UDPlike

UDPlike is a class of transport-layer approaches that preserve UDP's datagram-based API while providing additional features typically associated with reliable transports. It is not a single standard but a design concept used to describe systems that aim to blend UDP's simplicity and low overhead with optional guarantees.

In practice, UDPlike can be implemented as a user-space library or kernel module. Applications transmit and receive datagrams using familiar UDP sockets, with the possibility to enable reliability, ordering, and congestion control on a per-message basis. In best-effort mode, UDPlike behaves like UDP; in reliable mode, it adds sequence numbers, acknowledgments, retransmissions, and potential buffering to ensure delivery, while still preserving message boundaries.

It supports optional in-order delivery, partial ordering, and fragmentation reassembly; can implement loss detection with timeouts and NACKs; may include path MTU discovery and congestion-control algorithms.

Intended use cases include real-time applications that require low latency but can tolerate some reliability, such as online gaming, live streaming, telemetry, and microservice communication.

Security considerations include susceptibility to spoofing and amplification unless protected by encryption at the application layer or datagram security (e.g., DTLS). Interoperability depends on mutual support of the UDPlike library across endpoints; it remains non-standard.

UDPlike stands in contrast to UDP proper and to fully connection-oriented protocols; it shares some conceptual space with protocols like QUIC, which run over UDP but implement reliability at the transport layer. No universal specification defines UDPlike.