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Telecommunications and Networking. MIS 503 - Management Information Systems MBA Program. A Significant Underestimation. “This ‘telephone’ has too many shortcomings to be seriously considered as a means of communication. the device is inherently of no value to us.”

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telecommunications and networking

Telecommunications and Networking

MIS 503 - Management Information Systems

MBA Program

a significant underestimation
A Significant Underestimation

“This ‘telephone’ has too many shortcomings to be seriously considered as a means of communication. the device is inherently of no value to us.”

Western Union internal memo, 1876.



Networking –

the electronic linking of geographically dispersed devices

Telecommunications –

communications (voice and data) at a distance

Page 97-98


What is communication?

  • The Romans used the Latin word communicare when they meant "to make common, to share, or to impart.”
  • Communication is the sharing of information or messages between two or more entities.

Elements of a Communication System

  • Source - the originator of the message, whether it is a person or machine.
  • Transmitter - the equipment that modifies the message (either data or voice) into the form required for transmission.
  • Communications channel - the means of carrying the signal from the source to the destination.

Elements of a Communication System

  • Transmission media - may be physical, like a copper wire or fiber optic cable, or atmospheric, like radio waves.
  • Receiver - is the device that captures the message from the communications channel and converts it into a form that the person or machine at the destination can understand.
  • Destination - the person or machine to whom the message is directed


Analog and Digital Signals

Figure 4.1 Use of Modem in Analog Network

Page 99

types of signals
Types of Signals
  • Analog signal- a continuous fluctuation over time between high and low voltage.
  • Digital signal- discrete voltage state - either high or low.
transmission modes
Transmission Modes
  • Data can flow between telecommunication devices in three ways:
    • Simplex - the data can flow only in one direction.
    • Half-Duplex - the data can flow in both directions, but it can only flow in one direction at any point in time.
    • Full-Duplex - data can flow in both directions at the same time.


Transmission Media

Typical Speeds

Table 4.2 Telecommunications Transmission Speeds

data transmission
Data Transmission
  • Asynchronous transmission - the data is sent in packages of characters, one character at a time.
    • Each character set includes a parity bit surrounded by start and stop bits. The parity bit is used for error checking.
  • Synchronous transmission - data is sent in packages of more than one character at a time with each block sandwiched between a header byte and a trailer byte, called flags.


Topology of Networks

Figure 4.5 Network Topologies


More Complex Networks

Figure 4.6 vBNS+ Network Map



Local Area Networks

  • LAN Topologies and Standards
    • Contention bus design … IEEE 802.3
    • Token bus design … IEEE 802.4
    • Token ring design … IEEE 802.5
    • Wireless design … IEEE 802.11


Types of Networks

  • Backbone network terminology:
    • Bridge – connects two LANs using same protocol
    • Router (gateway) – connects two or more LANs that may use different protocols
    • Switch – connects more than two LANs using the same protocols
microwave and satellite transmission
Microwave and Satellite Transmission
  • A communications satelliteis a microwave station placed in outer space.
    • Satellites don’t “bounce” the microwave signal; rather, the signal is received and then rebroadcast at a different frequency.
    • Satellites can broadcast over long distances.
a classic case of miscalculation iridium
A Classic Case of MiscalculationIridium
  • Iridium communications
    • Launched November 1, 1998
    • Went into Chapter 11 bankruptcy on August 13, 1999
    • Why?
      • Miscalculated competition from cellular
      • Development costs were high
      • Prices were too high
      • Technology was awkward and limited
      • The project was mismanaged
    • Visit for more informaiton
other transmission options
Other Transmission Options
  • Cellular transmission– Well, you know about this one…
mobile phone generations
Mobile Phone Generations
  • 1G: The first generation of wireless technology
    • used analog communication
    • designed for voice communication
  • 2G: The second generation of digital wireless technology
    • Uses digital circuit switched transmission protocols
    • Capable of providing voice/data/fax transfers, albeit at low data rates
    • SMS was introduced in 1994 and became a popular tool associated with GSM (Global System for Mobile communications)

Mobile Phone Generations (cont.)

