virtual telecommunications access method การใช้

IBM introduced VTAM ( Virtual Telecommunications Access Method ) with the System / 370.
ACF / VTAM ( Advanced Communication Function / Virtual Telecommunications Access Method ) was introduced in 1976 and was provided for a licence fee.
"' Virtual Telecommunications Access Method "'( "'VTAM "') is the IBM subsystem that implements Systems Network Architecture ( SNA ) for mainframe environments.
A limited version of ACF / VTAM known as "'ACF / VTAME "'( Advanced Communications Function for the Virtual Telecommunications Access Method Entry ) was made available for DOS / VSE systems running on the IBM 4300.
TCAM's name suggests that IBM hoped it would become the standard access method for data communications, but in fact TCAM in OS / VS2 was used almost entirely for TSO and was largely superseded by Virtual Telecommunications Access Method ( VTAM ) in the mid-to-late 1970s.