A wireless
network enables people to communicate and access applications and
information without wires. This provides freedom of movement and the ability to
extend applications to different parts of a building, city, or nearly anywhere
in the world. Wireless networks allow people to interact with e-mail or browse
the Internet from a location that they prefer.
Many types
of wireless communication systems exist, but a distinguishing attribute of a
wireless network is that communication takes place between computer devices.
These devices include personal digital assistants (PDAs), laptops, personal
computers (PCs), servers, and printers. Computer devices have processors,
memory, and a means of interfacing with a particular type of network.
Traditional cell phones don't fall within the definition of a computer device;
however, newer phones and even audio headsets are beginning to incorporate
computing power and network adapters. Eventually, most electronics will offer
wireless network connections.
As with
networks based on wire, or optical fiber, wireless networks convey information
between computer devices. The information can take the form of e-mail messages,
web pages, database records, streaming video or voice. In most cases, wireless
networks transfer data, such as e-mail messages and files, but advancements in
the performance of wireless networks is enabling support for video and voice
communications as well.
Types of Wireless Networks
WLANS: Wireless Local Area Networks
WLANS allow
users in a local area, such as a university campus or library, to form a
network or gain access to the internet. A temporary network can be formed by a
small number of users without the need of an access point; given that they do
not need access to network resources.
WPANS: Wireless Personal Area Networks
The two
current technologies for wireless personal area networks are Infra Red (IR) and
Bluetooth (IEEE 802.15). These will allow the connectivity of personal devices
within an area of about 30 feet. However, IR requires a direct line of site and
the range is less.
WMANS: Wireless Metropolitan Area Networks
This
technology allows the connection of multiple networks in a metropolitan area
such as different buildings in a city, which can be an alternative or backup to
laying copper or fiber cabling.
WWANS: Wireless Wide Area Networks
These types
of networks can be maintained over large areas, such as cities or countries,
via multiple satellite systems or antenna sites looked after by an ISP. These
types of systems are referred to as 2G (2nd Generation) systems.
Comparison of Wireless Network Types
Type
|
Coverage
|
Performance
|
Standards
|
Applications
|
Wireless PAN
|
Within reach of a person
|
Moderate
|
Wireless PAN Within reach of a
person Moderate Bluetooth, IEEE 802.15, and IrDa Cable replacement for
peripherals
|
Cable replacement for peripherals
|
Wireless LAN
|
Within a building or campus
|
High
|
IEEE 802.11, Wi-Fi, and HiperLAN
|
Mobile extension of wired networks
|
Wireless MAN
|
Within a city
|
High
|
Proprietary, IEEE 802.16, and
WIMAX
|
Fixed wireless between homes and businesses
and the Internet
|
Wireless WAN
|
Worldwide
|
Low
|
CDPD and Cellular 2G, 2.5G, and 3G
|
Mobile access to the Internet from
outdoor areas
|
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