Telecommunications and Networks

1
Telecommunications and Networks

• Understand the concept of a network.
• Apply Metcalfes law in understanding the value
  of a network.
• Identify several major developments and trends in
  the industries, technologies, and business
  applications of telecommunications and Internet
  technologies.
• Provide examples of the business value of
  Internet, intranet, and extranet applications.

2
Learning Objectives

• Identify the basic components, functions, and
  types of telecommunications networks used in
  business.
• Explain the functions of major components of
  telecommunications network hardware, software,
  media, and services.
• Explain the concept of client/server networking.
• Understand the two forms of peer-to-peer
  networking.
• Explain the difference between digital and analog
  signals.

3
Learning Objectives

• Identify the various transmission media and
  topologies used in telecommunications networks.
• Understand the fundamentals of wireless network
  technologies.
• Explain the concepts behind TCP/IP.
• Understand the seven layers of the OSI network
  model.

4
Case 1 Best Buy, MedStar Health, and Unifi The
Challenges and Benefits of Wireless Mobile
Applications

• Geek Squad is a 24-hour response unit that offers
  computer and network support for home PC users or
  businesses without an onsite IT staff.
• They use wireless Pocket PCs and other mobile
  devices to access companys business
  applications.
• The biggest challenge - typing on their small
  pocket PCs.
• Many businesses that provide or manage employees
  mobile devices for accessing company information
  are developing their own software for mobile
  devices.

5
Case Study Questions

• What are the business advantages and limitations
  of the Best Buy Geek Squads use of their
  wireless Pocket PC mobile devices? How have they
  overcome the limitations of their mobile devices?
• What are the software development challenges of
  wireless mobile devices? How are MedStar Health
  and Unifi meeting those challenges?
• Why dont the companies in this case use some of
  the thousands of software packages available for
  their wireless mobile devices? What are the
  advantages and limitations of this approach?

6
Real World Internet Activity

• Use the Internet to research wireless mobile
  devices like the Sprint PPC-6700. Do an analysis
  of the desirable features and limitations of the
  smart wireless mobile device you would most be
  willing to use in a work situation. Defend your
  choice.

7
Real World Group Activity

• While Best Buy has standardized on the Sprint
  PPC-6700 for its Geek Squad, MedStar Health lets
  their medical practitioners pick their own
  devices. Should companies mandate a standard
  wireless mobile device for their employees?
• Discuss the pros and cons of this question then
  formulate and defend a proposed solution.

8
Network Concepts

• Network
• An interconnected chain, group or system
• Number of possible connections on a network is N
  (N-1)
• Where N number of nodes (points of connections
  on the network)
• Example, if there are 10 computers on a network,
  there are 10 9 90 possible connections

9
Metcalfes Law

• The usefulness of a network equals the square of
  the number of users
• On a small network, a change in technology
  affects technology only
• On a large network like the Internet, a change in
  technology affects social, political and economic
  systems

10
Telecommunications

• Telecommunications
• Exchange of information in any form (voice, data,
  text, images, audio, video) over networks

11
Trends in Telecommunications
12
Open Systems

• Information systems that use common standards for
  hardware, software, applications and networks
• Internet networking technologies are a common
  standard for open systems
• Connectivity
• Ability of networked computers to easily access
  and communicate with each other and share
  information
• Interoperability
• The ability of an open system to enable end user
  applications to be accomplished using different
  varieties of computer systems, software packages,
  and databases provided by a variety of
  interconnected networks

13
Middleware

• Any programming that serves to glue together
  two separate programs

14
Digital Network Technologies

• Rapid change from analog to digital network
  technologies
• Analog voice-oriented transmission, sound waves
• Digital discrete pulse transmission
• Digital allows
• Higher transmission speed
• Larger amounts of information
• Greater economy
• Lower error rates
• Multiple forms of communications on same circuit

15
Internet2

• Next generation of the Internet
• High-performance network
• In use at 200 universities, scientific
  institutions, communications corporations

16
Business Value of Telecommunication Networks
17
The Internet

• Over 46 million servers (2004)
• 710 945 million users (2004)
• No central computer system
• No governing body
• No one owns it

18
Internet Service Provider

• ISP
• A company that specializes in providing easy
  access to the Internet
• For a monthly fee, you get software, user name,
  password and access
• ISPs are connect to one another through network
  access points

