The subsystem that provides program-to-program communication with IMS／VS, CICS／VS,TSO,VM,or system application programs using 3270 BSC protocols, and provides support for the BSC portion of the 3270 Device Emulation Feature.; 提供给IMS／VS, CICS／VS, TSO, VM或使用3270 BSC协议的系统应用程序的程序-程序 通信功能,并为3270设备仿真软件的BSC部分提供支持的子系统。