The Transmission Control Protocol (TCP) and the Internet Protocol (IP) is a protocol suite that allows communications in a network. IPv4 and IPv6 are supported for TCP/IP. See z/OS Communications Server: IPv6 Network and Application Design Guide for more information about the IPv6 protocol in z/OS® Communication Server. On z/OS, the Communications Server provides support for TCP/IP. For information about configuring TCP/IP, see:

• z/OS Communications Server: IP Configuration Guide
• z/OS Communications Server: IP Configuration Reference

You need to perform the following tasks to set up your RRSF network to use TCP/IP:

• Protect the RRSF listener port. For information, see Protecting the RRSF listener port.
• Set up AT/TLS. For information, see Setting up AT-TLS.
• Prevent RACF® from trying to establish connections before the AT-TLS policy is available. For information, see Stack initialization protection.
• Give the RACF subsystem address space access to the TCP/IP stack. For information, see Stack access control.
• Allow the RACF subsystem address space to use z/OS UNIX socket APIs. For information, see Allowing the subsystem address space to use z/OS UNIX socket APIs.