Wireless network

Wireless network technology is actually stretched from voice communication to data networks, which allow users to establish a wireless connection at a certain distance. These include infrared technology, radio frequency and so forth. Devices are commonly used for wireless network includes computers, handheld computers, PDAs, cell phones, tablet PCs and so forth. This wireless technology has so many uses. For example, mobile users can use their cell phones to access e-mail. Meanwhile, the traveler with a laptop can connect to the internet when they are at airports, cafes, trains and other public places. At home, users can connect to their desktop (via bluetooth) to synchronize with his PDA.

To reduce costs, ensure interoperability and promote the widespread adoption of wireless technology, then organizations like the Institute of Electrical and Electronics Engineers (IEEE), Internet Engineering Task Force (IETF),

the Wireless Ethernet Compatibility Alliance (WECA) and the International Telecommunication Union (ITU ) has participated in various standardization efforts. For example, IEEE working group has defined how the information is transferred from one device to another device (using a radio frequency or infrared, for example) and how and when a transmission medium should be used for communication purposes. When building standards for wireless networks, organizations such as IEEE has also overcome the problem of power management, bandwidth, security and a variety of unique problems that exist in the world of wireless networks.

Wireless Wide Area Networks (WWANs)

WWAN technology enables users to establish wireless connections over a public network and private. These connections can be made covering a vast area, such as city or country, through the use of multiple antennas or satellite systems are also held by telecommunications service providers. WWAN technology now known system with 2G (second generation). The core of these 2G systems include Global System for Mobile Communications (GSM), Cellular Digital Packet Data (CDPD) and Code Division Multiple Access (CDMA). Various efforts are underway to transition from 2G to 3G (third generation) who will soon become a global standard and has global roaming feature also. ITU is also an active part in promoting the creation of global standards for 3G technology.

Wireless Metropolitan Area Networks (WMANs)

WMAN technologies enable users to make wireless connections between multiple locations within a metropolitan area (for example, between the different buildings in a city or on a university campus), and this could be achieved without the cost of fiber optic or copper cables that are sometimes very expensive. In addition, WMAN can act as a backup for cable-based networks and he will be active when the cable-based network that was experiencing problems. WMAN using radio waves or infrared light to transmit data. Broadband wireless access networks, which provide users with high-speed access, it is much in demand today. Although there are several different technologies, such as multichannel multipoint distribution service (MMDS) and local multipoint distribution services (LMDS) in use today, but the working group IEEE 802.16 standard for broadband wireless access continues to make the specifications for these technologies.

Wireless Local Area Networks (WLANs)

WLAN technology allows users to build a wireless network in an area of ​​local nature (for example, within the office building, campus buildings or on public areas, such as airports or cafes). WLAN can be used on a temporary office or where the installation of permanent wiring is not allowed. Or WLAN is sometimes constructed as a supplement to an existing LAN, so users can work on a variety of different locations within the building. WLAN can be operated in two ways. In infrastructure WLANs, wireless stations (devices with radio network cards or external modems) connected to a wireless access point that serves as a bridge between the stations and the network backbone available at that time. In WLAN environments that are peer-to-peer (ad hoc), some users in limited areas, such as meeting rooms, can form a temporary network without using an access point, if they do not require access to resources jaringan.Pada 1997, to approve the IEEE 802.11 standard for WLANs, which specifies a data transfer rate of 1 to 2 megabits per second (Mbps). Under 802.11b, which became the dominant new standard at this time, data is transferred at a maximum speed of 11 Mbps over a frequency of 2.4 gigahertz (GHz). Other newer standard is 802.11a, which specifies a maximum data transfer at speeds of 54 Mbps through a frequency of 5 GHz.

Wireless Personal Area Networks (WPANs)

WPAN technologies allow users to build a wireless network (ad hoc) for simple devices such as PDAs, cell phones or laptops. It could be used in the operating room personnel (personal operating space or POS). A POS is a space that exist around people, and can reach a distance of about 10 meters. At present, two key WPAN technologies are Bluetooth and infrared light. Bluetooth is a cable replacement technology that uses radio waves to transmit data up to a distance of about 30 feet. Bluetooth Data can be transmitted through walls, pocket or purse. Bluetooth technology is driven by a body called the Bluetooth Special Interest Group (SIG), which publishes the Bluetooth specification version 1.0 in 1999. Another alternative way to connect devices in very close proximity (1 meter or less), then the user can use infrared light merah.Untuk standardize the development of WPAN technologies, IEEE 802.15 working group has been building for WPAN. The working group makes WPAN standard, based on the Bluetooth specification version 1.0. The main objective of this standardization is to reduce complexity, lower power consumption, interoperability, and can coexist with 802.11 networks.