19
Popular uses of the Internet
20
Using the Internet for business
21
Business value of the Internet
22
An Intranet

• A network inside an organization
• That uses Internet technologies (such as Web
  browsers and servers, TCP/IP protocols, HTML,
  etc.)
• To provide an Internet-like environment within
  the organization
• For information sharing, communications,
  collaboration and support of business processes
• Protected by security measures
• Can be accessed by authorized users through the
  Internet

23
Enterprise Information Portal
24
Extranet

• Network links that use Internet technologies
• To connect the Intranet of a business
• With the Intranets of its customers, suppliers or
  other business partners

25
Extranet Uses
26
Case 2 Metric MultistandardComponents
Corporation

• A secure network foundation can improve a small
  companys operational efficiency, secure
  sensitive data, contain costs, and enhance
  employee connectivity and customer
  responsiveness.
• It allows customers to securely track their
  orders in real time over the Web
• It empowers customer-service agents with detailed
  account information to answer their customers
  enquiry
• It can provide easy, inexpensive
  videoconferencing for remote workers, vendors,
  and customers.

27
Case Study Questions

• What were the most important factors contributing
  to MMCCs success with its new, secure,
  self-managed network? Explain the reasons for
  your choices.
• What are some of the business benefits and
  challenges of self-managed and externally managed
  networks?
• Which type of network management would you advise
  small-to-medium business firms to use? Explain
  the reasons for your recommendation.

28
Real World Internet Activity

• Use the Internet to discover more about the
  telecommunications products and services and
  current business performance and prospects of
  Cisco Systems and Hi-Link and some of their many
  competitors in the telecom industry.
• Which telecom hardware and software company and
  IT consulting firm would you recommend to a
  small-to-medium business with which you are
  familiar? Explain your reasons to the class.

29
Real World Group Activity

• In telecommunications network installation and
  management, as in many other business situations,
  the choice between do it yourself and let the
  experts handle it is a crucial business decision
  for many companies.
• Debate this choice for small-to-medium
  businesses. See if you can agree on several key
  criteria that should be considered in making this
  decision, and report your conclusions to the
  class.

30
Telecommunications network

• Any arrangement where a sender transmits a
  message to a receiver over a channel consisting
  of some type of medium

31
Telecommunications network components

• Terminals any input/output device that uses
  networks to transmit or receive data
• Telecommunications Processors devices that
  support data transmission and reception
• Telecommunications Channels media over which
  data are transmitted and received
• Computers all sizes and types
• Telecommunications Control Software programs
  that control telecommunications activities

32
Telecommunications network model
33
Wide Area Network (WAN)

• Telecommunications network that covers a large
  geographic area

Source Courtesy of Cisco Systems Inc.
34
Local Area Network (LAN)

• Connect computers within a limited physical area
  such as an office, classroom, or building

35
Virtual Private Networks (VPN)

• A secure network that uses the Internet as its
  backbone but relies on firewalls, encryption and
  other security
• A pipe traveling through the Internet

36
VPN
37
Client/Server networks

• Clients End user personal computers or networked
  computers
• Interconnected by LANs
• Servers manage networks
• Processing shared between clients and servers

38
Client/Server Network
39
Network Computing

• Networks are the central computing resource of
  the organization
• Thin clients network computers and other clients
  provide a browser-based user interface

40
Peer-to-peer networks

• Networks that connect from one PC to another PC
• Common use is the downloading and trading of files

41
Peer-to-Peer Network
42
Telecommunications Media

• Twisted-pair wire
• Ordinary telephone wire
• Copper wire twisted into pairs

Source Phil Degginger/Getty Images.
43
Telecommunications Media

• Coaxial cable
• Sturdy copper or aluminum wire wrapped with
  spacers to insulate and protect it

Source Ryan McVay/Getty Images.
44
Telecommunications Media

• Fiber-optic cable
• One or more hair-thin filaments of glass fiber
  wrapped in a protective jacket

Source CMCD/Getty Images.
45
Problem of The Last Mile

• Network providers use fiber optic to provide
  backbone
• But houses are connected to the backbone via
  twisted-pair
• Cannot get the benefit of the faster, better
  technology

46
Wireless Technologies

• Terrestrial microwave
• Earthbound microwave systems that transmit
  high-speed radio signals in a line-of-sight path
• Between relay systems spaced approximately
  30-miles apart
• Communications satellites
• Satellite serves as relay stations for
  communications signals
• Uses microwave radio signals

47
Wireless Technologies

• Cellular and PCS telephone and pager systems
• Divide the geographic area into small areas or
  cells
• Each cell has transmitter or radio relay antenna
  to send message from one cell to another
• Wireless LANs
• Radio signals within an office or building
• Connect PCs to networks
• Bluetooth
• Short-range wireless technology
• To connect PC to peripherals such as printer

