Network services provide the capabilities and mechanisms to support distributed applications requiring data access and applications interoperability in heterogeneous, networked environments. These services include the following:

• Data communication includes API and protocol specifications for reliable, transparent, end-to-end data transmission across communications networks.
• Transparent file access to available files located anywhere in a heterogeneous network.
• Personal/micro computer support for interoperability with systems based on other operating systems, particularly microcomputer operating systems, which may not be formally specified in a national or international standard.
• Remote Procedure Call services include specifications for extending the local procedure call to a distributed environment.
• Network security services include access, authentication, confidentiality, integrity, and non-repudiation controls and management of communications between senders and receivers of information in a network.