RFC 5189 · PROPOSED STANDARD · 2008

Middlebox Communication Protocol Semantics

Overview

RFC 5189, “Middlebox Communication Protocol Semantics”, is a Proposed Standard document published in March 2008 by M. Stiemerling, J. Quittek, T. Taylor. It obsoletes RFC 3989. The canonical text is published by the RFC Editor.

Abstract

This document specifies semantics for a Middlebox Communication (MIDCOM) protocol to be used by MIDCOM agents for interacting with middleboxes such as firewalls and Network Address Translators (NATs). The semantics discussion does not include any specification of a concrete syntax or a transport protocol. However, a concrete protocol is expected to implement the specified semantics or, more likely, a superset of it. The MIDCOM protocol semantics is derived from the MIDCOM requirements, from the MIDCOM framework, and from working group decisions. This document obsoletes RFC 3989. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 5189 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 3989
Other RFCs from 2008

Who Is Online

In total there are 273 users online: 0 registered, 266 guests and 7 bots.

Most users ever online was 1,226 on 13 Jun 2026, 3:56 am.

Bots: AhrefsBot Applebot Baiduspider Facebook Other Bot Other Crawler SemrushBot

Users active in the past 15 minutes. Total registered members: 354