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Technology Themes Over Time. CPIS 210 ch01. Moore’s Law. Original: The amount of memory available on a chip (which tends to be constant cost) doubles about every 18 months Now: We tend to assume this applies to every performance-related number in IT
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Technology Themes Over Time CPIS 210 ch01
Moore’s Law • Original: The amount of memory available on a chip (which tends to be constant cost) doubles about every 18 months • Now: We tend to assume this applies to every performance-related number in IT • Reality: Some numbers are very hard to increase • So we find another way to do that function that is inherently faster
Serial vs Parallel • Early belief: Parallel is inherently faster than serial • Current practice: Go serial, but go fast • Progression: • Parallel to maximize low-speed lines • Faster serial line • Fiber • See this in networking, disc drives, video
How Purposes Change • Highest-priority purposes dominate when costs are high • 1940s: Ballistics table for new weapon • New uses appear when costs moderate • 1960s: Payroll • Radical re-purposing as costs become trivial • Blinking lights sold at Dollar Tree
Standardization • Old approach: Everything is part of “our” product line • Medium approach: “Our” product is core, but to do x you’ll need this additional device from another vendor: • Emerging approach: Multi-vendor environment ruled by standards • What about your entity directory? • Issue: Do you have multiple vendors within a given box? • Issue: “We go beyond the standard to get better [performance][features].”
Energy • Mainframe supplied by carefully-conditioned power w/backup • Distributed system – using local UPSs as needed • Extremely low-power devices: batteries, solar • What happens to your data when power fails? • How does the system function when power is out • How do you return to normal operation after power is restored?
Configuration Methods • Manual / hardware • Jumpers and switches • Manual / software • Early: Connect VT100 terminal • Current: Device contains a mini Web server • Automatic (self-discovery) • Easier to set up in most cases • If using a program, must run on workstation • Problems resulting from design errors or glitches can to be very difficult to solve • Nice to have a manual config option
Configuration Memory • CMOS • FLASH • Hard drive • Backup/Restore? • A major issue for CSAs: Where is the data physically kept?
Why Use IT? Business Models • Computers give us more efficiency • Calculating FICA in payroll • Controlling inventory at big-box stores • Computers allow us to be more flexible • Handling new compensation formulae for sales people • Computers enable new business models • RedBox