Data Communication Systems Quiz

Module 6: Data Communication: Delivery Information Anywhere and Anytime

• Data communication involves transferring data between locations.
• It improves data collection and transmission flexibility, forming the basis of virtual organizations and e-collaboration.

Learning Objectives (1 of 2)

• Describe major data communication system applications.
• Explain the three major components of a data communication system.
• Describe the three major types of processing configurations.
• Explain the three types of networks.
• Describe the five main network topologies.

Learning Objectives (2 of 2)

• Explain important networking concepts (protocols, TCP/IP, routing, routers, client/server).
• Examine wireless and mobile technologies and networks in a business setting.
• Describe networking trends like Wi-Fi, WiMAX, and Bluetooth.
• Discuss the importance of wireless security and five related techniques.
• Summarize convergence and its business and personal applications.

Data Communication

• Electronic data transfer between locations.
• Enables information system delivery.
• Improves data collection and transmission flexibility.
• Forms the basis for virtual organizations.
• Facilitates e-collaboration.

Why Managers Need to Know about Data Communication (1 of 3)

• Enhances decision-maker efficiency and effectiveness.
• Enables organizations to use e-mail and electronic file transfer to boost productivity.

Why Managers Need to Know about Data Communication (2 of 3)

• Workplace effects of data communication technologies include:
  • Online employee training through virtual classrooms.
  • Updated employee information via online searches.
  • Facilitated lifelong learning through the internet.
  • Blurring work and personal boundaries.
  • Easier web and video conferencing.

Why Managers Need to Know about Data Communication (3 of 3)

• Managers should understand:
  • Basics of data communication and networking.
  • The internet, intranets, and extranets.
    • Wired and wireless networks
  • Network security issues and measures.
  • Organizational and social effects of data communication.
  • Globalization issues.
  • Applications of data communication systems.

Basic Concepts of a Data Communication System (1 of 2)

• Bandwidth: Amount of data transferred in a set time.
• Attenuation: Signal power loss during transmission.
• Broadband: Sending multiple data pieces simultaneously to increase transmission speed.

Basic Concepts of a Data Communication System (2 of 2)

• Narrowband: Voice-grade transmission channel with a maximum of 56,000 bps, limited information capacity.
• Protocols: Govern data communication, covering error detection, message length, and transmission speed.

Sender and Receiver Devices (1 of 2)

• Input/output device (thin client): Used for sending/receiving information, no processing power.
• Smart terminal: Performs specific processing tasks, not a full-featured computer.
• Intelligent terminal/workstation/personal computer: Performs processing without main computer support.

Sender and Receiver Devices (2 of 2)

• Netbook computer: Low-cost, diskless computer connecting to the internet or LAN, using server-based software.
• Minicomputers/mainframes/supercomputers: Process data and send/receive data from other devices.
• Smartphones: Feature-rich cell phones with built-in or external keyboards.

Modems (1 of 2)

• Devices connecting users to the internet.
• Short for modulator-demodulator.
• Not required for all internet connections.

Modems (2 of 2)

• Dial-up modem: Converts digital signals to analog for ordinary phone lines (rarely used today).
• Digital subscriber line (DSL): Offers high-speed digital service using ordinary phone lines.
• Cable modems: Utilize cable TV lines for internet access.

Communication Media

• Channels linking senders and receivers.
  • Conducted media (wired/guided): Provides physical signal transmission paths.
  • Radiated media (wireless): Uses antennas for air or water-based data transmission. Can be point-to-point or multipoint.
    • Examples include electrical conductors, light conductors, fiber optics, wires (STP & UTP), coaxial cables, radio frequencies, light frequencies, infrared, broadcast, spread spectrum, cellular, microwave, and satellite.

Processing Configurations

• Data communication systems are used in various configurations.
• Centralized, decentralized, and distributed are three established types.

Centralized Processing (1 of 2)

• Processing takes place on a single central computer.
• Used in early computer days due to limited data processing personnel and expensive hardware/software.

Centralized Processing (2 of 2)

• Advantage: Strong control over system operations and applications.
• Disadvantage: Less responsive to user needs.

