P4IX: a concept for P4 programmable data planes at IXPs

ABSTRACTInternet Exchange Points (IXPs) are a crucial part of the Internet's infrastructure. Large IXPs can potentially interconnect thousands of ASes and facilitate the exchange of more than 10 Tbps of traffic during peaks. However, their specific technical requirements (e.g., large Layer-2 domains, complex traffic filtering) are not well addressed by today's networking hardware, as vendors optimize for the ISP market due revenues that are orders of magnitude higher. Software Defined internet eXchanges (SDXes) are a promising solution since they enable tailored hardware and software stacks to satisfy the specific IXP requirements. They combine a high degree of automation with the flexibility to implement value-added services and, thus, may reduce IXP's costs. Since previous work is based on the OpenFlow standard, which was last updated in 2017, we revisit the idea by leveraging the flexibility of P4 networking hardware. We present the P4IX, a technical concept for a generic P4 packet processing pipeline for IXPs. The P4IX concept is built upon a comprehensive requirements analysis: we characterize the IXP landscape and provide first-hand insights of a large IXP operator (more than 1000 well distributed ports). Moreover, we use our insights to critically discuss the P4IX from an operational, technical, and organizational perspective.