Extended Learning Module E

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• Extended Learning Module E
• Network Basics
• A great module on your CD.

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Presentation Overview

• Peer-to-Peer Home Networks
• Internet Access
• Business Networks
• LANs, MANs, WANs, and Communications Media
• Communications Service Providers

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Introduction

• Computer network - two or more computers
  connected so that they can communicate with each
  other and share information, software, peripheral
  devices, and/or processing power.

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IntroductionBasic Principles of Networks

• Each computer must have a network card.
• A network has at least one connecting device.
• There must be communications media connecting the
  network hardware devices.
• Each computer must have software that supports
  the movement of information.

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Peer-to-Peer Home Network

• Peer-to-peer network - a network in which a small
  number of computers share hardware, software
  and/or information.

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Peer-to-Peer Home NetworkHome Network Components

• Network interface card (NIC) - an expansion card
  or a PC Card that connects your computer to a
  network and provides the doorway for information
  to flow in and out.

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Peer-to-Peer Home NetworkHome Network Components

• Ethernet card - the most common type of network
  interface card.

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Peer-to-Peer Home NetworkHome Network Components

• Network hub - a device that connects multiple
  computers into a network.
• Switch - a device that connects multiple
  computers into a network in which multiple
  communications links can be in operation
  simultaneously.

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Peer-to-Peer Home NetworkHome Network Components

• Router - a device that acts as a smart hub
  connecting computers into a network, and it also
  separates your network from any other network
  its connected to.

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Peer-to-Peer Home NetworkHome Network Components
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Peer-to-Peer Home NetworkHome Network Components

• Firewall - software and/or hardware that protects
  a computer or network from intruders.
• Cat 5, or Category 5 cable - a better-constructed
  version of the phone twisted-pair cable.

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Peer-to-Peer Home NetworkWireless Access to Your
Home Network

• Wireless network access point or wireless access
  point - a device that allows computers to access
  a wired network using radio waves.

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Peer-to-Peer Home NetworkWireless Access to Your
Home Network

• WiFi, Wireless Fidelity, or IEEE 802.11b - a way
  of transmitting information in wave form that is
  reasonably fast and is often used for notebooks.
• Bluetooth technology - provides entirely wireless
  connections for all kinds of communication
  devices.

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Peer-to-Peer Home NetworkHome Network with
Existing Phone Wiring

• Home PNA (Home Phone line Networking Alliance) -
  allows you to network your home computers using
  telephone wiring.
• PNA adapter card - an expansion card that you put
  into your computer to act as an doorway for
  information flowing in and out.

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Peer-to-Peer Home NetworkHome Network with
Existing Phone Wiring
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Internet Access

• Ways to Access the Internet at Home
• Telephone line and a telephone or dial-up modem.
• Telephone line and a Digital Subscriber Line
  (DSL) modem.
• Cable TV line and a cable modem.
• Satellite dish and a satellite modem.
• Provider that offers wireless connection for your
  notebook.

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Internet Access

• Broadband - a high-capacity telecommunications
  pipeline capable of providing high-speed Internet
  service.

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Internet Access Telephone or Dial-Up Connection

• Telephone modem - a device that connects your
  computer to your phone line so that you can
  access another computer or network.

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Internet Access Digital Subscriber Line (DSL)

• Digital Subscriber Line (DSL) - a high-speed
  Internet connection using phone lines, which
  allows you to use your phone for voice
  communications at the same time.

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Internet Access Cable Modem

• Cable modem - a device that uses your TV cable to
  deliver an Internet connection.

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Internet Access Internet over Satellite

• Satellite modem - a modem that allows you to get
  Internet access from a satellite dish.

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Internet Access Internet Access on Multiple
Computers

• Network address translator (NAT) swaps messages
  between the private, internal IP addresses, and
  the public IP address, when moving information
  between the Internet and network computers.

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Internet Access Wireless Internet Connection

• Wireless Internet service provider (wireless ISP)
  - does the same job as standard Internet service
  providers except that you dont need a wired
  connection for access.

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Internet Access Wireless Internet Connection

• Personal digital assistant (PDA) - a small
  hand-held computer that helps you surf the Web
  and perform simple tasks such as note taking,
  calendaring, appointment scheduling, and
  maintaining an address book.
• Palms and Handspring - run on the Palm Operating
  System
• PocketPCs - run on Pocket PC OS

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Business Networks

• Client/server network - a network in which one or
  more computers are servers and provide services
  to the other computers which are called clients.

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Business NetworksClient/Server A Business View

• Client/server networks differ according to three
  factors
• Where the processing for the presentation of
  information occurs.
• Where the processing of logic or business rules
  occurs.
• Where the data management component (DBMS) and
  information (database) are located.

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Business NetworksClient/Server A Business View
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Business NetworksClient/Server A Business View

• The Five Models of Client/Server
• Distributed Presentation
• The server handles almost all functions,
  including a major portion of the presentation.
• Remote Presentation
• The client handles all presentation functions.
• Distributed Logic
• The server handles all data management and the
  client handles all presentation formatting, and
  the logic processing is shared.

