About justprotocols

Our Mission

justprotocols exists to make network and communication protocols accessible to everyone. Whether you are a seasoned engineer debugging a production issue, a student preparing for a networking exam, or just someone curious about how the internet works, our goal is to give you clear, visual, and practical explanations that get straight to the point.

Why We Built This

Protocol documentation is often buried in dense RFCs, scattered across vendor-specific guides, or hidden behind paywalls. We experienced this firsthand while working with industrial protocols like Modbus and PROFINET, where finding a simple explanation of a frame structure meant digging through hundreds of pages of specifications.

We built justprotocols to be the resource we wished existed: one place where you can quickly understand how a protocol works, see its packet structure in a clear diagram, and use free tools to parse and debug real-world data.

What We Offer

  • Protocol guides: In-depth explanations of over 35 protocols spanning transport, application, security, and industrial categories. Each guide includes visual diagrams, packet structure breakdowns, hex examples, and comparison tables.
  • Interactive tools: Browser-based utilities like Modbus parsers, a subnet calculator, hex converter, JWT decoder, and more. All tools run entirely in your browser, so your data never leaves your device.
  • Cheat sheets: Downloadable visual reference charts for topics like common ports, the OSI model, subnet masks, HTTP status codes, and the ASCII table.

Our Approach

Every protocol guide follows a consistent structure so you always know where to find the information you need. We lead with a plain language overview, follow with visual diagrams showing how the protocol works in practice, break down the exact byte-level structure of packets and frames, and finish with real-world examples and frequently asked questions.

We reference official RFCs and specification documents throughout our guides, and we update content as protocols evolve and new versions are released.

Get in Touch

Have a suggestion, found an error, or want to request a protocol guide? We would love to hear from you. Visit our contact page to get in touch.