Fivebyte

Fivebyte is a compact binary data encoding format designed for resource-constrained environments. It uses five-byte records as the basic unit and aims to minimize overhead while preserving structure, enabling efficient transmission and parsing of structured data in low-bandwidth networks and embedded systems.

Origin and development: The concept gained attention in discussions of lightweight encodings in the mid-2010s. An open specification was released by a collaborative group known as the Fivebyte Consortium in 2017, followed by reference implementations and documentation in multiple programming languages.

Technical characteristics: Each message starts with a fixed five-byte header that conveys the payload type, length, and optional flags. The payload encodes primitives (integers, floats, strings) and composite constructs (arrays, maps) through a compact tag-length-value scheme. Endianness is standardized, and optional integrity checks such as a CRC are defined to ensure data reliability.

Usage and applications: Fivebyte is intended for IoT sensors, telemetry, and other constrained environments where bandwidth and power are at a premium. Implementations exist in several languages, and the format has been used in pilot deployments and academic experiments to compare performance with other binary encodings.

Relation to other formats: Fivebyte sits alongside CBOR, MessagePack, and Protocol Buffers in the space of compact binary encodings. Proponents emphasize its predictability of size, fixed header semantics, and streaming friendliness, while critics point to a relatively small ecosystem and fewer mature tooling options.