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Business NetworksClient/Server A Business View

• Remote Data Management
• The server handles data management only, and the
  client processes business rules and formats the
  presentation of results.
• Distributed Data Management
• The client handles all presentation formatting
  and business rule processing, and both the server
  and client share data management duties.

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Client/Server A Business View
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Business NetworksClient/Server A Physical View

• Communications protocol (protocol) - a set of
  rules that every computer follows to transfer
  information.

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LANs, MANs, WANs, and Communications
MediaClassification of Networks by Geographic
Distance

• Local area network (LAN) - covers a limited
  geographic distance, such as an office, building,
  or a group of buildings in close proximity to
  each other.
• Municipal area network (MAN) - covers a
  metropolitan area.
• Wide area network (WAN) covers a large
  geographic distances, such as a state, a country,
  or even the entire world.

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LANs, MANs, WANs, and Communications
MediaTelecommunications Media The Paths That
Carry Information

• Communications media - the paths, or physical
  channels, in a network over which information
  travels.
• Wired communications media - transmit information
  over a closed, connected path.
• Wireless communications media - transmit
  information through the air.

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LANs, MANs, WANs, and Communications
MediaTelecommunications Media The Paths That
Carry Information

• Wired Communications Media include
• Twisted-pair cable
• Coaxial cable
• Optical Fiber
• Wireless Communications Media Include
• Microwave
• Satellite
• Infrared

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LANs, MANs, WANs, and Communications
MediaBandwidth

• Bandwidth - refers to the amount of information
  that a communications medium can transfer in a
  given amount of time.

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LANs, MANs, WANs, and Communications MediaWired
Communications Media

• The simplest type of twisted-pair phone cabling
  (Cat 1) provides a slow, fairly reliable path for
  information at up to 64 kilobits per second
  (Kbps).
• A better type (Cat 3) provides up to 10 megabits
  per second (Mbps).

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4-Pair Unshielded Twisted Pair Cable with RJ-45
Connector
The cord terminates in an 8-pin RJ-45 connector,
which plugs into an RJ-45 jack in the NIC,
switch Or wall jack. Your home phone has a
6-pin RJ-11 plug. But only two wires Out of the
possible six are Used.
Pin 1 on left of Jack
8-Pin RJ-45 Connector
RJ-45 Jack
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4-Pair Unshielded TwistedPair Cable with RJ-45
Connector
UTP Cord
RJ-45 Connector
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4-Pair Unshielded TwistedPair Cable with RJ-45
Connector
With RJ-45 Connector
Pen
4 Pairs Separated
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LANs, MANs, WANs, and Communications MediaWired
Communications Media

• Optical fiber - uses a very thin glass or plastic
  fiber through which pulses of light travel.

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Optical Fiber Cabling
Two-fiber cords for full-duplex (two-way)
transmission
SC Connectors (Recommended)
ST Connectors (Popular)
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Optical Fiber Cabling
ST Connectors (Push In and Snap)
ST Connectors (Bayonet Push In and Twist)
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LANs, MANs, WANs, and Communications MediaWired
Communications Media

• Coaxial cable (coax) - one central wire
  surrounded by insulation, a metallic shield, and
  a final case of insulating material.
• Coax is the kind of cable that delivers cable
  television transmissions and also carries
  satellite TV from the dish to your house.

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LANs, MANs, WANs, and Communications
MediaWireless Communications Media

• Wireless communications media radiate information
  into the air, either very narrowly beamed or in
  many directions like ripples from a pebble tossed
  into a pond.

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LANs, MANs, WANs, and Communications
MediaInfrared and Omnidirectional Microware for
Short Distances

• Infrared - a wireless communications medium that
  uses radio waves to transmit signals or
  information.
• Microwave transmission - a type of radio
  transmission.
• Bluetooth
• WiFi

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LANs, MANs, WANs, and Communications
MediaDirectional Microware for Medium Distances

• Repeater - a device that receives a radio signal,
  strengthens it and sends it on.

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LANs, MANs, WANs, and Communications
MediaSatellites for Long Distance

• Communications satellites - microwave repeaters
  in space.

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Communications Service Providers

• Communications service providers - third parties
  who furnish the conduit for information.
• Public network - a network on which your
  organization competes for time with others.

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Communications Service Providers

• Private network - communications media that your
  organization owns or exclusively leases to
  connect networks or network components.
• Value-added network (VAN) - a semipublic network
  that provides services beyond the movement of
  information from one place to another.

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Communications Service Providers

• Virtual private network (VPN) uses software to
  establish a secure channel on the Internet for
  transmitting data.

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Communications Service ProvidersKey
Considerations for Communications Media

• To determine the most appropriate communications
  medium, you must consider
• Capacity
• Reliability
• Cost
• Distance
• Mobility