Internet Technologies and Security

Networking Basics

With regard to internet technologies, there are three basic network configurations used to connect businesses and people to the internet.   The network configuration that is used is predominantly determined by the physical location of the network. 

Local Area Networks (LAN) 

A Local Area Network(LAN) provides networking capability to a group of computers in proximity to each other such as in an office building, a school, or a home. A LAN is useful for sharing resources like files, printers, games or other applications.  A LAN is typically used for applications in a small area such as an office building, university, or even a residential home. Most mid to large-sized businesses today use LANs, which make it easy for employees to share information.  LANs are either ethernet-based or wireless.   Computers connected to the LAN are called nodes.  A hub connects multiple nodes on a LAN network.   LANs are designed as peer-to-peer or client/server configurations depending upon the size of the network. 

  Peer-to-peer configurations are typically used for a home or small office whereas a client/server configuration is used in applications where there are multiple devices connecting to the network (PC's, printers) and that network has one or more servers.  

 A client/server LAN uses a network operating system to manage the main functions of the network such as data storage, email services, remote communications for employees out of the office, centralized storage of files, and management of web-based services.  

Metropolitan Area Networks (MAN)

A Metropolitan Area Network(MAN) is a computer network which connects computers in multiple

locations across a city or multiple university, government, or research locations across a region.  The primary difference between a Metropolitan Area Network versus a LAN is that it covers a large area or group of buildings and is not generally owned by a single organization.  The communication links and equipment are generally owned by a consortium of users or by a network service provider that sells the service to the users. 

Wide Area Networks (WAN)

A Wide Area Network (WAN) is long-distance network that covers a wide geographic area, such as a state or country.  WANs service large regional areas or an entire nation. Large enterprises have their own private WANs to link remote offices.  A Wide Area Network can be comprised of multiple connected LANs.  Unlike LANs, WANs are not limited to a single location. Many wide area networks span long distances via telephone lines, fiber-optic cables, or satellite links. They can also be composed of smaller LANs that are interconnected. The Internet could be described as the largest WAN in the world.