Types of Proximity Based Wireless Reach

Just as cable-based network, the wireless network can be classified into several distinct types based on the distance where the data can be transmitted.



1. Wireless Wide Area Networks (WWAN)


WWAN technology enables users to establish wireless connections over a public network and private. This connection can be made covers a very broad area, such as cities or countries, 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 features global roaming as well. ITU is also active in promoting the creation of global standards for 3G technology.


2. Wireless Metropolitan Area Networks (WMAN)


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



3. Wireless Local Area Networks (WLAN)


WLAN technology allows users to build a wireless network in an area of ​​local nature (for example, in the office building environment, building on the campus or public areas, like airports or cafes). WLAN can be used in temporary offices or in which the permanent cable installation is not allowed. Or WLAN sometimes built as a supplement to an existing LAN, so users can work at different locations within the building. WLAN can be operated in two ways. In the WLAN infrastructure, wireless stations (devices with radio network cards or external modem) to connect to a wireless access point that serves as a bridge between the stations and the existing backbone network at the 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 network resources.


In 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 the 802.11b, which became the dominant new standard at this time, the data is transferred at a maximum speed of 11 Mbps through 2.4 gigahertz (GHz). Another newer standard is 802.11a, which specifies data transfers at a maximum speed of 54 Mbps through a frequency of 5 GHz.


4. Wireless Personal Area Networks (WPAN)


WPAN technology enables users to build a wireless network (ad hoc) for simple devices such as PDAs, cell phones or laptops. It can be used in the operating room personnel (personal operating space or POS). A POS is a space which is around people, and can reach a distance of about 10 meters. Currently, 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 within very close distance (1 meter or less), then the user can use infrared light.

To standardize the development of technology WPAN, IEEE 802.15 working group has been building for WPAN. The working group made 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.