2. Page 1 - © Richard L. Goldman Mainframe Networking ©Richard L. Goldman January 7, 2002

3. Page 2 - © Richard L. Goldman Mainframe Computer Large powerful computer Capable of supporting hundreds of terminals Often used to support a WAN IBM

4. Page 3 - © Richard L. Goldman Minicomputer Smaller version of a mainframe computer Capable of supporting many terminals Often use to a support a LAN IBM

5. Page 4 - © Richard L. Goldman Microcomputer A standalone computer capable of doing its own processing May be networked May function as a terminal Also known as a PC (Personal Computer) Also know as a Mac (Apple Macintosh)

6. Page 5 - © Richard L. Goldman Terminal Normally a VDT (Video Display Terminal) with a keyboard Performs basic input and output functions Must be connected to a host computer May possess additional intelligence May possess additional functionality

7. Page 6 - © Richard L. Goldman Basic Terminal Types Dumb Smart Intelligent Programmable POS (Point of Sale) Credit Card Authorization Fax (Facsimile) Printer Phone Remote Input ATM (Automated Teller Machine)

8. Page 7 - © Richard L. Goldman Dumb Terminal Does not have memory Each character is sent to host when it is typed (uncontrolled mode) Host must continuously monitor for input Operates asynchronously

9. Page 8 - © Richard L. Goldman Smart Terminal Has memory Screen formats are received from the host After entered - data is sent to host one block (one screen) at a time Data is sent only when polled (controlled mode) Operates synchronously

10. Page 9 - © Richard L. Goldman Intelligent Terminal Has memory and programs (in firmware) Operates similar to smart terminal except it may be operated offline. Only needs to go online to acquire screen formats or to transmit data.

11. Page 10 - © Richard L. Goldman Programmable Terminal A specialized standalone microcomputer May be reprogrammed as needed Only needs to go online to communicate with the host

12. Page 11 - © Richard L. Goldman Mainframe Network Devices Concentrator FEP (Front End Processor) Controller Protocol Converter Gateway

13. Page 12 - © Richard L. Goldman Concentrator A computing device used to combine the input from many different terminal for input to the mainframe. Has data validation and store and forward capability Routes data from host to proper terminal IBM Concentrator

14. Page 13 - © Richard L. Goldman FEP (Front End Processor) A powerful computing device used to perform all the functions of a concentrator plus most of the communication processing. Polling, error checking and correction, flow control, data conversion, message switching, etc. IBM FEP

15. Page 14 - © Richard L. Goldman FEP With local controller A controller is: –A scaled down version of a FEP –A device that connects multiple devices to the FEP –Used locally or remotely IBM FEP Controller

16. Page 15 - © Richard L. Goldman FEP With remote controller and modems IBM FEP Controller Modem

17. Page 16 - © Richard L. Goldman FEP With Multiplexers A multiplexer is a device that: –Combines several signals for transmission over a single media –Must always be used in pairs IBM FEP Multiplexers

18. Page 17 - © Richard L. Goldman FEP Protocol Converter A protocol converter converts a client’s protocol to match the mainframe protocol. The converter may be either a hardware device or software. A hardware converter may be located locally or remotely. A software converter may be run on either the mainframe or the client computer. IBM Terminal PC Terminal Protocol Converter

19. Page 18 - © Richard L. Goldman FEP Ethernet LAN Gateway A gateway is a type of protocol converter that provides conversion for an entire network. IBM Terminal PC Hub Terminal Gateway Protocol Converter