Decentralized Processing

• Each user, department, or division has its own computer.
• Advantage: Responsive to user needs.
• Disadvantage: Difficulty coordinating organizational units, high cost due to multiple systems, and risk of duplicated efforts.

Distributed Processing (1 of 2)

• Combines centralized control with decentralized operations.
• Advantages: Access to unused processing power, ability to add/remove computer power as needed, greater flexibility over distance, better fault tolerance, and potential cost savings through resource sharing.

Distributed Processing (2 of 2)

• Disadvantages: Increased security and privacy challenges, potential incompatibility between different equipment, and more complex network management.

Open Systems Interconnection (OSI) Model (1 of 2)

• Seven-layer architecture for computer-to-computer data transmission.
• Standardizes network interactions.
• Layers (1-7): Physical, Data Link, Network, Transport, Session, Presentation, Application.

Open Systems Interconnection (OSI) Model (2 of 2)

• Application (Layer 7): Access point for applications to network services.
• Presentation (Layer 6): Formats message packets.
• Session (Layer 5): Establishes communication between computers
• Transport (Layer 4): Ensures message integrity and order.
• Network (Layer 3): Routes messages.
• Data Link (Layer 2): Controls the communication link..
• Physical (Layer 1): Defines physical communication methods.

Types of Networks (1 of 2)

• Network Interface Card (NIC): Hardware for facilitating network communication, often called an adapter card. Operates at the Physical and Data Link Layers (OSI).

Types of Networks (2 of 2)

• Local Area Network (LAN): Connects workstations and peripheral devices in close proximity.
• Wide Area Network (WAN): Covers vast distances, often spanning cities, states, or countries, owned and operated by several parties.
• Metropolitan Area Network (MAN): Designed for data communication among multiple organizations within a city or nearby areas.

Network Topologies

• Represents a network's physical layout (computers and cables).
• Common topologies:
  • Star
  • Ring
  • Bus
  • Hierarchical
  • Mesh.

Star Topology

• Central computer connects to other nodes.
• Advantages: Easy cabling modifications, centralized problem detection, and easy node addition.
• Disadvantages: Failure of the central computer disables the entire network, higher costs due to more cabling.

Ring Topology

• Each node connects to two neighboring nodes for one-way data transmission.
• Advantages: Requires less cable than a star topology.
• Disadvantages: Difficult to diagnose/modify issues and a single node failure can disrupt the entire network.

Bus Topology

• Nodes connected along a network segment.
• Advantages: Easy to extend and reliable, simple and relatively low-cost wirings, effective for steady traffic.
• Disadvantages: Fault diagnosis is difficult, network bottleneck can occur under high traffic conditions.

Hierarchical Topology (1 of 2)

• Combines computers with varying processing strengths across different organizational levels, often resembling a tree structure.
  • Used in traditional mainframe networks
• Mainframe (at top): Centralized computer.
• Front-end processors (FEPs): Second level to handle data requests.
• Controllers and multiplexers: Third level for controlling data transfers to peripheral devices.
• Peripheral devices: At the bottom.

Hierarchical Topology (2 of 2)

• Advantage: Offers strong network control and lower costs than star topology.
• Disadvantage: Network expansion may present problems, and congestion can occur at higher levels.

Mesh Topology

• All nodes are connected to each other.
• Advantage: Highly reliable, and if a few nodes fail, the rest of the network often remains operational.
• Disadvantage: Expensive and difficult to maintain and expand.

Major Networking Concepts

• Protocols: Agreed-upon methods for electronic device communication, dealing with hardware connections, data transmission, and file transfers. Protocols specify message packet formats between computers.
• TCP/IP: Industry-standard suite enabling interoperability among diverse platforms. TCP handles link establishment integrity and data flow, while IP handles packet forwarding based on network addresses.
• Routing: The process of deciding the best path to send data packets. Routing tables store network information and automatically determine routes through the network.
• Routers: Network connection devices facilitating network system connections and traffic management.
• Client/server model: Software on a local computer (client) requests information/services from a remote network computer (server); this model is characterized by scalability.

