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Understanding Telecommunications and Networks in Management Information Systems

Explore the fundamentals of network communication systems, transmission media, data processing strategies, and network types. Learn about LANs, WANs, MANs, Ethernet, ATM, Bluetooth, Internet protocols, and advanced internet technologies. Discover the underpinnings of the Internet, network addressing, domain names, network access, internet protocols, email, and popular internet activities. Dive into the World Wide Web, internet communication, internet sites, e-commerce, government portals, and global internet trends.

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Understanding Telecommunications and Networks in Management Information Systems

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  1. 311: Management Information Systems Chapter 4: TelecommunicationsAnd Networks

  2. Telecommunication Systems

  3. GHI DEF “Connect to GHI” ABC MNO JKL Network • A Network is an Any-to-Any Communication System • Can connect any station to any other • Each Station has a Unique Network Address • To connect, only need to know the receiver’s address • Like telephone number

  4. Transmission Media • Twisted-Pair Wire • Telephone wire, Cat 5 • Coaxial Cable • Cable TV cable • Fiber-Optic Cable • 20 x price of twisted pair, 1000 x capacity • Microwave Signals • ’No, you don’t get toasted!’ • Satellites, line-of-sight • Infrared and Radio Signals • Wireless, short distance

  5. Media Types

  6. Data Processing Strategies • Centralized Processing • all processing occurs in a single location or facility • Decentralized Processing • processing devices are placed at various remote locations • Distributed Processing • computers are placed at remote locations and connected via telecommunication devices

  7. Terminal-to-Host Connection

  8. File Server Connection

  9. Client/Server Connection

  10. Client/Server Processing • Cooperation Through Message Exchange • Client program sends Request message, such as a database retrieval request • Server program sends a Response message to deliver the requested information or an explanation for failure Server Program Client Program Request Response Client Machine Server

  11. Networks • Local Area Network (LAN) • Connect computers in a single building or campus • Distances typically less than 1,000 meters • Wide Area Networks (WAN) • Connects computers across long distances • Typically several hundred kilometers • Example: Internet • Metropolitan Area Networks (MAN) • Connects computers in the same city • Up to 100 kilometers (often much less) Not in Book

  12. Network Types • Ethernet • Very popular, Cheap 10/100/1000 Mbps • Usually short distances • Asynchronous Transfer Mode (ATM) • Good for multimedia. Used for Internet access. • Up to 622 Mbps over long distances • Bluetooth • For connecting devices (printer, mouse etc) to PC. Short range, piconet, Max 1 Mbps • More wireless on next slide...

  13. Wireless alphabet soup • 802.11i – security standard

  14. The Internet Traffic travels across routers between LANs

  15. Technological Underpinnings • Internet Management • No owner! Managed by negotiation and non-binding contracts. May not continue to work. • Internet Engineering Task Force (www.ietf.org) decides on technical standards • World Wide Web Consortium (www.w3c.org) sets HTML and HTTP standards • Backbone network (gigabit connection) • http://www.caida.org/tools/visualization/mapnet/Backbones/ • Network Addressing • IP numbers: e.g. 140.252.13.33 (32 bits = 4 billion addresses) • The internet is running out of addresses! • Long-term solution: IP v6 (128 bits = 3.4 * 1038 addresses)

  16. More Technology… • Domain Names • Text version of IP address (translated by DNS) • Country domains (.dk, .uk, .de, .us) and generic domains (.com, .net, .org). USA also has .mil, .gov, and .edu. • NEW: .aero, .biz, .coop, .info, .museum, .pro, .name • Managed by ICANN (www.icann.org) • Network Access • No-one controls access! • Most people connect through an ISP • AOL and MSN largest ISPs (even though they are Online Services (OLSs)

  17. Internet Protocols • Internet Protocol (IP): standard that enables traffic to be routed from one network to another as needed • Transport Control Protocol (TCP): rules that computers on a network use to establish and break connections • Uniform Resource Locater (URL): an assigned address on the Internet for each computer

