UDP Datagram Transport

Tags: wire, transport, message-flow

© R.A.Sol

UDP is a single-datagram message-flow transport for fast bounded lookups.

Via: udp+host[:port] (033). Default port: 4777.

Advertised in HELLO or equivalent endpoint greeting metadata as Transport: udp[:port] flow=message.

Supported Commands

UDP is a stricter message-flow subset:

• 🖧GET
• 🖧HEADERS

UDP returns INVALID for 🖧LIST, 🖧INGEST, 🖧STORE, and all other commands.

Protocol

No explicit HELLO round-trip runs on UDP itself. Each exchange is one request datagram and one response datagram.

Request is one endpoint-defined message-flow request envelope (031) in a single UDP datagram.

The HPPR Repository Service envelope is defined in 044.

Response is one datagram: raw packet bytes on success, Null packet on error. Unrecoverable failures produce no response.