Client/Server Model (1 of 2)

• Software on the client computer requests information or services from the server, which responds with the data.
• The server acts as the remote source of the information or service.

Client/Server Model (2 of 2)

• Advantage: Scalability.
• Logic Levels: There are three levels of logic for client/server interaction:
  • Presentation: How data is presented to users.
  • Application: Logical processes, requests, etc., for the user.
  • Data management: Handles data storage, retrieval, etc.

Two-Tier Architecture

• The client communicates directly with the server.
• Advantages: Speed, ease of development.
• Disadvantages: Client modifications are needed when the application logic is changed.

N-Tier Architecture

• Distributes workload among multiple tiers.
• Advantages: Improved network performance.
• Disadvantages: Handling more network traffic and more complex software testing.

Wireless and Mobile Networks (1 of 2)

• Wireless network: Uses wireless instead of wired technology.
• Mobile network: Network operating on radio frequency (RF). Consists of radio cells each served by a fixed transmitter (cell site or base station), also known as a cellular network.

Wireless and Mobile Networks (2 of 2)

• Advantages: Mobility, ease of installation, low cost.
• Disadvantages: Limited throughput and range, in-building penetration problems, vulnerability to frequency interference, and security issues.

Wireless Technologies

• Wireless LANs (WLANs): Alternatives to wired LANs, covering limited areas with one owner.
• Wireless WANs (WWANs): Cover wider areas than WLANs.

Wireless Fidelity (Wi-Fi)

• Broadband wireless technology.
• Transmits over short distances (120-300 feet).
• Susceptible to interference and data interception.

Worldwide Interoperability for Microwave Access (WiMAX)

• Broadband wireless technology.
• Designed for wireless metropolitan area networks.
• Up to 30-mile range.
• Faster data rates than Wi-Fi.
• Disadvantages include interference, high cost, weather disruptions, and high power requirements.

Bluetooth

• Wireless technology.
• Short-range data transfer.
• Allows communication between devices like smartphones, laptops, computers, printers; used in personal area networks (PANs).
• Susceptible to data interception.

Mobile Networks

• Consists of a three-part architecture:
  • Base stations
  • Mobile telephone switching offices (MTSOs).
  • Subscribers (users).
• Technologies like TDMA and CDMA increase efficiency in cell communication.

Wireless Security

• Techniques include:
  • SSID (Service Set Identifier)
  • WEP (Wired Equivalent Privacy)
  • EAP (Extensible Authentication Protocol)
  • WPA (Wi-Fi Protected Access), WPA2, or 802.11i.

Convergence of Voice, Video, and Data (1 of 2)

• Convergence: Integrating voice, video, and data for multimedia decision-making.
• Technological innovation, changing market structures, and regulatory reform contribute to this convergence.
• Multimedia is used for communication and decision-making.

Convergence of Voice, Video, and Data (2 of 2)

• Applications include:
  • E-commerce
  • More entertainment options
  • Increased affordability of video and computer conferencing
  • Consumer products and services.

Summary (1 of 4)

• Data communication systems improve data collection and transmission efficiency and flexibility.
• Three major components of a data communication system are senders/receivers, modems/routers, and communication media (channels).
• Three processing configurations: centralized, decentralized, and distributed.

Summary (2 of 4)

• Three major network types: LANs, WANs, and MANs.
• Computers often link to networks through network interface cards (NICs).
• Network topologies like star, ring, bus, hierarchical, and mesh describe the physical layout.
• Important networking concepts include protocols, TCP/IP, routing, routers, and the client/server model.

Summary (3 of 4)

• Wireless and mobile networks have advantages like mobility, ease of installation, and low cost.
• Examples of wireless technologies are Wi-Fi, WiMAX, and Bluetooth.
• Wireless security methods include SSID, WEP, EAP, WPA, WPA2, or 802.11i.

Summary (4 of 4)

• Convergence integrates voice, video, and data for multimedia use in decision-making.
• Applications include e-commerce, entertainment, and video/computer conferencing.

Test your knowledge on data communication systems, devices, and networking concepts. This quiz covers topics such as data transmission rates, the role of modems, and wireless security techniques. Perfect for anyone studying information technology and communications.