48
Wireless Web

• Connect portable communications devices to the
  Internet

49
Telecommunications Processors

• Modems
• Convert digital signals from a computer into
• Analog frequencies that can be transmitted over
  ordinary telephone lines

50
Comparing modem and other technologies
51
Internetwork Processors

• Switch makes connections between
  telecommunications circuits in a network
• Router intelligent communications processor
  that interconnects networks based on different
  protocols
• Hub a port switching communications processor
• Gateway connects networks using different
  communications architectures

52
Communications Processors
53
Telecommunications Processors

• Multiplexer
• Allows a single communications channel to carry
  simultaneous data transmissions from many
  terminals

54
Telecommunications Software

• Used by servers and other computers to manage
  network performance
• Network Operating Systems
• Middleware

55
Network management functions

• Traffic Management manage network resources and
  traffic to avoid congestion and optimize service
  levels to users
• Security provide authentication, encryption,
  firewall, auditing and enforcement
• Network Monitoring troubleshoot and watch over
  the network, informing network administrators of
  potential problems before they occur
• Capacity Planning survey network resources and
  traffic patterns and users needs to determine
  how best to accommodate the needs of the network
  as it grows and changes

56
Network Topologies

• Topology structure of a network
• Star ties end user computers to a central
  computer
• Ring ties local computer processors together in
  a ring on a relatively equal basis
• Bus local processors share the same
  communications channel

57
Network Topologies
58
Network Architectures Protocols

• Protocol standard set of rules and procedures
  for the control of communications in a network
• Network Architecture
• Master plan of standard protocols, hardware,
  software and interfaces between end users and
  computer systems
• Goal of promoting an open, simple, flexible, and
  efficient telecommunications environment

59
OSI TCP/IP Models

• Open Systems Interconnection (OSI) Model
• A seven-layer model that serves as a standard
  model for network architectures
• Model for how messages should be transmitted
  between two points in a network
• Each layer adds functions
• Transmission Control Protocol / Internet Protocol
  (TCP/IP)
• A five layer telecommunications protocol used by
  the Internet

60
OSI TCP/IP Models
61
Internet Telephony

• Using an Internet connection to pass voice data
  using IP
• Voice over IP (VoIP)
• Skips standard long-distance phone charges

62
Bandwidth

• Bandwidth
• Frequency range of a telecommunications channel
• Determines transmission rate
• Classified in bits per second (bps)
• Transmission Rates
• Narrow-band low-speed
• Broadband high-speed

63
Transmission Speeds
64
Switching Alternatives

• Circuit Switching
• Switch opens a circuit to establish a link
  between a sender and receiver
• it remains open until the communication session
  is completed
• Packet Switching
• Break messages into groups called packets
• Transmit packets separately

65
Network Interoperability

• Ensure that anyone anywhere on one network
• Can communicate
• With anyone anywhere on another network
• Telecommunications as discussed in this chapter
  wouldnt be possible without interoperability

66
Case 3 SAIC, Hewlett-Packard, GE, and Others
The Business Case for Wireless Sensor Networks

• Wireless sensor devices, or motes, can detect
  changes in temperature, pressure, moisture,
  light, sound, or magnetism and report the
  information using wireless radio.
• They are a giant leap compared to traditional
  sensors.
• Motes cost about 100 each and are much cheaper
  to install.
• The worldwide market for wireless sensors is
  expected to grow from 100 million in 2005 to
  more than 1 billion by 2009.

67
Case Study Questions

• What are some of the business benefits associated
  with using wireless networks to collect and
  transmit data?
• What are some of the challenges faced by this use
  of wireless technologies? What solutions can you
  offer?
• The use of wireless networking as described in
  the case is both innovative and functional. What
  other business uses can you envision for this
  approach?

68
Real World Internet Activity

• The companies mentioned in the caseIntel, IBM,
  SAIC, and GEare all familiar names often
  associated with innovative approaches to
  technology.
• Using the Internet, see if you can find examples
  of other companies that have found ways in which
  to apply mote wireless technology to business
  needs.

69
Real World Group Activity

• One way of describing this use of wireless
  technologies is that it represents a marriage
  between RFID (we learned about these devices in
  Chapter 3) and wireless networking. This
  combination of enabling technologies results in
  an entirely new way of accomplishing an old task.
  
• Brainstorm other combinations of existing
  technologies to create new approaches to existing
  business activities.