What is protocol¶
Overview¶
A protocol is a set of rules and standards that define how data is exchanged between devices or systems.
For example, in technology landscape
| Protocol | Description |
|---|---|
| HTTP (HyperText Transfer Protocol) | Used for web browsing |
| TCP/IP (Transmission Control Protocol / Internet Protocol) | Core protocols of the internet |
| FTP (File Transfer Protocol) | Used to transfer files between computers |
| Bluetooth Protocol | Defines how devices connect wirelessly |
| Email Protocols | Like SMTP, IMAP, and POP3 for sending and receiving emails |
Protocols are established by the following entities:
Standards Organizations:
These are official bodies that define and publish protocols used worldwide.
- IETF (Internet Engineering Task Force) – Defines internet protocols like TCP, IP, HTTP, and DNS.
- W3C (World Wide Web Consortium) – Creates web standards like HTML, CSS, and WebAuthn.
- ISO (International Organization for Standardization) – Publishes global standards across industries.
- ITU (International Telecommunication Union) – Sets telecom and radio communication protocols.
- IEEE (Institute of Electrical and Electronics Engineers) – Defines hardware and networking protocols like Wi-Fi (802.11).
**Industry Alliances & Foundations**L
Groups of companies or experts collaborate to create specialized protocols.
- OpenID Foundation – Develops identity protocols like OpenID Connect and OpenID4VP.
- Hyperledger Foundation – Creates blockchain and identity frameworks including Aries and Indy.
- FIDO Alliance – Focuses on authentication protocols like FIDO2 and WebAuthn.
Companies & Developers:
Sometimes, protocols start as proprietary or open-source projects.
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Google, Microsoft, Apple, Meta – Often create internal or public-facing protocols for APIs, messaging, or identity.
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Open-source communities – Develop protocols collaboratively (e.g., Matrix for decentralized messaging).
How Protocols Become Standards
- Drafting – Experts write a proposal (often called a “spec”).
- Review & Testing – Community or organization reviews, tests, and revises.
- Publication – Final version is published as a standard (e.g., RFC for IETF).
- Adoption – Developers and companies implement it in software and hardware.
How to read, understand, and take notes on any protocol specification¶
To read and understand a protocol specification:
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Begin by reading the abstract or introduction to grasp the protocol's purpose and scope.
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Identify the key entities involved, such as clients, servers, and issuers, and understand their roles and responsibilities.
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Follow the sequence of messages exchanged between entities, noting the conditions and constraints that apply to each step.
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Study the data formats used to represent information, such as JSON, XML, or JWT, and understand their structure and syntax.
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Analyze the transport and security layers used to protect data in transit, including encryption, authentication, and access control mechanisms.
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Examine the error handling mechanisms in place, including error codes, fallback procedures, and retry policies.
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Clarify the compliance and extension rules, including mandatory and optional components, and understand how they impact the protocol's behavior.