Networking Services - XNS - CAE Specification Author:The Open Group This Networking Services (XNS) specification describes the industry-standard open systems interfaces to communication services. These include two APIs to transport-level process-to-process communications: Sockets and XTI. Both Sockets and XTI are specified for use over Internet protocols (TCP, UDP and IP) and ISO Transport protocols. ... more »They also include a set of Internet address resolution interfaces which are commonly used in conjunction with Sockets. XTI support for many other protocols is described in appendices included in this specification. This XNS specification forms part of the Single UNIX Specification, Version 2 (T912) required for the UNIX 98 Brand. It includes revisions to align with the IEEE Standard 1003.1:1990 (Portable Operating System Interface).« less