Networks What are they and how do they work?

What is a Network?  Hardware and software data communication system  Two or more devices connected for the purpose of sharing data or services

What does a Network Do?  Access Data  Share hardware and software  Share files  Save personal files in a secure centralized location A Network allows users to:

How are networks classified?  Peer to Peer – Two or more computers in the same proximity connected to each other

How are networks classified?  LAN (Local Area Network) – A data communications network which is geographically limited, such as your entire campus.

How are networks classified?  WAN (Wide Area Network) - A network extending over distances greater than one kilometer, such as all of the Cedar Hill Independent School District, a large corporation, or even the WWW.

Types of Networks Continued…  The “ultimate” WAN  Available worldwide (World Wide Web)  Worldwide collection of networks that links together millions of commercial (.com), education (.edu), non profit (.org), public networks (.net), government (.gov), military (.mil) as well as individual sites Internet

What components are required?  Before network components can communicate they must be connected  A Network Adapter – a circuit board installed in a computer or network device to provide a physical connection to a network

NIC – Ethernet Card  NIC (Network Interface Card) – typically an Ethernet card such as those installed in the Middle School Computer Applications labs  The cable which attaches to this type of card has 8 smaller twisted wires

Types of Networks Continued…  A private network  May be protected by a “firewall”  May require a User ID and password  May be available worldwide but not open to the general public Intranet

Hubs, Switches, Routers  Multi-port hardware components that allow several components to be attached to a single port or connection Hub Switch Router

Wireless Card  WI-FI – (Wireless Fidelity) The standard for manufacturer of wireless network components. Such adaptors may be built into desktops or inserted into notebooks  No cables required, only an access point

Communication Software  All network components require software  Different networks components communicate with different types of software: Drivers Drivers Network Operating System Network Operating System Network Client Network Client Browsers Browsers

Drivers  Drivers are the software packages that control hardware components  All adaptors must have drivers loaded in order to communicate  Some drivers load automatically utilizing the operating system  Some drivers must be installed from floppy disks or CDs

Network Operating Systems  Networks that connect to a common server or servers require a Network Operating System (NOS)  A NOS allows resources such as file storage, application programs, and printers to be shared  A NOS may allow users to save their files in a secure environment

Network Operating Systems  Common Network Systems include: Unix Unix Novell Novell Microsoft NT Microsoft NT LANtastic LANtastic MS LAN Manager MS LAN Manager

Internet Access Software  ISP (Internet Service Provider) – Access to the Internet is provided by companies licensed to provide such services AOL AOL Internet America Internet America SBC, Verizon, AT&T, Sprint SBC, Verizon, AT&T, Sprint  They provide specific access software, User ID, password, and possibly and web space

Network Clients  All computers that access a Network Operating System must have a client

Browsers  All computers that access the Internet or Intranet must have a browser  Browsers include Internet Explorer Internet Explorer Netscape Netscape Opera Opera Mozilla Mozilla UltraBrowser UltraBrowser

Shared Components  Server – A computer which provides services for users of other computers connected within a network, LAN or WAN. Authentication of users Authentication of users Read/write shared and personal files Read/write shared and personal files Print services Print services  Printer – Registered network users may access common printers reducing the number of required printers

Additional Hardware  Cable – individual components in a network are connect from one adaptor or component to the next with cables Fiber optic Coaxial Ethernet or Telephone

Identify The Following  Network adaptor or NIC  Ethernet cable  Hub, switch, or router  Server  Network printer How many of the following can you identify in your classroom?

Identify The Following  Network Operating System (NOS)  Network Client  Browser  Drivers  ISP software Identify software provided in your classroom for each of the following categories?

Compare and Contrast  LAN and WAN Similarities Similarities Differences Differences

Compare and Contrast  Internet and Intranet Similarities Similarities Differences Differences

Networks