Definition
Protocols are sets of rules that govern how data is transmitted and received between devices on a network. They define the format, timing, sequencing, and error checking required for successful communication. In practice, protocols act as a common language, ensuring that different systems and applications can understand each other. Understanding protocols is crucial for network administrators and security professionals to design, troubleshoot, and secure network infrastructure. For example, HTTP is the protocol used for transferring web pages between a browser and a web server. Unlike a physical network cable which transmits raw electrical signals, protocols provide the logical structure for data exchange. Knowledge of protocols is fundamental for certifications like CompTIA Security+, Network+, and AWS Certified Solutions Architect Associate.