httptcp

HTTP over TCP (httptcp) is the traditional method for delivering Hypertext Transfer Protocol messages using the Transmission Control Protocol as the transport layer. It underpins most basic web traffic, and is the default for HTTP/1.0 and HTTP/1.1. When used with TLS, it is commonly referred to as HTTPS.

Operation: The client opens a TCP connection to the server; after the three-way handshake, HTTP request/response exchange occurs over the established stream. TCP guarantees reliable, in-order delivery and provides congestion and flow control.

Performance: TCP's connection-oriented nature introduces latency, especially in the initial handshake and TLS negotiation for HTTPS. HTTP/1.1 introduced persistent connections to reduce handshakes; but head-of-line blocking at the TCP level can limit parallelism. HTTP/2 mitigates this via multiplexing over a single TCP connection, though still subject to TCP's ordering; HTTP/3 moves to QUIC to avoid TCP head-of-line blocking.

Security and deployment: HTTPS uses TLS; standard ports 80 and 443; proxies, reverse proxies, and content delivery networks (CDNs) deploy httptcp in various architectures; TLS termination often occurs at edge devices; HTTP headers and caching semantics remain part of the protocol suite.