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Networking |
Networking refers to connecting a computer to other
computers or network devices. The internet can be thought of as the
world's largest network, consisting of millions of computers and
devices worldwide. Computers can also be part of a private network
with as little as two computers connected to each other. The many
types of networks and network connections vary greatly in cost and
speed.
Dial-up networking is the original widespread method of connecting
home users to the internet. In this method, the computer uses data
signals sent over regular phone lines to communicate with another
computer known as a server. The server has a high-speed connection
to other internet servers, which it uses to fetch data requested by
the dial-up user. This is the slowest type of network connection
widely used today, and is limited to a maximum speed of 56 kilobits
per second.
Broadband, such as DSL (Digital Subscriber Line) and Cable internet,
provide higher-speed connections to the internet. DSL uses the same
phone lines as dial-up internet, but transmits data using much
higher frequency signals. Because of this, it can send data more
quickly and does not interfere with normal phone usage. Cable
internet uses the same principle as DSL, except it uses Cable TV as
its connection medium. Broadband speeds are commonly available from
256 kilobits per second to 7 megabits per second. Both DSL and Cable
require special modems to connect to the network, and are then
connected to the computer (or other device, such as a router) by
either an Ethernet or USB cable.
Ethernet is the most common type of networking used in private
networks, such as when connecting multiple computers together within
a home. Two computers can be directly connected using a special
Ethernet cable called a crossover cable. In such a configuration,
the computers can directly transfer data to each other very quickly,
nearly at the full 100 megabits (or 12.5 megabytes) per second.
Connecting devices directly like this is, however, limited to two
devices. To connect more devices together, a router is used.
The router (such as the popular Linksys WRT-54G) allows multiple
devices to connect to it with a regular Ethernet patch cable. Most
routers also provide a “WAN” (Wide Area Network) or “Modem” port,
used to connect the private network to another network such as the
internet. In this configuration, each device can transfer data to
any other device on the private network. If multiple devices are
transferring data at the same time, the actual transfer rate might
be significantly slower than 100 megabits per second. If connected
to another network via the WAN port, the computers on the private
network can also transfer data to any computer available on the Wide
Area Network. |
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