How bridge facility virtual terminals are autoinstalled

Bridge facility virtual terminals are defined as LU2 devices. They are created by the 3270 bridge mechanism to support the execution of a CICS® 3270 application in a bridged environment, where all terminal interaction is intercepted and passed to the 3270 bridge mechanism.

The 3270 bridge mechanism uses a model 3270 terminal definition (facilitylike) to build the bridge facility, creating both an eight-byte token to identify it and a four-character terminal identifier, which is used as both TERMID and NETNAME.

For bridge facilities created with the START BREXIT command, the token and name are unique within the region creating the bridge facility, and the TERMID takes the form }AAA, where AAA is an alphabetic sequence that ascends serially.

For bridge facilities created by the link3270 bridge, the token and name are unique across the CICSplex, and the TERMID is of the form AAA}. Uniqueness is achieved by using a shared file to control allocation of names.

Bridge facility terminal names and netnames are normally allocated dynamically by the bridge mechanism, but if the AIBRIDGE system initialization parameter is set to YES, the terminal autoinstall control program is called and can be used to assign installation specific names.