  • 2.5G: Interim wireless technology that has greater bandwidth
    • CDMA2000 1x (Code Division Multiple Access) and GPRS (general packet radio service)
    • Uses packet switching, which offers high data transfer rates (e.g., up to 307 kbit/s) compared to the circuit switching of GSM and other 2G networks

Mobile Phone Generations (cont.)

  • 3G: The third generation of digital wireless technology
    • For example, UMTS and CDMA2000 1xEV-DO
    • High data transfer rates (2.4Mbit/s)
    • It has the potential to support rich media such as video and graphics

Mobile Phone Generations (cont.)

  • 4G: The next generation of wireless technology
    • Very high data transfer rates (20 Mbps)
    • In the context of mobile phones, it is expected to be available by 2010
    • 4G also refers to the integration of mobile phones, Wi/Fi networks, and other components of a pervasive network

Wireless Networking Standards

  • 802.11 - IEEE’s Radio Frequency Wireless networking standard committee.
  • 802.11b - uses direct sequence spread spectrum (DSSS) signaling. Also used the 2.4 - 2.4835 GHz frequency range and separates it into 14 overlapping 22-MHz channels.
  • 802.11g - designed to be just as affordable as 802.11b while increasing its maximum capacity from 11 Mbps through different encoding techniques.
  • 802.11a - uses multiple frequency bands in the 5 GHZ range. Like 802.11g, 802.11a provides a maximum throughput of 54 Mbps.
  • WiMAX is an acronym for Worldwide Interoperability for Microwave Access
    • IEEE 802.16d
  • WIMAX improves upon the limitations of Wi-Fi by providing increased bandwidth and range and stronger encryption
  • Applications
    • An alternative to cable and DSL for last mile
    • Connecting Wi-Fi hotspots
    • high-speed mobile data services


  • A mobile wireless networking standard that uses direct sequence spread spectrum (DSS) signaling in the 2.4 GHz band to achieve a maximum throughput of less than 1 Mbps.
  • Designed to be used on small networks composed of personal communications devices, also known as personal area networks.
significant quotes
Significant Quotes

“No sensible man would transact his affairs by a means of communication such as Bell’s telephone.”

Western Union Board of Directors letter to shareholders - - October 1876.

The Americans have need of the telephone, but we do not. We have plenty of messenger boys.

Sir William Preece, chief engineer of the British Post Office, 1876

k ey e lements of t elecommunications and n etworking
  • The Internet
    • Network of networks that use the TCP/IP protocol
    • Contain gateways to computers that do not use TCP/IP
    • Provides four basic functions:
      • Electronic mail
      • Remote login
      • Discussion groups
      • Sharing of data resources

Types of Networks

Page 117-118


Page 118

Table 4.4 Internet Applications

k ey e lements of t elecommunications and n etworking1
  • Internet access services:
    • Digital subscriber line (DSL) – service offered by telephone companies using copper wire already installed in homes … moving data over wires without disturbing voice traffic
    • Cable modem – connection obtained from cable TV company using existing home coaxial cable
    • Satellite – most expensive, but may be only option for customers in rural areas

DSL, Cable Modem, and Satellite

k ey e lements of t elecommunications and n etworking2


  • Intranet–
    • a network operating within an organization that uses the TCP/IP protocol
k ey e lements of t elecommunications and n etworking3
  • Internet2–
    • not-for-profit consortium of over 200 universities, working with over 60 technology companies and the U.S. government, to develop and deploy advanced network applications and technologies
k ey e lements of t elecommunications and n etworking4
  • Primary goals of Internet2:
    • Create a leading-edge network capability for the national research community
    • Enable revolutionary Internet applications based on a much higher-performance Internet that we have today
    • Ensure the rapid transfer of new network services and applications to the broader Internet community
k ey e lements of t elecommunications and n etworking5

