The Multi-Level Secure characteristics of XOmail make it suitable as a secure messaging gateway (“Mail Guard”) between networks with different security characteristics. The X.400 Mail Guard variant was MLS-certified in June 2000 and is a proven solution used by e.g. many NATO-led operations.

The off-the-shelf configuration is prepared for Microsoft Exchange^® with a built-in X.400 Connector as the e-mail servers and Microsoft Outlook^® as the Mail Clients.