A Target-Agnostic Protocol-Independent Interface for the Transport Layer

Abstract: Transport protocols are fundamental to network communications, continuously evolving to meet the demands of new applications, workloads, and network architectures while running in a wide range of execution environments (a.k.a targets). We argue that this diversity across protocols and targets calls for a high-level, target-agnostic programming abstraction for the transport layer. Specifically, we propose to specify transport protocols as high-level programs that take an event and flow state as input, and using constrained C-like constructs, produce the updated state along with target-agnostic instructions for key transport operations such as data reassembly, packet generation and scheduling, and timer manipulations. We show the benefits of our high-level transport programs by developing multiple transport protocols in our programming framework called TINF, developing two TINF- compliant backends, one in DPDK and one in Linux eXpress DataPath, and deploying TINF programs for multiple protocols across both backends. Inspired by the benefits unlocked by L2/L3 packet-processing languages like P4, we believe target-agnostic transport programs can reduce the development effort for transport protocols, enable automated analysis and formal verification of the transport layer, and further research in programmable targets for transport protocols.