8 Essential Network Protocols Every Developer Should Know

Network Protocol Overview

Network protocols define standardized methods for data exchange between computers on a network.

Eight commonly used protocols

HTTP (Hypertext Transfer Protocol) – the foundational client‑server protocol used to request and deliver HTML pages, CSS, JavaScript, images and other resources. It operates over TCP (port 80) and follows a request‑response model.

HTTP/3 – the latest revision of HTTP that runs on QUIC, a transport protocol built on UDP. QUIC provides multiplexed streams, reduced connection‑setup latency, and built‑in encryption, making HTTP/3 especially suitable for latency‑sensitive applications such as virtual reality or real‑time streaming.

HTTPS (HTTP Secure) – HTTP layered with TLS/SSL encryption. It authenticates the server (and optionally the client) and protects confidentiality and integrity of the exchanged data. Default port is 443.

WebSocket – a protocol that upgrades an HTTP connection to a persistent, full‑duplex TCP channel (RFC 6455). It enables servers to push data to browsers without repeated polling, commonly used in online gaming, financial tickers, and chat applications.

TCP (Transmission Control Protocol) – a reliable, connection‑oriented transport protocol that guarantees ordered delivery, retransmission of lost packets, and flow control. Most application‑layer protocols (HTTP, SMTP, FTP, etc.) rely on TCP.

UDP (User Datagram Protocol) – a connectionless transport that sends datagrams without establishing a session or guaranteeing delivery. Its low overhead makes it ideal for time‑critical traffic such as VoIP, video streaming, and online gaming where occasional loss is acceptable.

SMTP (Simple Mail Transfer Protocol) – the standard protocol for sending email between mail servers. It operates over TCP (port 25, 587 for submission) and defines commands such as HELO, MAIL FROM, RCPT TO, DATA.

FTP (File Transfer Protocol) – a protocol for transferring files between a client and a server. It uses separate control (port 21) and data connections (active or passive mode) and supports commands for directory navigation, file upload/download, and authentication.

These protocols together constitute the core communication stack of the modern Internet.