Disclosed herein are various systems, apparatuses, software, and methods relating to data diode-TCP proxy with a User Datagram Protocol (UDP) across a wide area network (WAN) providing a WAN data diode using a uni-directional semantics protocol, providing a set of data diode proxies in either end of a point-to-point WAN link, providing a symmetric key encryption semantics to extend the WAN data diode securely across a WAN that is specified, wherein the symmetric key encryption semantics are implemented through the set of data diode proxies on either end of the point-to-point WAN link, employing a unidirectional protocol in communication transmitted using the WAN and, with data diode proxies, terminating one or more data channels on either end of the point-to-point WAN link or transporting a requisite information across the WAN over the uni-directional protocol.