Inter-MUD protocol

I3

InterMUD 3

In use today Documented current use Legacy

A major LPC-oriented router network carrying channels, tells, mudlists, services, and out-of-band traffic.

Protocol overview

First seen: 1990s
Present-day status: In use today
In use today?: Yes, with documented current use.
Legacy?: Yes. It may still matter for compatibility or historical systems.
Layer: Inter-MUD protocol
Transport: TCP connections to synchronized routers using LPC data
Research validated: 2026-08-29

Current use and fit

One of the strongest surviving traditional inter-MUD architectures.

Implementation essentials

Encode and validate the six-field packet prefix and packet-specific remainder.
Apply TTL and router synchronization rules.
Put the network behind an inter-MUD service interface.

Compatibility and safety notes

LPC-style payloads complicate non-LPC implementations.
Routers and remote MUDs are separate trust domains.

Original specifications and sources

MUD Standards I3 specification Preservation

Where an original site has disappeared, a preservation archive is linked and identified as such. MUDVerse does not claim authorship of the original protocol.