9.4 Case Study: Asynchronous Transfer Mode Historically, there have been different networks that carry different types of information: • Telex (old style teletypewriters, used for news feeds, stock quotes, etc.) • “Plain old telephone service” (POTS) via the public switched telephone network (PSTN); • Data, via the packet switched data network (PSDN); • Television via: […]
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Principles of computer architecture
Communication: network architecture: the internet (the internet mode land bridges and routers revisited, and switches).
9.4 Network Architecture: The Internet In the early days of computing, computers were centralized facilities that contained most or all of the resources used by the populations they serviced. Data was transferred between computers via media (punched paper cards, paper tapes, magnetic tapes, and magnetic disks), hand-carried by an operator. As the number of computers […]
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Communication: communication errors and error correcting codes (bit error rate defined, error detection and correction, vertical redundancy checking and cyclic redundancy checking).
9.4 Communication Errors and Error Correcting Codes In situations involving communications between computers, and even inside of a computer system, there is a finite chance that the data is received in error, due to noise in the communication channel. The data representations we have considered up to this point make use of the binary symbols […]
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Communication : transmission media (two-wire open lines, twisted-pair lines, coaxial cable, optical fiber, satellites, terrestrial microwave and radio).
9.1 Transmission Media In a geographically close environment, computers can be networked with private cables in a number of configurations. For geographically distant systems, the public switched telephone network (PSTN) can be used. Users connect to the PSTN with modems that convert logical bits into audible sounds. People can hear at frequencies up to about […]
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COMMUNICATION : Modems
COMMUNICATION “Communication” is the process of transferring information from a source to a destination. Communication systems for the most part cover distances between computers, and may involve the public telephone system, radio, and television. Wide-area communication systems have become very complex, with all combinations of voice, data, and video being transferred by wire, optical fiber, […]
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SUMMARY OF INPUT AND OUTPUT
■ SUMMARY Input, output, and communication involve the transfer of information between transmitters and receivers. The transmitters, receivers, and methods of communication are often mismatched in terms of speed and in how information is represented, and so an important consideration is how to match input and output devices with a system using a particular method […]
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Input and output: output devices (laser printers and video displays).
Output Devices There are many types of output devices. In the sections below, we explore two common output devices: the laser printer and the video display. LASER PRINTERS A laser printer consists of a charged drum in which a laser discharges selected areas according to a bit mapped representation of a page to be printed. […]
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Input and out put: input devices (keyboards, bit pads and mice and trackballs).
8.6 Input Devices Disk units, tape units, and drum units are all input and output (I/O) devices, and they share a common use for mass storage. In this section, we look at a few devices that are used exclusively for input of data. We start with one of the most prevalent devices – the keyboard. […]
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Input and output: mass storage (magnetic disks, magnetic tape, magnetic drums and optical disks).
8.5 Mass Storage In Chapter 7, we saw that computer memory is organized as a hierarchy, in which the fastest method of storing information (registers) is expensive and not very dense, and the slowest methods of storing information (tapes, disks, etc.) are inexpensive and are very dense. Registers and random access memories require continuous power […]
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Input and output: case study: communication on the intel pentium architecture ( system clock, bus clock, and bus speeds, address, data, memory, and i/o capabilities, data words have soft-alignment, bus cycles in the pentium family, memory read and write bus cycles, the burst read bus cycle, bus hold for request by bus master and data transfer rates).
8.2 Case Study: Communication on the Intel Pentium Architecture The Intel Pentium processor family is Intel’s current state-of-the art implementation of their venerable x86 family, which began with the Intel 8086, released in 1978. The Pentium is itself a processor family, with versions that emphasize high speed, multiprocessor environments, graphics, low power, etc. In this […]
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