Connection Multiplexing (Proxy)

A proxy optimisation technique where many client-side connections are tunnelled through a smaller number of persistent backend connections, reducing the TCP connection establishment overhead on origin servers. Reverse proxies such as Nginx, HAProxy, and Envoy maintain long-lived keep-alive connection pools to backends; each new client request reuses an existing backend connection rather than opening a new one. HTTP/2 multiplexing extends this further by sending multiple request streams over a single TCP connection. gRPC inherently uses HTTP/2 connection multiplexing, making it efficient for high-frequency service-to-service communication.