What is OTE (Open Transaction Environment)?
Task Control Block
The open transaction environment (OTE) function was added to CICS Transaction Server for OS/390, Version 1 Release 3 and later versions.
In earlier releases of CICS, CICS ran all user transactions under a single z/OS TCB, the CICS quasi-reentrant (QR) TCB. Direct invocation of other services outside the scope of the CICS permitted interfaces could interfere with the use by CICS of the QR TCB. In particular, requests that resulted in the suspension ("blocking") of the QR TCB, which happens when an MVS wait is issued, would cause all CICS tasks to wait. For example, some services provided by DB2, MVS, UNIX® System Services, or TCP/IP, might result in TCB blocking.
