Multi-Stream TCP Design
Nicola Zingirian · 2023
The proposed Multi-Stream TCP (MS-TCP) transport protocol challenges the traditional one-to-one relationship between the Transport Control Protocol (TCP) connections and full-duplex streams. This paper explores the feasibility and advantages of allowing a single TCP connection to support multiple streams through distinct sockets, with a focus on enhancing the efficiency of concurrent web transactions. The MS-TCP protocol addresses the increasing demand for efficient utilization of TCP network connections in today’s network interoperation, dominated by HTTP-based transactions, offering a legacy-aware architecture alternative to the disruptive HTTP/3 QUIC solution. By relaxing the strict connection-stream relationship, MS-TCP introduces the concept of “channel”, a single TCP-based connection that can accommodate multiple concurrent streams. The paper presents a detailed examination of the design, architecture, and implementation choices involved in realizing the requirements of MS-TCP. These requirements include adherence to POSIX Standard APIs, seamless integration with existing network middleboxes, mitigation of Head-of-Line (HoL) blocking issues, enabling zero roundtrip time, and skipping the slow-start state when activating new streams.