___                   __  __  ______  __
 / _ \ _ __   ___ _ __ |  \/  |/ ___\ \/ /
| | | | '_ \ / _ \ '_ \| |\/| | |    \  /
| |_| | |_) |  __/ | | | |  | | |___ /  \
 \___/| .__/ \___|_| |_|_|  |_|\____/_/\_\
      |_|

Project OpenMCX — 3GPP Release 19 MCx services

The project OpenMCX implements 3GPP Release 19 mission-critical services (MCx) for an IP network: the common service core, MCPTT (mission-critical push to talk), MCData (mission-critical data) and MCVideo (mission-critical video). It runs as a set of containers — a SIP core, application servers, common services and clients — and every feature is exercised by automated scenarios in a fresh lab. Off-network (ProSe) operation is outside this build.

This is the standalone edition: one MC system for all three services. What exists only between two MC systems (interconnection, MC gateway servers, migration) is not part of it. The clients are in openmcx-client and MCX Admin in openmcx-admin.

Containerised deployment on Ubuntu 24.04 LTS (default) and Ubuntu 26.04 LTS (building).

Try it: Tutorial 1: MCX over WLAN with the Android app runs the whole system on one computer from the Docker Hub images, with two Android phones on the same Wi-Fi (all tutorials).

It is not an interoperability-certified implementation: see the limitations.

Services

MCPTT

• Prearranged, chat, broadcast and ad hoc group calls, with floor control and queueing
• Private calls (automatic, manual and forced commencement, with or without floor control), first-to-answer, ambient listening and remotely initiated calls
• Emergency and imminent-peril calls, emergency alerts, priority pre-emption
• Call-back, transfer and forwarding; functional aliases; regroups
• Location reporting and requests, emergency alert and group geographic areas
• End-to-end protected media (GMK and PCK) and protected XML signalling

MCData

• Short data (SDS) over the signalling and media planes, one-to-one, group and ad hoc
• File distribution over HTTP and over the media plane, with disposition notifications
• Emergency and imminent-peril communications, group emergency alerts
• IP connectivity, enhanced status, communication release, functional aliases
• Message store with notification channels, location
• End-to-end protected payloads, signalling and XML

MCVideo

• Prearranged, chat and ad hoc group calls, with transmission control (queueing, revocation, implicit request) and reception control
• Private calls with and without transmission control, in every commencement mode
• Emergency and imminent-peril calls with pre-emptive transmission, emergency alerts, ad hoc group emergency alerts
• Video pull and push, one-to-one and to or from the server with its recording; ambient viewing; remote transmission
• Regroups, functional aliases, remote group selection and location
• End-to-end protected video (GMK and PCK), protected transmission control and protected XML signalling

Common services

• Identity (OIDC), group management (XCAP and subscriptions), configuration, location and key management
• Separate participating and controlling servers within one MC system

Documentation

• Feature list: what each service supports and how it is verified
• Using the lab: build, run, client commands, verification and SIP debugging
• Developer guide: architecture, source tree, request flow, state machines, testing and workflow
• Tutorials: end-to-end and unit-test tutorials, with reference captures
• 3GPP correction candidates: Release 19, AI-assisted review, awaiting expert confirmation
• Limitations: what the present edition does not include, and the limits of what it does

Licence

Project OpenMCX is licensed under the GNU Affero General Public License v3.0 or later. Third-party software and its licences: NOTICE.

Contact: contact@openmcx.com