plane and network functions virtualization by vectorizing packet processing.

In the last decade, a number of frameworks started to appear that implement, directly in user-space with kernel-bypass mode, high-speed software data plane functionalities on commodity hardware. This may be the key to replace specific hardware-based middleboxes with custom pieces of software, as advocated by the recent Network Function Virtualization (NFV) paradigm. Vector Packet Processor (VPP) is one of such frameworks, representing an interesting point in the design space in that it offers: (i) in user-space networking, (ii) the flexibility of a modular router (Click and variants) with (iii) high-speed performance (several millions of packets per second on a single CPU core), achieved through techniques such as batch processing that have become commonplace in high-speed networking stacks (e.g. netmap or DPDK). Similarly to Click, VPP lets users arrange functions as a processing graph, providing a full-blown stack of network functions. However, unlike Click where the whole tree is traversed for each packet, in VPP each traversed node processes all packets in the batch (or vector) before moving to the next node. This design choice enables several code optimizations that greatly improve the achievable throughput. This paper introduces the main VPP concepts and architecture, and experimentally evaluates the impact of its design choices (such as batch packet processing) on its performance.