Concise Binary Object Representation (CBOR)
CBOR is the binary envelope behind COSE cryptographic messages and many constrained-device protocols. Typed length-prefixed encoding without a schema — unlike Protobuf.
What It Defines
Binary serialization format with self-describing typed values: major types (unsigned/negative int, byte string, text string, array, map, tag, float/simple). Compact alternative to JSON; used in COSE (WebAuthn), DNS, IoT, and blockchain. Often compared to MessagePack.
Canonical (Normative)
Convenient (Practical)
The canonical publication point for finalized RFCs. If a protocol is standardized as an RFC, the RFC Editor text is the normative final reference. Published by the IETF, IRTF, IAB, and independent stream.
Related Specs
JSON is the lingua franca of web APIs. RFC 8259 is short and worth reading once — it clarifies edge cases around numbers, encoding, and trailing commas.
MessagePack is a practical middle ground when JSON is too large and Protobuf is too rigid. Know tag-byte structure for debugging wire captures.
Protobuf is the wire format for gRPC and many high-performance internal APIs. Schemas are also used for event/message contracts in Kafka/pubsub systems.
Passkeys are the modern replacement for passwords. WebAuthn is the browser API. Every new auth system should evaluate it for primary or MFA flow.