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Information Technology Infrastructure. Hardware . Hardware : The first building block. “Hardware: The parts of a computer you can kick” -- Source unknown “Computers in the future may weigh no more than 1.5 tons” --Popular Mechanics, forecasting the relentless march of science, 1949
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Hardware: The first building block “Hardware: The parts of a computer you can kick” -- Source unknown “Computers in the future may weigh no more than 1.5 tons” --Popular Mechanics, forecasting the relentless march of science, 1949 “But what ... is it good for?” -- Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip. “There is no reason anyone would want a computer in their home” -- Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977
The First?: ENIAC • February 15, 1946: Major General Gideon Barnes pushes a button in Philadelphia and changes the world. • Electronic Numerical Integrator and Computer represents the dawn of the Information Age
ENIAC • Size: 30’ by 50’ • Weight: 30 tons • 17,468 vacuum tubes • Needed six technicians in each shift • 1000 instructions per second • First bug was a live one that got grilled • Cost: $486,800 ($10 million present value)
ENIAC • “A new epoch in the history of human thought began last night...” • Philadelphia Enquirer, Feb. 16, 1946 • Story ran deep in the paper next to “Judge Frees 5 in Liquor Graft”
"I have always taken the position that there is enough credit for everyone in the invention and development of the electronic computer" - John Vincent Atanasoff The Atanasoff Controversy
Legacy of ENIAC: UNIVAC • First commercially available computer
Univac used in elections • Manufactured by Remington Rand • Used to predict 1952 US Presidential elections • Adlai Stevenson expected to win • UNIVAC posted 100:1 odds that opponent would win • Cronkite did not report the results because CBS didn’t believe them • Eisenhower won in a landslide
Computer Generations • Four major generations • Each distinguished by different base technology • Each generation significantly improved computational power while lowering costs • Cost of 100,000 calculations • 1950s: several dollars • 1980s: $.025 • 1995: $.00004
Computer Generations • First Generation (1946-1956) • Based on vacuum tube technologies • Huge tubes that burnt out quickly • Main memory 2000 bytes • Rotating drums used for hard disk and punch cards used for external storage • Typically used for limited scientific and engineering work
Computer Generations • Second Generation (1957-1963) • Based on transistor technology • Smaller than tubes, generated less heat • Main memory reached 32 KB • Speeds of up to 300,000 instructions per second • Used for science, engineering and some business tasks (payroll and billing)
Computer Generations • Third Generation (1964-1979) • Based on integrated circuits technology • Made by printing hundreds (later, thousands) of transistors on a silicon chip • Known as semiconductors • RAM expanded to 2MB • Speeds of upto 5 MIPs • Introduced software that could be used without extensive technical training
Computer Generations • Fourth Generation (1980-present) • Based on VLSI (very large-scale integrated circuits) technology • Packs tens of millions of transistors on a single circuit • Memory, logic, and control on a single chip – hence the term, microprocessor • Allowed the development of smaller machines
Power, Cost and Moore’s Law • 1965: Gordon Moore of Fairchild Semiconductors predicted that the number of transistors would double every24 months… • This has held for nearly 30 years • Intel plans to unveil a one-billion transistor chip capable of 100,000 MIPs in 2011 • Check site below for more information • http://www.intel.com/labs/eml/index.htm
What is a Computer System? Central Processing Unit(ALU + CU) Input Devices Secondary Storage buses Communication Devices Output Devices Primary Storage
The CPU • The Central Processing Unit (CPU) • Manipulation of numbers, letters, symbols • Controls other parts of the computer system • Consists of • Arithmetic Logic Unit (ALU) • Logical and arithmetic operations • Control Unit (CU) • Coordinates and controls other parts of system • Reads programs and directs other parts to performs tasks requested by program (machine cycle)
CPU- How Does it Work? • Control Unit – initiates fetch and execute cycles • Code cache – very fast memory on CPU chip • RAM copies instructions here for fast retrieval • Data cache fast access to small amounts of data • Instruction location counter – points to next instruction • Instruction decoder – analyzes what each instruction means • Integer and floating point unit – does math • ALU – does logical comparisons
Primary Storage • Sometimes referred to as primary memory or main memory • Three functions • stores all or part of the program being used by the CPU • stores the operatingsystem programs that manage the computer • store thedataneeded for the program being run • Random Access • Volatile
What is cache? • Moving data between RAM and CPU can take several clock cycles • To do it in a single cycle needs high speed memory (expensive) • Caches are small holding areas on the chip using high speed memory. • Chip designer add cache (called L1 cache) on the chip • Manufacturers sometimes add L2 cache which may or may not be on the chip.
Linking the CPU, Primary Storage, and other devices • Three kinds of buses • Data bus (moves data to and from RAM) • Address bus (signals for locating a specific address in RAM) • Control bus (signals to specify read/write operations for RAM and peripheral devices)
Processing Speed • Determined in part by • Word length (number of bits than can processed at one time by the machine) • Cycle speed (measured in MHz – internal beat set by control unit) • Data bus width (number of bits that can be moved at the same time) • Computation on more bits at a time • Cache memory • Floating Point calculations can be performed on hardware • Number of transistors • Pentium 4 has about 55 million on a single chip • Parallel processing
Categories of Computers • Mainframes • Largest of the computer types • Massive memory • Rapid processing power • Business, science, engineering applications • Demise greatly exaggerated
Categories of Computers • Minicomputers • Mid-range • Originally DEC aimed at getting a slice of IBM’s mainframe market (1957) • By 1969, scaled down version referred to as minicomputers
Categories of Computers • Personal Computers • Sometimes called a microcomputer • Local storage and processing • Workstations • Powerful math and graphics capabilities • Typical of engineering and design projects
Categories of Computers • Supercomputers • Can perform billions of calculations per second (GFLOP) • Based on parallel processing • Originally designed for military for weapon systems
Massively Parallel Computing(Fifth Generation) • Thousands of processors • Work in concert • Split the workload and process in parallel
Cluster Computing • Link computers together for faster performance or more reliable use • Two types • High availability clustering • Server A fails, Server B takes over without pause • Performance clustering • Servers A and B work together on single problem • Finish more quickly than either one could do alone
Categories of Computers • Network Computers • Also called “thin clients” • Minimal storage and processing • Download data and software from central server or Internet • Eliminates need for secondary storage devices • Aimed at reducing Total Cost of Ownership
The Future of Hardware Limited by physics and economics • Physics • Transistors currently etched using ultraviolet optical lithography • Can go down to 90 nanometers (200 atoms) • Below 100 nanometers – wavelengths of light too big – IBM using X-rays; Intel using Xenon; Lucent using beams of electrons • Intel has begun shipping the 90 nm technology in 4th quarter of 2003 • Economics • As size decreases, cost of fabrication increases • Currently, plants cost about $2.5b • For <100 nanometers, typically shoots to $10b • Need for “affordable scaling”
Software: The second building block “My software never has bugs; it just develops random features” --Source unknown