1. Introduction to Telecommunications
Chapter 1
Introduction to Telecommunications

2. Communication
1. Process that allows information to pass between a sender and receiver
- or -
2. Transfer of meaningful information between two locations
Meaningful implies perception

3. Telecommunications Tele means far off or distant
Telecommunications today means communication by electrical or electromagnetic means, usually over a distance

4. Data Communications
Subset of telecommunications excluding analog signals
Non much analog these days

5. Data vs. Information
Data - representation of facts, concepts, etc. suitable for communication
Information - meaning associated with data

6. Telecommunications Elements
May have multiple transmitters in a system
Form networks
Rules or protocols
Example: establishing communications requires
Initiation
Identification of sender and receiver
Order of communication

7. Basic Telecom System Elements

8. Telecom and Business
Business must move data and voice information within locations and between locations
Timing
Information must be available when needed
Telecom advances are revolutionizing information transfer
Competitive business must maximize use of information for marketing and productivity enhancement
Transactions
Airline reservations, banking, marketing
Used for availability, location, shipping accounting
Online business: E-commerce

9. Telecom and Business Reduces effect of geography
Link remote branches with voice/data/video
Mobile communications
Telecommuting

10. Telecom Examples

11. Telecom Examples

12. Telecom Examples

13. Telecom Examples

14. Telecom Examples

15. Telecom Examples

16. Telecom System Requirements (Data System)
Availability
System ready and operating when needed
Reliability
System trouble free and error free
Real time or real-enough time
Response time
System does not hinder user by introducing too much delay
Ease of use
Ergonomics
Flexibility and scalability
System easy to change to meet future needs

17. Availability Variable requirements Time zone effects
Some applications need round-the-clock availability
Some businesses operate 8am to 5pm
Time zone effects
Must take into account working hours in other locations you must communicate with, nationally and internationally

18. Reliability MTBF - mean time between failure
MTTR - Mean time to repair
How long does it take to repair system?
Reduce effects of failure with redundant (backup) components

19. Reliability Example 1
Overall reliability in a cascaded system is always lower than the least reliable component

20. Reliability Example 2

21. Telecommunications Timeline

22. Key Telecom Events 1847 - Telegraph 1877 - Telephone
American Telephone and Telegraph Company (AT&T) formed
Radio
Communications Act of 1934 (FCC)
Television
Microwave communications
First transatlantic telephone cable TAT-1
Satellite
1960s Computer/Terminal communications

23. Key Telecom Events 1969 - ARPANET An experimental data network
Fiber optics
1970s - Dial-up computer communications
Cellular phone
IBM PC
AT&T Divestiture
1980s - LAN
World Wide Web (WWW)
Telecommunications Act of 1996
1990s - Intranet, Extranet, E-Commerce, growth of wireless
Late 1990s - media convergence

24. Internet Timeline

25. Key Internet Events
Leonard Kleinrock publishes paper on packet switching
ARPANET test
Network Control Protocol (NCP) implemented on ARPANET
Kahn and Cerf publish paper on TCP/IP
hosts on ARPANET
USENET newsgroup network

26. Key Internet Events
Internet Activity Board (IAB) created to oversee protocol development
TCP/IP version 4 adopted for ARPANET
hosts
Domain Name System (DNS)
National Science Foundation Network (NSFNET)
Worm virus
Computer Emergency Response Team (CERT)
ARPANET retired

27. Key Internet Events 1991 - Gopher menu-driven Intenet interface
Tim Berners-Lee develops World Wide Web
,000,000 hosts
Mosaic graphical WWW interface
Internet Network Information Center (InterNIC)
,000,000 hosts
NSF stops supporting NSFNET
Internet goes commercial
Internet Service Providers (ISPs)

28. Key Internet Events
NSF starts supporting Very-High-Speed Backbone Network Service (vBNS)
Telecommunications Act of 1996
,000,000 hosts
1997 to present - E-commerce, distance learning, Voice-Over-IP, Virtual Private Networks, etc.

29. Major Internet Components
Backbone
Main infrastructure of Internet
Main nodes connected by T1, T3, OC3, OC12 links
Backbone routers
Packet switches route data
A DSU/CSU (Data Service Unit / Channel Service Unit) interfaces router to backbone
Internet Service Provider (ISP)
Company that links many users to backbone

30. Major Internet Components
Concentrator
Interfaces several network technologies in a single chassis
Similar to a router
Site Router
Also known as an Access Router or Premise Router
Connects a customer-s computers to the ISP

31. Major Internet Components
T. Fallon, The Internet Today, Upper Saddle River, NJ, Prentice Hall, 2000

32. Case Study - Dow Corning
Headquarters in Midland Michigan
Business
Develop, manufacture, and market silicones and related products
Business structure requires close coordination between marketing, manufacturing, etc.
Telecom at Dow Corning
Responsibility lies within corporate Information Technology (IT) department
Data and voice responsibilities brought under same group in 1982

33. Case Study - Dow Corning
Data and voice responsibilities brought under same group in 1982
emphasis on interaction between CIS department and telecom people in manufacturing areas
Network (in 1999)
11,000 personal computers and terminals
5,800 in U.S.
Goal to provide rapid response time for most transactions

34. Case Study - Dow Corning

35. Case Study - Dow Corning