The access method, VTAM®, provides an interface that enables terminals and TSO/E to communicate.

If your installation uses VTAM, you must write a procedure for starting TSO/VTAM, and you must use VTAM APPL definition statements to define the TSO/E application and to define the terminals from which users will be allowed to use TSO/E. In addition, because VTAM does not recognize the TSO/E LOGON command defined in you must define the LOGON command to VTAM. For details about defining TSO/E to VTAM, see Defining and customizing TSO/VTAM and TSO/TCAM time sharing.