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Explore the transformative era of workstations and UNIX systems from 1981 to 1995. This chapter delves into the development of affordable microprocessor-based workstations led by pioneers such as Bill Joy and Vinod Khosla. Learn about the milestones such as the introduction of Apollo's first workstation, the significance of Berkeley UNIX, and the impact of RISC architecture. The collaboration of universities and tech companies laid the groundwork for extensive networking capabilities, shifting from traditional mainframes to more agile systems. Discover the legacy of these advancements that paved the way for modern computing.
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Chapter 9 - 1981 to 1995 Workstations, UNIX & the Net
Next Step - Workstations • Inexpensive microprocessor • Motorola 68000 • Cost less than mini; more than PC • Main Features • UNIX • Extensive Networking Capabilities • Idea: Attach these to mainframe rather than dumb terminal
Apollo - First Workstation • Bill Poduska, from Prime Computer • Domain: own OS and NW system • $40,000 • Used for CAD & engineering • Mid-1980 - sold 1,000 • 1989- bought by H.P.
Sun Microsystems • 1982- founded by Vinod Khosla • Also Bill Joy • Stanford University Network Workstation • Andy Bechtolsheim • June 1982- SUN-2, $20,000 • Berkeley UNIX First Sun Workstation - 1983
UNIX • AT&T Bell Labs, NJ; Ken Thompson, Dennis Richie • Not a complete OS • Set of tools to manipulate & share files • Due to legal actions • AT&T couldn’t sell for profit • Universities got license for cheap • Commercial could also buy • Open Source
The UNIX Journey • Developed in New Jersey • To easily share files; Very frugal • Not for masses • Univ. of Illinois-Champagne-Urbana • U.C. Berkeley • Extensively rewritten • Bill Joy • Took it to SUN
UNIX and Universities • Cheap source code • Written in C; run any machine with C compiler • Free to modify code - and they did • Berkeley Software Distribution (BSD) UNIX • 1978-Joy offering tapes cheap
Universities (cont.) • 1980 - ARPA backed BSD • Version 4.2 • Network Protocol TCP/IP • ARPA promoted TCP/IP
UNIX * Miscellaneous • VAX - Berkley UNIX w/ TCP/IP • Helped transform ARPANET to Internet • Vulnerable to viruses • Never really challenged Windows • Not even LINUX, yet
Vax Strategy - 1980’s • Offer single architecture (VAX) with single OS (VMS) in solitary or networked configurations ranging from desktop to mainframe capability • Networking – Ethernet - from Intel & Xerox • “The network is the computer.” • Several Modes: 11/780, 11/750, MicroVAX II, 8600 (Venus), 9000
Vax Strategy Risks • Similar to IBM’s “betting the company” • Had to supply customers with everything without seeming to change too much • Entire line had to be high in quality
Risks (cont.) • Stop marketing its own competing H.W. • PDP-10- Outdated • Public outcry over PDP-10 & DECtape • Phase out an announcement • Historical Perspective- Pg. 186
Vax Strategy Results • Did not stick with it • 1982 - 3 incompatible machines (not IBMPC compatible, either) • Strategy went well through 1980’s • 1987 stock market crash • Plus Competition from UNIX workstations and IMBPC • DEC couldn’t recover #2 position
RISC • Reduced Instruction Set Computer • IBM-360, DEC VAX • Complex Instruction Set Computer (CISC) • 200+ instructions, each • Due to slow access core memory • Due to immature compilers • Trying to close “English Instruction” gap • Cheap ROM allowed low cost of CISC
RISC- More #1 • John Cocke, IBM • Due to improved technology, believed smaller set of instructions with more loads and stores would be faster than 370 • Experimental: IBM 801, 1979 • Did not make market • 1980 - Berkeley- RISC Project • 1981- Stanford • MIPS (Millions of instructions per second) • Skepticism outside university environment • Everything else booming- so why change?
