IBM Z alongside, on the same physical system, to provide another 64-bit application environment that can access and extend z/VSE applications and data via Hipersockets using a wide variety of middleware. CICS, one of the most popular enterprise transaction processing systems, is extremely popular among VSEn users and now implements recent innovations such as Web services. Db2 is also available and popular. Device support VSEn can use ECKD, FBA and SCSI devices. Fibre Channel access to SCSI storage devices was initially available on z/VSE 3.1 on a limited basis (including on IBM's Enterprise Storage Server (ESS), IBM System Storage DS8000, DS6000 series), but the limitations disappeared with 4.2 (thus including IBM Storwize V7000, V5000, V3700 and V9000). See also z/OS z/TPF z/VM History of IBM mainframe operating systems#DOS/VS History of IBM mainframe operating systems References External links VSEn website IBM mainframe operating systems