  18. E-mail (first time in 1971!) One of the most popular activities on the Internet! Becoming official business communication mode ListServ (http://www.lsoft.com/lists/listref.html) Newsgroups (Usenet) Go to http://www.google.com/grphp?hl=en Being outpaced by web-based fora Telnet FTP Streaming Internet Radio, Internet TV Real-Time Streaming Videoconferencing Chatting/IM Online collaboration Internet Telephony (VoIP) Web log (blog) Rich Site Summary (RSS) a.k.a. RDF Site Summary Internet Communication

  19. World Wide Web (www) Developed in 1989 • Hyper Text Transfer Protocol (HTTP) • Hyper Text Markup Language (HTML) • And derivatives/alternatives • SGML, DHTML, XML • URL • Browser • Search engines • Google most popular • Categories: Web crawlers (e.g. Google), categorized (e.g. Yahoo), Meta-search (search many engines) • Info on search engines: www.searchenginewatch.com • Review Question: What’s the difference between the Internet and the Web? http://www.uwosh.edu

  20. Types of Internet sites • Portals • A unified access site for many different sites (e.g. Excite, Yahoo, ...) • Can be topical (webMD), geographical (www.denmark.dk) • E-commerce • Government • Special Interest Groups • Informational • ...

  21. Internet Worldwide Trends • Rapid worldwide growth continues • Main use in • North America, Europe, Australia • Some use in • Asia, Middle East, Eastern Europe, South America • Virtually no use • Africa (90% in South Africa) • 80% of all international connections from Asia, Africa, S. America go directly to a US city

  22. Worldwide Trends • Online Population in million vs. World Population • Online: Jan. 2000 and Feb. 2002, Offline: Mid-2000

  23. Intranets and Extranets • Intranet • An internal corporate network built using Internet and World Wide Web standards and products; used by the employees of the organization to access corporate information. • Extranet • A network that links selected resources of the intranet of a company with its customers, suppliers, or other business partners; based on Web technologies. • Accessed by on-site employees • Passwords needed • Most company info can be put on intranet • Accessed by off-site employees and business partners • Passwords needed • Example: Online banking, TitanWeb

  24. Intranet and Extranet • Both use internet standards • Web pages, HTTP-protocol • Intranet • Within a company • Extranet • Outside access to a company’s intranet or specific web pages • Security: Virtual Private Networks (VPN)

  25. Electronic Data Interchange (EDI) • A system to electronically transfer business documents • Orders, bills, confirmations etc • ’Structured e-mail messages’ • Agreements/partnerships are set up in advance

  26. Issues in EDI • Data Standards • ANSI X.12: Used in the US • EDIFACT: Defined by UN. Used in much of the rest of the world • XML/EDI may help in the future • http://www.geocities.com/WallStreet/Floor/5815/ • Companies must use the same standard to communicate • Standards can be tailored to fit industries or individual businesses • Mostly for large companies • May force smaller business partners to use EDI

  27. Issues in EDI • Two Network Standards • Value Added Network (VAN) • Pro: High security, high capacity • Con: Price, incompatible hardware, only large companies • Internet • Pro: Cheap, ubiqutous, easy to use • Con: Security, capacity

  28. Virtual Private Network

  29. Ensuring Security of Information and Access • Firewalls • Security Management • Organizational procedures • Encryption and digital signatures • Secure Protocols • E.g. HTTPS

  30. Encryption Encryption: a process of making messages indecipherable except by those who have an authorized decryption key

  31. Single-key encryption • The sender of the electronic message (or payment) encrypts the information with a key • The receiver uses an identical key to decrypt the information to a readable form • The same code has to be in the possession of both the sender and the receiver • Problems: if a key is transmitted or intercepted illegally, it could be used to read all encrypted messages

  32. Public/private key encryption • Two different keys - public key and private key • Several authorized people may know the public key, but only its owner knows the private key • Every person has one private key and one public key • Encryption and decryption can be done with either key • If encryption is done with the public key, the decryption can be done only with the private key and vice versa • Problem: Slower than single-key encryption • Try it out: go to http://www.pgp.com/products/freeware.html • Freeware version: No commercial use! • 8.6 MB download

  33. Public/Private Key Encryption

  34. Coming Up • Thursday • Lab 4 due • Tuesday • Lecture on Chapter 5 • Note: GUI has been moved

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