week 5

what is networking ?

A network consists of two or more computers that are linked in order to share resources (such as printers and CDs), exchange files, or allow electronic communications. The computers on a network may be linked through cables, telephone lines, radio waves, satellites, or infrared light beams. 

Two very common types of networks include;

·         local Area Network (LAN) 

           Wide Area Network (WAN)

You may also see references to a Metropolitan Area Networks (MAN), a Wireless LAN (WLAN), or a Wireless WAN (WWAN).

 Local Area Network

A Local Area Network (LAN) is a network that is confined to a relatively small area. It is generally limited to a geographic area such as a writing lab, school, or building. Computers connected to a network are broadly categorized as servers or workstations.

Workstations are called such because they typically do have a human user which interacts with the network through them. Workstations were traditionally considered a desktop, consisting of a computer, keyboard, display, and mouse, or a laptop, with integrated keyboard, display, and touchpad. With the advent of the tablet computer, and the touch screen devices such as iPad and iPhone, our definition of workstation is quickly evolving to include those devices, because of their ability to interact with the network and utilize network services. 

Wide Area Network

Wide Area Networks (WANs) connect networks in larger geographic areas, such as Florida, the United States, or the world. Dedicated transoceanic cabling or satellite uplinks may be used to connect this type of global network.

sing a WAN, schools in Florida can communicate with places like Tokyo in a matter of seconds, without paying enormous phone bills. Two users a half-world apart with workstations equipped with microphones and a webcams might teleconference in real time. A WAN is complicated. It uses multiplexers, bridges, and routers to connect local and metropolitan networks to global communications networks like the Internet. To users, however, a WAN will not appear to be much different than a LAN.

Metropolitan area network

A metropolitan  area network (MAN) is a computer network that usually spans a city or a large campus. A MAN usually inter connects a number of local area network (LAN) using a high-capacity backbone technology, such as fiber-optical links,and provides up-link services to wide area network(or WAN) and the internet.

Personal area network

 A personal area network (PAN) is a computer network used for communication  among computerized devices, including telephones  and personal digital assistans. PANs can be used for communication among the personal devices themselves (intrapersonal communication), or for connecting to a higher level network and the internet(an uplink). 
A wireless personal area network (WPAN) is a PAN carried over wireless network technologies such as irDA, Bluetooth,Wireless USB, zigBee, or even Body carried over wired computer buses such as USB and FireWire.
A wireless personal area network (WPAN) is a personal area network - a network for interconnecting devices centered around an individual person's workspace - in which the connections are wireless. Wireless PAN is based on the standard IEEE 802.15. The three kinds of wireless technologies used for WPAN are Bluetooth,infrared data Association, and Wi-Fi.

Bluetooth

Bluetooth uses short-range radio waves over distances up to approximately 10 metres. For example, Bluetooth devices such as a keyboards, pointing devices, audio head sets, printers may connect to personal digital assistants (PDAs), cell phones,or computers wirelessly.

A Bluetooth PAN is also called a piconet(combination of the prefix "pico," meaning very small or one trillionth, and network), and is composed of up to 8 active devices in a master-slave relationship (a very large number of devices can be connected in "parked" mode). The first Bluetooth device in the piconet is the master, and all other devices are slaves that communicate with the master. A piconet typically has a range of 10 metres (33 ft), although ranges of up to 100 metres (330 ft) can be reached under ideal circumstances.