Foundations of Information Technology

1.05a

Local Area Networks (LANs)◦Small networks in a limited geographical area

Wide-Area Networks (WANs)◦Extensive networks that may span hundreds of miles

Public Access Networks (PANs) Value Added Networks (VANs) Virtual Private Networks (VPNs) Metropolitan Area Network (MAN)

Networks Classified by Coverage

Private networks, for businesses, organizations or schools, with computers located in the same building or area.

Provides convenience for multiple users to share programs, data, information, hardware, software and other computing resources.

Uses a special computer called a file server to house all network resources

Allows users to access programs and data from the file server.

The print server allows multiple users to share the same printer.

Using networks saves companies money in hardware, software, and related costs.

Local Area Networks (LANs)

Local Topologies

Wide-Area Networks (WANs) Span large geographical

areas connecting two or more LANs.

Use to share data between separate networks by Government, Universities, & large Corporations.

Typically make use of high-speed leased telephone lines, wireless satellite, or both.

Wide-Area networks operated and maintained by a large company.

Provides voice and data communication for a fee.

Public Access Networks (PANs)

Value Added Networks (VANs) - Business that use facilities of large communication companies to provide subscribers with additional services.

Virtual Private Networks (VPNs) – a cost effective way to expand network use

Metropolitan Area Network (MAN) – a wide area network limited to specific site, such as a city or town.

Other Networks

The layout or pattern by which the network is organized.

Common topologies◦Bus◦Star◦Ring

Network Topologies

A sing line of cable with two endpoints links all computers.

All communications travel the full length of the bus

Each computer network transceiver checks the message for its intended destination

Bus Topology

Multiple computers and peripheral devices are linked to a central computer called a host.

The host computer is generally a more powerful midrange or mainframe computer.

Star Topology

There is NO Host Computer Each computer is connected to two other

computers in a circular path.

Ring Topology

Networked personal computers, workstations, or terminals (clients) can send request to, and receive services from, a more powerful computer (a server).

Client/Server Network

Computers that comprise the network have equivalent capabilities and responsibilities.

Each computer acts as both client and server.

Peer-to-Peer Network