18-08-2012, 04:02 PM
NETWORKING FUNDAMENTALS
NETWORKING FUNDAMENTALS.pptx (Size: 362.82 KB / Downloads: 22)
WHAT IS A NETWORK?
A network is simply two or more computers that are linked together.
The most common types of networks are:
Local Area Networks (LANS) and
Wide Area Networks (WANS).
The primary difference between the two is that a LAN is generally confined to a limited geographical area, whereas a WAN covers a large geographical area. Most WANs are made up of several connected LANs.
TYPES OF NETWORKS
Intranet – An intranet is a private LAN designed for use by everyone within an organization. An intranet might consist of an internal e-mail system, a message board and one or more Web site portals that contain company news, forms, and personnel information.
Access to an intranet’s web site is restricted by a firewall.
Extranet – a network that connects people within your company with people who are outside your company--all within a secure, password-protected network that can be accessed from anywhere.
anywhere.
BENEFITS OF A NETWORK
Information sharing: Authorized users can use other computers on the network to access and share information and data. This could include special group projects, databases, etc.
Hardware sharing: One device connected to a network, such as a printer or scanner, can be shared by many users.
Software sharing: Instead of purchasing and installing a software program on each computer, it can be installed on the server. All of the users can then access the program from a single location.
Collaborative environment: Users can work together on group projects by combining the power and capabilities of diverse equipment.
WIRELESS MEDIA
Microwave system – transmits data via high-frequency radio signals through the atmosphere
Satellite system – receive transmitted signals, amplify them, and then transmit the signals to the appropriate locations
Cellular technology – uses antennae resembling telephone towers to pick up radio signals within a specific area (cell)
Infrared technology – transmits data as infrared light waves from one device to another, providing wireless links between PCs and peripherals
Note: The type selected is determined by the type ofnetwork, the size of the network, and the cost.
EXAMPLE OF AN ETHERNET BUS
Ethernet LANs use a bus topology.
All stations are connected to a single long cable.
Any station can send a signal along the cable, which all other stations will receive. Unlike ring topologies, the cable doesn't close a loop.