MessageIDlike

MessageIDlike is a descriptive term used in software design to refer to identifiers that resemble a Message-ID in function, rather than a formal standard with a fixed syntax. Values described as MessageIDlike are intended to uniquely identify individual messages or events across systems, enabling reliable tracking, correlation, and deduplication. The concept emphasizes cross-component uniqueness and immutability where a message’s identity should persist beyond the lifetime of any single process.

Key characteristics of MessageIDlike values include global uniqueness, immutability, and an opaque structure that should reveal minimal internal information. They are often generated in a way that mitigates collisions, such as using time-based components combined with randomness or host-derived data. While some implementations adopt a format inspired by the traditional Message-ID (for example, a local part paired with a domain-like suffix and optional angle-bracket notation), actual formats vary by system and are not restricted to any single specification.

Common generation strategies include UUIDs, ULIDs, or custom schemes that mix timestamps with random or node-specific data. In practice, MessageIDlike values are used as message headers or keys for routing, threading conversations, correlating logs, and enabling idempotent processing in distributed architectures. They should be designed to avoid leaking internal topology and to remain stable enough to serve as long-term references.

See also: Message-ID, UUID, GUID, ULID, correlation ID, message header.