Network Protocols

  • Protocol–
    • agreed-upon set of rules governing communication among layers or levels of a network
major telecommunications laws
Major Telecommunications Laws
  • Graham Act, 1921
    • Exempted telephone companies from antitrust laws
  • Communications Act of 1934
    • legislation which created the Federal Communications Commission
  • AT&T Consent Decree of 1956
    • AT&T and the US Justice department agree on a consent decree to end an antitrust suit against AT&T in 1949
  • Carterfone Decision of 1968
    • allowed other businesses to attach telephones, equipment and business switchboards to the Bell network
  • MCI Decision
    • FCC decree in 1969 that granted MCI Communications Inc., as well as any other company, the right to offer long distance service to customers and to connect to AT&T's network
  • Modified Final Judgment and Divestiture, 1984
    • Split up the Bell Network
  • The Telecommunications Act of 1996
the telecommunications act of 1996
The Telecommunications Act of 1996
  • The Telecommunications Act of 1996 was the first major overhaul of United States telecom policy in nearly 62 years. The focus of the Act was to enhance competition
  • The legislation regulates:
    • Broadcasting by over-the-air television and radio stations;
    • cable television operators;
    • satellite broadcasters;
    • Wireline telephone companies (local and long distance), wireless telephone companies, and others.
technology convergence





Technology Convergence

Voice Over IP (VoIP)

  • The use of packet-switched networks and the TCP/IP protocol suite to transmit voice conversations.
  • Reasons for implementing VoIP may include:
    • To improve business efficiency and competitiveness
    • To supply new or enhanced features and applications
    • To centralize voice and data network management
    • To improve employee productivity
    • To save money

VoIP and IP Telephones

  • Popular features unique to IP telephones include:
    • Screens on IP telephones can act as Web browsers, allowing a user to open HTTP-encoded pages and, for example, click a telephone number link to complete a call to that number.
    • IP telephones may connect to a user’s personal digital assistant (PDA) through an infrared port, enabling the user to, for example, view his phone directory and touch a number on the IP telephone’s LCD screen to call that number.
    • If a line is busy, an IP telephone can offer the caller the option to leave an instant message on the called party’s IP telephone screen.

Communication Technology

Audio Communication

Video Conferencing

Synchronous Chat

Project Management


Personal Information Management

Group Support Systems

Data Warehouses

Internet Search Engines

Spreadsheet Analysis Tools


Decision Support Technology

Information Access Technology

Technologies for Virtual Teams

collaboration enabling tools groupware
Collaboration-Enabling Tools:Groupware
  • Groupware: Software products that support collaboration, over networks, among groups of people who share a common task or goal
  • Provide a way for groups to share resources and opinions
collaboration enabling tools group decision support systems gdss
Collaboration-Enabling Tools: Group Decision Support Systems (GDSS)
  • Virtual meetings:Online meetings whose members are in different locations, frequently in different countries
  • Group decision support system (GDSS): An interactive computer-based system that facilitates the solution of semistructured and unstructured problems by a group of decision makers
collaboration enabling tools gdss cont
Collaboration-Enabling Tools: GDSS (cont.)
  • Major characteristics of a GDSS
    • Its goal is to support the process of group decision makers by providing automation of subprocesses using information technology tools
    • It is a specially designed information system
    • It encourages generation of ideas, resolution of conflicts, and freedom of expression
collaboration enabling tools gdss cont1
Collaboration-Enabling Tools: GDSS (cont.)
  • GDSSs improve the decision-making process by:
    • providing structure to the planning process
    • support parallel processing of information and idea generation
    • make larger meetings possible
collaboration enabling tools teleconferencing
Collaboration-Enabling Tools:Teleconferencing
  • Teleconferencing:The use of electronic communication that allows two or more people at different locations to have a simultaneous conference
  • Video teleconference:Virtual meeting in which participants in one location can see participants at other locations on a large screen or a desktop computer
collaboration enabling tools teleconferencing1
Collaboration-Enabling Tools:Teleconferencing
  • Data conferencing: Virtual meeting in which geographically dispersed groups work on documents together and to exchange computer files during videoconferences
  • Web conferencing is conducted on the Internet
    • few as two and as many as thousands of people
    • allows users to simultaneously view something
    • interaction takes place via messaging or a simultaneous phone teleconference
    • is much cheaper than videoconferencing because it runs on the Internet
  • An integrated portfolio of collaboration and communication services designed to connect people, information, processes, and systems both within and beyond the organizational firewall. (MS Website)
    • A virtual desktop
    • A collaboration space
    • Shared workspace
    • Communication portal for teams
unique opportunities
Unique Opportunities

