Network Scale :
We classify Multiple processor system based on physical size and is Illustrated.
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Classifications of Processors by scale
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Personal Area Network:
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Personal Area Network
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At the top we have personal area networks(PAN), This networks meant for a single person. For Example a wireless network connecting a computer with its mouse, keyboard and a printer can constitute a personal area network.
Local Area Network :
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Local Area Network
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Local area networks are generally called LANs. They are privately owned networks within a single building or campus of up to few kilometers in size. Most of the LAN's use Bus or ring topology for connection. They are used to connect personal computers and workstations in company offices and factories to share resources and exchange information. Traditional LANs run at speeds of 10Mbps to 100mbps, have low delay (microseconds and nanoseconds)and make veryfew errors. Newer LANs operate at 10Gbps. Various topologies are possible for broadcast LANs.
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Metropolitan Area Network
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Metropolitan Area Networks :
A metropolitan Area Networks, referred as MANs covers a city. The best Know Example is cable television network available in many cities. Earlier these were used for TV reception only but with changes a two way internet service could be provided. In this system both television signals and internet being fed into centralized head end for distribution to people's home.
Cable television is not the only MAN. Recent developments in high speed wireless internet access also resulted in MAN.
Wide Are Network:
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Wide Area Network
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A wide area network is referred as WAN. WAN spans a large geographical area often a continent or country. WAN contains a collection of machines, traditionally called as hosts.These hosts can be on LANs and are connected by a subnet or also called communication subnet. The hosts are owned by customers or area personal computers. The communication subnets area owned by a telephone company or internet service provider. The subnet carries the messages from hosts to hosts, just as telephone system carries words from speaker to listener. Each host is connected to a LAN on which a router is present. Sometimes a host may be connected directly to a router. The collection of communication lines and routers is called a communication subnet. In most WANs, the network contains many transmission lines each connecting a pair of routers. A packet is sent from one router to another via one or more intermediate routers.The packet is received at each intermediate router in its entirety. That is store the packet in full until the required output line is free, and then forwards it. A subnet that works according to this principle is called store and froward or packet switched subnet. Not all WAN,s are packet switched. A second possibility for a WAN is a satellite system. Satellite networks are inherently broadcast networks.
Wireless Networks :
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Wireless Network
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The Italian physicist Guglielmo Marconi in 1901. Demonstrated a ship-to-shore telegraph, using Morse code is a collection of binary digits called dots and dashes. Modern digital wireless systems have better performance, but the basic idea is the same. Wireless networks are divided into three main categories.
- System interconnection.
- Wireless LANs.
- Wireless WANs.
System interconnection:
It is all about interconnecting the components of a computer using short range radio. Every computer has a monitor, keyboard, mouse, printer connected to the main unit by cables.
Wireless LANs:
These are systems in which every computer has a radio modern and a antenna with which it can communicate with other systems. Often there is an antenna on the ceiling that the machines talk. Wireless LANs are becoming common in small offices and homes, where installing Ethernet is considered too much trouble. Also used in older buildings, company cafeteriasa, conference rooms etc. Standard for wireless LANs IEEE 802.11.
Wireless WANs:
These are wide area system which contains wireless routers. Sending signals to satellite and received signals from it.
