Mainframes are Servers, the way we have client-server computing today, but they are not called servers because the "clients" of a mainframe system are usually terminals. These are dumb terminals, which means all the applications they run on big system. Nothing is being served to the client...all the work is done on the big machine. A Mainframe is usually dedicated for one purpose like a Hospital or IRS.
Now, look at the definition of "client-server computing", and you will understand it is not the same as a Mainframe system.
Client/server describes the relationship between two computer programs in which one program, the client, makes a service request, the server fulfills the request. Although client/server idea can be used by programs within a single computer, it is a more important idea in a network.
Relative to the Internet, your web browser is a client program that requests services from a web server(HTTP server) in another computer somewhere on the Internet.
To make it simpler let's take the example of Television broadcast station and Television sets as our client/server model.
A server is sort of like a television broadcast station, making its information available to anyone who would like to receive it. Clients are like television sets - you tune it in to the station you want to watch. The television broadcast station sends the signal in a standard format which is ready for viewing by any of television set, which may be black and white, color, big screen, what ever.
You can take the example of your bank account also.
To check your bank account from your computer, a client program in your computer forwards your request to a server program at the bank. That program may in turn forward the request to its own client program that sends a request to a database server at another bank computer to retrieve your account balance. The balance is returned back to the bank data client, which in turn serves it back to the client in your personal computer, which displays the information for you.
Generally Mainframe machines are servers. You throw tasks to the Mainframe machine, and the mainframe performs the processing, and stores the result. Many users throw requests to the Mainframe machine concurrently. Thus, as a mainframe operator, generally you would not be present physically near the machine, you operate it remotely. you have a keyboard and monitor connected to your Mainframe server. There would be thousands of terminals connected to a mainframe server and many users can perform their tasks on the mainframe server concurrently. You might sit in the work-office of your company on a terminal and perform data-processing on the Mainframes server located somewhere else.
Now, look at the definition of "client-server computing", and you will understand it is not the same as a Mainframe system.
Client/server describes the relationship between two computer programs in which one program, the client, makes a service request, the server fulfills the request. Although client/server idea can be used by programs within a single computer, it is a more important idea in a network.
Relative to the Internet, your web browser is a client program that requests services from a web server(HTTP server) in another computer somewhere on the Internet.
To make it simpler let's take the example of Television broadcast station and Television sets as our client/server model.
A server is sort of like a television broadcast station, making its information available to anyone who would like to receive it. Clients are like television sets - you tune it in to the station you want to watch. The television broadcast station sends the signal in a standard format which is ready for viewing by any of television set, which may be black and white, color, big screen, what ever.
You can take the example of your bank account also.
To check your bank account from your computer, a client program in your computer forwards your request to a server program at the bank. That program may in turn forward the request to its own client program that sends a request to a database server at another bank computer to retrieve your account balance. The balance is returned back to the bank data client, which in turn serves it back to the client in your personal computer, which displays the information for you.
Generally Mainframe machines are servers. You throw tasks to the Mainframe machine, and the mainframe performs the processing, and stores the result. Many users throw requests to the Mainframe machine concurrently. Thus, as a mainframe operator, generally you would not be present physically near the machine, you operate it remotely. you have a keyboard and monitor connected to your Mainframe server. There would be thousands of terminals connected to a mainframe server and many users can perform their tasks on the mainframe server concurrently. You might sit in the work-office of your company on a terminal and perform data-processing on the Mainframes server located somewhere else.
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