“That is the essence of virtualization: rather than simply re-creating in digital form the physical thing we know as a letter, e-mail reinvents and vastly enhances letter-writing. Unbound by barriers of time and space and endowed with new powers, the electronic letter does something new altogether. The same sort of thing happens when business, the arts, or government are reborn in digital form.”

John Verity, Business Week, 1994

looking into the future
Looking into the Future

“Computers are getting smaller and smaller. You can expect to have on your wrist tomorrow what you have on your desk today, what filled a room yesterday.”

Nicholas Negroponte , Being Digital

Today’s average consumers wear more computing power on their wrists than existed in the entire world before 1961.


planning for security and control
Planning for Security and Control
  • In today’s net-enabled environment, an increasingly important part of IT planning involves planning to control and secure the IT resource
control systems
Control Systems
  • The components of control systems are
    • Standards for performance
    • Sensory determination of actual conditions
    • Comparison of standard with actual conditions
    • Compensatory action if the deviation is too great
when there are failures of control
When there are Failures of Control
  • Examples of control breakdowns
    • Worldcom
    • Qwest
    • Global Crossing
      • What caused these? Probably, it was in part the reward systems for senior managers that consisted of stock options. Managers were rewarded for inflating the bottom line.
  • IS has an important role to play in strengthening control systems
    • Audits
    • Monitoring
    • Information dissemination
    • Reporting
vulnerability of systems where does control fail
Vulnerability of Systems: Where Does Control Fail?
  • Errors in and intrusion of the operating system
  • Errors in application programs
  • Problems with database security
  • Lack of network reliability and security
  • Problems with adequate control of manual procedures
  • Failure of management to maintain proper organizational control
  • Open networks and connectivity
  • Misuse or mistakes made by users
control in the organization controls can be created through
The structure of the organization

Decentralized or centralized


Management committee


Direct supervision

Routine audits

Establish and enforce standards and procedures

Develop a plan and policy for managing database resources

Data Backup/Recovery

Data Concurrency Management

Data Security

Control in the Organization: Controls can be created through…
a key requirement for control is establishing it security
A Key Requirement for Control is Establishing IT Security
  • Without security, the integrity of organizational IT resources will be at risk – therefore, security is everyone’s business
  • Security is an increasingly important issue because of an increasing number of threats
    • According to the statistics reported to CERT/CC over the past several years (CERT/CC 2003) the number of cyber attacks grew from approximately 22,000 in 2000 to 137,529 2003
    • According to the 2004 E-Crime Watch Survey, 43% of respondents report an increase in e-crimes and intrusions versus the previous year and 70% reported at least one e-crime or intrusion was committed against their organization
security concepts
Security Concepts
  • Authentication:The process by which one entity verifies that another entity is who they claim to be
  • Authorization:The process that ensures that a person has the right to access certain resources
  • Confidentiality:Keeping private or sensitive information from being disclosed to unauthorized individuals, entities, or processes
  • Integrity:Being about to protect data from being altered or destroyed in an unauthorized or accidental manner
  • Confidentiality:Keeping private or sensitive information from being disclosed to unauthorized individuals, entities, or processes
  • Nonrepudiation:The ability to limit parties from refuting that a legitimate transaction took place, usually by means of a signature

Types of Threats and Attacks

  • Nontechnical attack:An attack that uses chicanery to trick people into revealing sensitive information or performing actions that compromise the security of a network

Types of Threats and Attacks (cont.)

