CBOR

Concise Binary Object Representation (CBOR) is a data serialization format designed to be small, fast to parse, and easy to implement on devices with limited memory and bandwidth. It encodes a wide range of data structures in a compact binary form, offering a practical alternative to text-based formats such as JSON while preserving rich data types. CBOR was standardized by the Internet Engineering Task Force and is widely used in IoT and other constrained environments.

CBOR data is organized into major types encoded in the initial bits of each item. Major types cover unsigned integers, negative integers, byte strings, text strings, arrays, maps, tags, and simple values such as booleans, null, and undefined, as well as floating-point numbers. Lengths and values are carried in an information field that can be definite or indefinite; tags provide semantic meaning for specialized data like dates or large numbers. The format is binary and self-describing, and deterministic encoding is achievable in canonical forms.

CDDL (Concise Data Definition Language) provides a textual schema language for CBOR data structures, enabling validation and documentation of CBOR payloads. The CBOR ecosystem also includes security-related profiles such as COSE (CBOR Object Signing and Encryption) that use CBOR for cryptographic data. Implementations exist in many programming languages and platforms, making CBOR a common choice for interprocess communication and data interchange in resource-constrained networks.

Overall, CBOR's compactness, extensible type system with tags, and support for streaming make it well suited for IoT, RESTful protocols, and messaging systems. It remains important to consider tooling and interoperability, especially when relying on optional features such as indefinite-length items or specific tag usage. CBOR complements JSON by providing a binary representation that preserves structure while reducing overhead.