Welcome to CMPE003 Personal Computers: Hardware and Software

1. Welcome toCMPE003Personal Computers: Hardware and Software Dr. Chane Fullmer Fall 2002 UC Santa Cruz

2. Assignments • Homework #4 – Due October 25 (That’s this coming Friday  ) • Design your own resume • Must use a Word Processor (ie, M$ Word) • Notepad will not suffice. • Details and sample resume – see class page – http://www.soe.ucsc.edu/classes/cmpe003/Fall02/hw4_resume.html

3. Class Information • Midterm results: • Didn’t change with rescan … • Will be handed back after lecture today – for real 

4. The Internet:A Resource for All of Us Chapter 8 Part A

5. Objectives • Describe some of the history of the Internet • Explain what is needed to get on the Internet • Describe generally what an Internet service provider does • Describe the rudimentary functions of a browser • Describe how to search the Internet • List and describe the non-Web parts of the Internet • Explain some of the ongoing problems associated with the Internet

6. History of the Internet • Government and Universities over 30 years • Who’s connected today? • Individuals • Educational institutions • Government/Military/Police • Research • Medical • Businesses • Everyone!

7. The Early Years • 1969 – US Department of Defense and Rand Corporation • Origins • Cold War – fear that a bomb could demolish computing capabilities • Several computers, geographically dispersed, networked together • Plan – if one computer was disabled, others could carry on using alternative communication routes

8. The Early Years • Many WANs and LANs were installed, but machines on the WANs could not access information on the LANs.. • Remote access was separated from local access • A single cohesive network was desirable.

9. The Early Years • US Department of Defense had a similar scenario – lots of autonomous networks that could not interoperate • The DoD funded network research in the early ’70s through (D)ARPA creating various network technologies, including a research WAN called ARPANET.

10. The Early Years • ARPANET allowed researchers the opportunity to build a working test-bed for networking ideas. • Solved incompatibility issues • Solved interoperability issues • Created an internetwork of LANs and the WANs • The Internet is born

11. The Early Years ARPANET Backbone G2 MIT LAN G1 UCB LAN DARPA LAN UCLA LAN G3 G4

12. The Early Years… • Internet Software • Internet Protocol (IP) • Provides basic communication • Handles the addressing and routing • Transmission Control Protocol (TCP) • Provides services for applications to communicate • Packetizes message, reassembles message at the destination • The “TCP/IP Internet Protocol Suite” • aka TCP/IP

13. The Early Years • ARAPA placed the research and software into the public domain. • All information was freely available to any person or vendor, allowing them to create devices or networks that would interoperate with the Internet technology. • Improvements were documented and made publicly available. • This philosophy is called an Open System

14. The Early Years • Internet documentation • On-line and accessible from the Internet • Reports for improvements to the Internet were initially a two step process • Request for comments (RFC) went out first • Internet Engineering Note came out with the comments as the final report. • Today the RFC remains as the definitive documentation for the Internet • On-line at www.faqs.org/rfcs/ • Also www.ietf.org/rfc.html

15. The Early Years • The UNIX operating system • Built at Bell Labs in the early ’70s • UNIX given to universities to study • UC Berkeley team added LAN software • Distributed to others via the Berkeley Software Distribution (BSD) and became known as BSD UNIX (The ancestor of today’s Free BSD)

16. The Early Years • ARPA negotiated with UCB to add the TCP/IP suite to the BSD UNIX release. • Gave large number of universities access to study networking, and deploy it in their departments. • 1982 the US Military chose the Internet as its primary communication system. • 1983 the ARPANET began running TCP/IP exclusively.

17. The Early Years • Incredible growth from day one.. • In 1982 ~200 machines were connected • By 1983 the number had doubled • With growth comes the problems.. • Static lists of machines need updated • Limited memory space … • Software updates..