  • Social engineering:A type of nontechnical attack that uses social pressures to trick computer users into compromising computer networks to which those individuals have access

Types of Threats and Attacks (cont.)

  • Multiprong approach used to combat social engineering:
    • Education and training
    • Policies and procedures
    • Penetration testing

Types of Threats and Attacks (cont.)

  • Technical attack: An attack perpetrated using software and systems knowledge or expertise

Types of Threats and Attacks (cont.)

  • Denial-of-service (DoS) attack:An attack on a Web site in which an attacker uses specialized software to send a flood of data packets to the target computer with the aim of overloading its resources

Types of Threats and Attacks (cont.)

  • Distributed denial-of-service (DDoS) attack:A denial-of-service attack in which the attacker gains illegal administrative access to as many computers on the Internet as possible and uses these multiple computers to send a flood of data packets to the target computer

Types of Threats and Attacks (cont.)

  • Malware:A generic term for malicious software
    • The severity of virus attacks are increasing substantially, requiring much more time and money to recover
    • 85% of survey respondents said that their organizations had been the victims of e-mail viruses in 2002

Types of Threats and Attacks

  • Malware takes a variety of forms - both pure and hybrid
    • Virus: A piece of software code that inserts itself into a host, including the operating systems, to propagate; it requires that its host program be run to activate it
    • Worm: A software program that runs independently, consuming the resources of its host in order to maintain itself and is capable of propagating a complete working version of itself onto another machine
    • Macro virus or macro worm: A virus or worm that is executed when the application object that contains the macro is opened or a particular procedure is executed
    • Trojan horse: A program that appears to have a useful function but that contains a hidden function that presents a security risk
cert recommendations for governing organizational security
CERT: Recommendations for Governing Organizational Security
  • Questions to ask:
    • What is at risk?
    • How much security is enough
    • How should an organization …
      • Develop policies on security
      • Achieve and sustain proper security

The CERT recommendations are derived from a report written by Julia Allen entitled Governing for Enterprise Security, which may be found at

cert recommendations for governing organizational security1
CERT: Recommendations for Governing Organizational Security
  • What is at risk?
    • Trust that the public has in your organization
    • Reputation and brand
    • Shareholder value
    • Market confidence
    • Regulatory compliance
      • Fines
      • Jail time
    • Market share
    • Customer privacy
    • Ongoing, uninterrupted operations
    • Morale of organizational members
cert recommendations for governing organizational security2
CERT: Recommendations for Governing Organizational Security
  • How Much Security is Enough?
    • “Management’s perspective needs to shift
cert recommendations for governing organizational security3
CERT: Recommendations for Governing Organizational Security
  • Good Security Strategy Questions
    • What needs to be protected?
      • Why does it need to be protected?
      • What happens if it is not protected?
    • What potential adverse consequences need to be prevented?
      • What will be the cost?
      • How much of a disruption can we stand before we take action?
    • How do we effectively manage the residual risk when protection and prevention actions are not taken?
cert recommendations for evolving the security approach2
CERT: Recommendations for Evolving the Security Approach
  • What Does Effective Security Look Like at the Enterprise Level?
    • It’s no longer solely under IT’s control
    • Achievable, measurable objectives are defined and included in strategic and operational plans
    • Functions across the organization view security as part of their job (e.g., Audit) and are so measured
    • Adequate and sustained funding is a given
    • Senior executives visibly sponsor and measure this work against defined performance parameters
    • Considered a requirement of being in business