Chapter 9
1 / 26

Chapter 9 - PowerPoint PPT Presentation

  • Updated On :

Chapter 9 . Networking and Telecommunication. Topics. Linking Up: Network Basics Electronic Mail, Teleconferences, and Instant Messages: Interpersonal Computing Converging Communication Technologies: From Messages to Money. Linking Up: Network Basics.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Chapter 9' - aizza

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Chapter 9 l.jpg

Chapter 9




Topics l.jpg

  • Linking Up: Network Basics

  • Electronic Mail, Teleconferences, and Instant Messages: Interpersonal Computing

  • Converging Communication Technologies: From Messages to Money

Linking up network basics l.jpg
Linking Up: Network Basics

  • A computer network is any system of two or more computers that are linked together.

  • How do networks impact systems?

    • People share computer hardware, thus reducing costs

    • People share data and software programs, thus increasing efficiency and production

    • People work together in ways that are otherwise difficult or impossible

Basic network anatomy l.jpg
Basic Network Anatomy

  • The three basic components of a network:

    • Hardware

    • Software

    • People

  • Direct Connection--one of many computers linked in an office

  • Remote Access--computer linked to a network through a phone line, television cable system or satellite link

The network interface l.jpg
The Network Interface

  • Anetwork interface card(NIC) permits direct network connection

  • It adds an additional serial port to the computer

  • The network interface card controls the flow of data between the computer’s RAM and the network cable.

Communication la modem l.jpg
Communication á la Modem

  • Amodemis a hardware device that connects a computer’s serial port to a telephone line (for remote access).

  • May be internal on the system board or external modem sitting in a box linked to a serial port.

  • Modem transmission speed is measured in bits per second (bps) and generally transmit at 28,000 bps to 56.6K bps

Conversion of signals l.jpg
Conversion of Signals

Computers send digital signals. The modem (modulator/demodulator) converts the digital signals to analog so that the message can be transmitted through telephone lines.

Conversion of signals8 l.jpg
Conversion of Signals

The modem (modulator/demodulator) converts the analog signals back to digital signals that are understood by the computer

Faster modem alternatives broadband technologies l.jpg
Faster Modem Alternatives:Broadband Technologies

  • DSL - Digital Subscriber Line

    • Uses standard phone lines

    • Makes use of unused frequencies in phone lines

    • Speed dependent on distance from main office

  • Cable Modems

    • Uses cable television networks

    • Makes use of unused channel frequencies

    • Speed dependent on number of users on network at a given time

Networks near and far l.jpg
Networks Near and Far

Local-area network (LAN)

  • Computers are linked within a building or cluster of buildings.

  • Each computer and peripheral is an individual node on the network.

  • Nodes are connected by cables which may be either twisted pair (copper wires) or coaxial cable.

Networks near and far11 l.jpg
Networks Near and Far

Wide-area network (WAN)

  • A network that extends over a long distance.

  • Each network site is a node on the network.

  • Data transmitted over common pathways called abackbone.

Wide area networks l.jpg
Wide-Area Networks

  • Made up of LANs linked by phone lines, microwave towers, and communication satellites.

  • Bridges, routers, and gateways are hardware devices that pass messages between networks.

Communication software l.jpg
Communication Software

  • Protocol - set of rules for the exchange of data between a terminal and a computer or between two computers

  • Communication softwareestablishes a protocol that is followed by the computer’s hardware

Communication software14 l.jpg
Communication Software

  • Many forms:

    • Network operating system(NOS)- handles communications between many workstations

    • Client/server model- one or more computers act as dedicated serves and all the remaining computers act as clients

    • Peer-to-peer model- every computer on the network is both client and server

    • Many networks arehybrids, using features of the client/server and peer-to-peer models

Client server model l.jpg
Client/Server Model

Server software responds to client requests by providing data

Client software sends requests from the user to the server

The network advantage l.jpg
The Network Advantage

  • Why do people use networks?

    • To share computer resources (hardware and software)

    • To support working together in new and different ways

Lotus Notes is a groupware application that facilitates information sharing and workgroup collaboration.

E mail mail teleconferences and im interpersonal computing l.jpg
E-mail Mail, Teleconferences, and IM: Interpersonal Computing

  • Electronic mail, teleconferencing and instant messaging allow communications between two or more people.

  • Meetings can be held in real-time (synchronous) or delayed (asynchronous)

  • Chat rooms are examples of synchronous communications; bulletin boards are examples of asynchronous communications.

The postal alternative l.jpg
The Postal Alternative Computing

  • E-mail is fast.

  • E-mail doesn’t depend on location.

  • E-mail facilitates group communication.

  • E-mail messages are digital data that can be edited and combined with other computer-generated documents.

Advantages of e mail and teleconferencing l.jpg
Advantages of E-mail and Teleconferencing Computing

  • On-line communication is less intrusive.

  • On-line communication allows time shifting.

  • Teleconferences and e-mail promotes teleworking.

  • Teleconferences and e-mail emphasize the message over the messenger.

On line issues for e mail and teleconferencing l.jpg
On-line Issues for E-mail and Teleconferencing Computing

  • Vulnerable to machine failures, network glitches, human errors and security

  • Threat to privacy

  • E-mail forgery

  • Information overload

  • Missing “human” elements of communication

Converging communication technologies from messages to money l.jpg
Converging Communication Technologies: From Messages to Money

  • On-line Information Services

  • Fax Machines and Fax Modem

  • Voice Mail and Computer Telephony

  • Global Positioning System

  • Video Teleconferencing

  • E-Money

Physical media for networks l.jpg
Physical Media for Networks Money

Networks are built on physical media.

  • Twisted pair (Category 5)

  • Twisted pair (Traditional)

  • Coaxial Cable

  • Fiber optic

  • Wireless/infrared

  • Wireless/radio

    What affects network performance?

  • Bandwidth and maximum operating distance

“Never in history has distance meant less.”

Alvin Toffler

Bandwidth l.jpg
Bandwidth Money

  • The amount of information that can be transmitted in a given amount of time

  • Impacted by:

    • Physical media that make up the network

    • Amount of network traffic

    • Software protocols of the network

    • Type of network connection

Fiber optic cables l.jpg
Fiber Optic Cables Money

  • Fiber optic cables are replacing aging cooper lines with high-capacity fiber optic cables.

  • They use light waves to carry information at blinding speeds.

  • A single fiber optic cable can transmit half a gigabit (500 million bits) per second, replacing 10,000 standard telephone cables.

  • Data is transmitted more accurately and reliably.

Digital communication comes home l.jpg
Digital Communication Comes Home Money

  • Digital communication lines will radically change services to our homes.

  • Multi-person video phone conversations, universal e-mail, customized digital newspapers, automatic utility metering and unlimited entertainment options