On this page you'll find a general overview of our XMPP server, M-Link. On other pages in this section, you’ll find information on M-Link’s use of Directory for configuration/authentication, security features, support for wide and local area clustering, operation over constrained/unreliable networks, Federated/Multi-User Chat, Archive & Search, and support for Military Forms using FDP.

M-Link is Isode's Instant Messaging and Presence server based on the XMPP (eXtensible Messaging and Presence Protocol) standard. XMPP is the Open Standard for Instant Messaging and Presence, formalized by the IETF in 2002-2004, and continuously extended through the standards process of the XMPP Standards Foundation.

M-Link is used in both specialised deployments where security, reliability and special functionality are vital and in large public deployments where responsiveness, performance and scalability are paramount. The world's first public XMPP deployment (jabber.org) runs M-Link. Jabber.org is still one of the largest XMPP services with over 300,000 users.

M-Link Security

Isode has incorporated into M-Link features that make it the natural choice for instant messaging and presence in military, intelligence and government deployments. These features include support for security labels according to XEP-0258: Security Labels in XMPP, data confidentiality using TLS and support for SASL authentication, Kerberos authentication and Strong Authentication (based on X.509 Public Key Infrastructure), for client/server and for server/server connections. For more information, please see the page on M-Link Security.


M-Link's scalability and support for both Wide and Local Area Clustering make it the natural choice for deployments supporting large and growing user numbers and concerned about service interruptions due to server or network failure, support for Disaster Recovery and for military organizations needing a survivable deployment. You can read more about this on the M-Link Clustering page.

Support for Disadvantaged Networks

M-Link provides a range of capabilities for operating over networks with low bandwidth, high delay and poor reliability. This includes support for HF Radio and Federated Multi-User Chat (FMUC). For more details see page on support for disadvantaged Networks.

Multi-User Chat (MUC) and Federated MUC

M-Link supports MUC capabilities as set out in XEP-0045: Multi-User Chat and also supports XEP-0289: Federated MUC for Constrained Networks which allows MUC provision to be federated across multiple servers in distributed deployments with poor links between participants. Security Label based controls can be used with both MUC and FMUC. For more details see the M-Link Multi-User Chat page.

Archive & Search

M-Link has extensive archiving capabilities including search of 1:1 and multi-user chat history, export to XML archives and archiving in PDF/A documents, covering requirements up to and including very-long term archiving. End user access to archives is provided using the protocol specified in XEP-0313: Message Archive Management (MAM) for both standard XMPP Clients and web access using XEP-0206: XMPP over BOSH. More information on these capabilities can be found on the M-Link Archive & Search page.

Form Discovery and Publishing (FDP)

M-Link enables flexible forms publishing and distribution using the protocol described in XEP-0346: Form Discovery and Publishing. Forms are important for military operations, and there is often a need to handle forms quickly and share with a large number of users. XMPP based open standard instant messaging is a sensible framework for sharing forms. An overview on M-Link's support for FDP can be found on the Forms Discovery and Publishing page.

Directory for Authentication

M-Link uses Directory to hold user, authentication and group information. M-Link use Isode’s M-Vault directory (included with M-Link) or an existing directory holding account and directory information, such as Active Directory. To read more about this, please see the page on Directory for users, groups and authentication.

Management Tools

M-Link Console is GUI tool that provides full configuration and operational management of M-Link servers and clusters. For more information, please see the page on M-Link Management which also includes information on SNMP monitoring and Web Tools for account management.