18. The Early Years • The Computer Science Network (CSNET) • Sponsored by NSF in early `80s • Goal was to connect every Computer Scientist in the country over one network. • CSNET was deployed using TCP/IP and the Internet • By mid 1980s most major university and research labs were connected to the Internet • Graduate students began to investigate the details of these new technologies, and include them in their research topics. • Developed new applications • Extended the technology

19. The Early Years • The IAB (Internet Activities Board) (Now known as the Internet Architecture Board) • Original controlling body to coordinate TCP/IP research and Internet development. • Chairman – Internet Architect • RFC Editor • Formed volunteer task forces to solve problems • Task forces generated new RFCs

20. The Early Years • The IETF (Internet Engineering Task Force) • Originally chartered for short-term Internet development. • Now is responsible for most of the Internet technical development • Working groups meet and create the RFCs • Manet, ipsec, tcp…

21. The Early Years • NSFNET • NSF recognized the importance of the Internet to the scientific community. • Interconnected the supercomputer centers around the US with a TCP/IP WAN • Proved useful, but small • NSF looked for ways to improve the ARPA Internet

22. The Early Years • The NSFNET Backbone • 1988 WAN established as main backbone of the Internet • MCI – long distance transmission lines • IBM – dedicated computers and software • MERIT – network operation

23. The Early Years • The ANS Backbone (Advanced Networks and Services) • Consortium of MCI, IBM & MERIT • Allowed the government to begin privatization of the Internet • 1992 – WAN was built to serve as the Internet backbone • ANSNET, 30 times NSFNET capacity

24. The Early Years • Exponential growth …….

25. The Early Years • By 1999, the Internet was growing so fast that, on average, a computer was added to the Internet every second – and the rate continues to increase. • An interesting fact: • At any time from 1983 through 1999, approximately half the growth of the Internet occurred in the previous 12 months… • So, after you have been “on” the Internet for only one year, you will have had more experience than half the other users….

26. The Early Years • Growth – Good and Bad • Good for vendors • Bad for the IETF • Predictions of imminent collapse • March 1993, Summer ’97 • Technology improvements have kept up with bandwidth and switching speeds required.

27. The Early Years • The Hard limit – Address space • The IP protocol is limited to a number contained in 4 bytes (32 bits)… Byte 3 Byte 2 Byte 1 Byte 0 • This limits the number of possibilities to 232 = 4,294,967,296 • There are solutions – IPv6, NAT

28. The Early Years • Summary • The Internet began as an ARPA research project. • The TCP/IP protocol software was developed to make the Internet operational. • The Internet is an Open System, with the technology freely available to all. • The Internet documentation is available on-line in the form of reports known as RFCs.

29. The Early Years • Summary (continued) • BSD UNIX distributed TCP/IP suite freely to universities in the early 80s • 1982 US Military adopted TCP/IP as primary communication standard • Exponential growth from its inception • IAB formed to coordinate development • IETF - major technical development body • Working groups

30. The Early Years • Summary (Continued) • 1988 – NSFNET Backbone • 1992 – Privatization (ANSNET) • Exponential growth from its inception • Half of the users today have been there less than one year…… • IP Address 32 bit limitation

31. Tim Berners-Lee • 1990 • Perceived a spider’s web of computers with links from computer to computer • CERN site • Dr. Berners-Lee’s physics laboratory • Birthplace of the World Wide Web • Easy movement due to links • Hypertext • Hyper-region

32. Marc Andreessen • 1993 • Created browser software • Mosaic – first graphical browser • Became Netscape (now owned by AOL) • Provided attractive images and a graphical interface permitting users to click on pictures as well as text

33. Internet Explosion • September 2002 • Over 600 million users worldwide • Part of our daily lives • Four factors • TCP/IP standard • Ability to link from site to site • Ease of use of browser • Growth of PC and LANs that can connect

34. Global Internet Usage

35. URLUniform Resource Locator • Unique address of a web page or file on the Internet • Case-sensitive http://domain-name.top-level-domain/last-section

36. httphypertext transfer protocol • Protocol – rules • Communication using links http://domain-name.top-level-domain/last-section

37. Domain name • Address of the ISP • Domain names are registered • Ongoing fee is paid for each domain name http://domain-name.top-level-domain/last-section

38. Top-level Domain Represent the purpose of the organization of entity .com .gov .edu .org .net May be a two-letter country code

39. Last section Directories and file names that specify a particular web page http://domain-name.top-level-domain/last-section

40. Getting Started • Computer with a modem or NIC • Internet service provider (ISP) • Browser client • Other related software

41. The Midterms