RISC - More #2 • 1987- SUN SPARC- RISC Chip • Scalable Processor Architecture • Overcame Skepticism • RISC improved microprocessors speeds faster than mainframe & mini- processors were improving • Sun Licensed SPARC to others • Hoped it would become the standard • But would not be profitable
RISC – More #2 (cont.) • MIPS computer systems • Stanford MIPS project • DEC bought RISC chip for workstation • Silicon Graphics • 1990- IBM R/6000 • 1990’s early: IBM & Apple • Power PC, Motorola Chip
Workstation vs. PC • RISC Architecture • Scientific & Engineering Apps. • Networking (Ethernet) • Cost
Ethernet • Developed @ Xerox PARC, 1973 • Robert Metcalfe & David Boggs • Metcalfe • At MIT in 1969- helped connect PDP-10 to ARPNET – to do same in ‘72 at PARC • Focus @ PARC was local networking • PARC Local Network • Data General minis in star technology • Expensive, inflexible, not robust
ALOHAnet • To connect among Hawaiian Islands • Radio Signals Wireless • Packets of 1000 bits; address of recipient attached to head of each message • Computers turned to UHF frequency & listened for packets
Network Features #1 • Radio (medium) was passive • Computers (Nodes) did the work • Process, queue, route • “Ether”- invisible medium • Replaced by coaxial cable • New Computer just taps into cable
Network Features #2 • Computer “listens” before sending • Collision: random pause, try again • If many collisions, send less frequently • Math analysis showed would work • 1974- Running @ 3 million bps • Arpanet 50 (telephone) - kilobits/sec
Ethernet Impacts • Speed changed relationship between small and large computers • 1st affected workstations, then PC market • DEC, INTEL, Xerox: accepted as standard for VAX • DOS/ Early PC chips - not well suited for networking
Apple PC’s • With Lotus 1-2-3, Word Processing, and dBase III, IBM compatibles began to replace Apples and Word Processors in office environment • Less expensive clones
“Personal” Computing in Business • Employees had personal SW • Not in line with business goals • Some sw not very good • Became problem for I.S. people • So LAN’s helped to “control” technology • Irony: networking made it not so personal
Novell • Networking practical after 80386 • 1989 - had half business • Complex, expensive, overlaid DOS • File server with software • Not as good a UNIX networking with workstations • Backups, messaging, sharing
Internet • LAN’s provided access to Internet • Key features • Descendent of ARPANET • Packet switching • No dedicated line necessary • TCP/ IP- standard protocol • Open to public, commercial
Internet Success • ARPA’s support; adoption of TCP/IP in 1980 • TCP/IP inclusion into Berkeley UNIX • Not proprietary • Rise in number of LAN’s
Success (cont.) • Ethernet Speeds • Grove’s Law • Telecommunication bandwidth doubles every 100 years • Cable, etc. have improved • “Last Mile Problem”
Internet Before WWW • Arpanet- goal was resource sharing • FTP, Telnet: had to know location of information • Email - did emerge • Groups • Bulletin Boards, Discussion Groups, Etc. • Gopher- 1990/91 • Univ. of Minnesota • Search for Data on campus • Spread
Before WWW (cont.) • WAIS - Wide Area Information System • Thinking Machines Corp., Cambridge • Searched documents & made index of words • All were short lived • But demonstrated what could be done
WWW - The Beginning • Doug Englebart: mouse + on-line system, NLS • Vannevar Bush: 1945 paper - hypertext • Ted Nelson: Xanadu System • Computer Lib/Dream Machines • Hypertext: forms of writing which branch or perform on request; they are best presented on computer display screens • Worked on Xanadu during 70’s & 80’s • Apple Macintosh HyperCard - 1987
WWW Finally • Tim Berners-Lee @ CERN • European particle physics lab • Swiss- French border • Features and Goals • A shared information space, inclusion • Across platforms • URL- Uniform Resource Locator • To avoid database restrictions • HTTP- to replace FTP • HTML
WWW Early Years • Slow Start - few but CERN supported • Hard to program links • Just a few browsers- • Lynx & Viola
Mosaic • Marc Andreessen & Eric Bina • U. of Illinois • January 1993- released Mosaic, a browser, over the Internet • Used Mouse, hypercard • Links in different color • Seamless integration of text and graphics • Re-written for Windows and Macintosh
Netscape Navigator • 1994 – Jim Clark, Silicon Graphics • Commercialize Mosaic • Univ. of Illinois – objected • Andreessen had been a student there • Clark & Andreessen • Netscape Communications Corp • Mosaic died • 1995 – Public release of stock • $28 $58 (day 1) $150
Chapter 91981-1995 Workstations, UNIX & the Net