How do you say hi or hello or howdy to mainframe? You know how to talk to your Personal Computer (PC). You start your PC, login with user name and password on login screen and you enter the PC. Once you logged on to PC, you will interact with PC various ways. You use your mouse, keyboard, stylus or your finger to work with various applications that interact with operating system on PC. Now lets look at how a user interacts with mainframe.
Mainframe computers are large, multi-processor computing devices able to perform thousands of tasks every second. These mainframes usually reside at remote data centers. z/OS is widely used operating system on mainframe. To talk to these remote mainframes, 3270 display devices (aka dumb teerminal) or TN3270 emulator (aka green screens) running on PC are used. Web based applications to interact mainframe are also beginning to get popular that suits well with younger generations.
A system programmer, application programmer or administration needs to interact with mainframe system reguraly. Mainframe provides following interfaces to access it: Time Sharing Option (TSO), Interactive System Productivity Facility(ISPF) and UNIX Shell.
With TSO, users can log on and interactively share mainframes resources. Once logged in, a TSO also provides basic command prompt interface that users specifies commands to interact with mainframe. This is called native TSO mode and is similar DOS prompt of windows. However most installation, automatically switch to ISPF once you logged on via TSO.
TSO log on screen
ISPF is a menu driver interface of TSO that user uses to interact with mainframe. ISPF provides various editors, utilities, and applications that provides complete access to mainframe. After logged on via TSO, to access ISPF, user enters command ISPPDF at the remedy prompt.
ISPF primary screen
To interact with UNIX on mainframe, you need UNIX shell. You can access this command interface either via OMVS command under TSO or through rlogin.
This is brief introduction on ways to interact with mainframe. There are few web based interfaces that you could use to talk to mainframe. Now that you know how to say ‘hello’ to mainframe, I would like to say ‘bye’ by ending this post :). Thanks for reading!
reference: MVS knowledge center