Nexor Sentinel is a high assurance email guard, built upon an EAL4+ evaluated product and listed on NATO’s NIAPC catalogue. It has been designed to protect organisations by validating that in-bound and out-bound electronic messages conform to the security policy of the protected domain. 

Nexor Sentinel mitigates security breaches that could lead to unauthorised access. Its security functionality ensures that an electronic message can only pass from one domain to the other via a trusted, secured path. All messages are scanned and validated against the defined security policies and non-conformant messages are rejected and quarantined, preventing the potential damage caused by outbound information loss or inbound malicious content. 

Nexor Sentinel has policy enforcing filters for message transport (such as message envelope checks, access control lists, return of content in reports); for message content (including allowed attachment types, dirty word searching); and for message security (message signature, message encryption, signed receipts). 

Nexor Sentinel supports both SMTP and X.400 email messages, and its full message logging provides traceability of communication exchanges to ensure the integrity of the system. Nexor Sentinel products have been deployed worldwide by national defence forces and organisations such as NATO, the UK Ministry of Defence and other international Defence organisations.