A protocol is a standardized set of rules that governs how two systems communicate. It defines how messages are structured, transmitted, and acknowledged across a network. Without protocols, devices made by different manufacturers would not be able to exchange data reliably. Protocols ensure interoperability, security, and predictability across systems ranging from browsers to servers to IoT devices. Each protocol solves specific communication challenges, such as reliable delivery, encryption, or routing. The internet is built on layers of protocols working together to move data globally.
key characteristics
Protocols exist at many layers: low level protocols manage addressing and packet handling, while higher level protocols define request formats and semantic meaning. Examples include TCP for reliable transport, UDP for low latency messaging, and HTTP for web requests. Protocols define fields such as headers, payloads, checksums, and sequence numbers. Tools like network inspectors help developers troubleshoot protocol errors and misconfigurations. Understanding protocols is essential for debugging connectivity issues and designing distributed systems.