Wireless

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Introduction

See also Social media landscape and Wireless use at BMB Library

Wireless access to communication networks is literally 'without wires', a means of communicating that uses low-powered radio waves to transmit data between devices. It also refers to communication without cables or chords where radio frequencies and infrared waves send information along a conduit. Common uses include the various communications defined by the IrDA, the wireless networking of computers and cellular mobile phones.

Wi-Fi

Wireless internet is often referred to as a wi-fi network which also suggests a shortening of the notion of "wireless-fidelity." Curiously, wi-fi is meant to be a play on the phrase hi-fi and is not meant to be an abbreviation for anything (see references). A Wi-Fi setup contains one or more access points (APs) and one or more clients. An AP broadcasts its SSID (Service Set Identifier, "Network name") via packets that are called beacons, which are broadcast every 100 metres. Based on the settings (e.g. the SSID), the client may decide whether to connect to an AP. Also the firmware running on the client Wi-Fi card is of influence. Say two APs of the same SSID are in range of the client, the firmware may decide based on signal strength to which of the two APs it will connect. The Wi-Fi standard leaves connection criteria and roaming totally open to the client. This is a strength of Wi-Fi, but also means that one wireless adapter may perform substantially better than the other. Since Wi-Fi transmits in the air, it has the same properties as a non-switched ethernet network.

Evidence-based information to the wireless handheld

Health concerns

Because wireless uses microwaves similar to those in mobiles, many health concerns are similar. However, the transmission power of a typical wireless access point is less than 100 mW (milliwatt). In comparison, radio waves emitted by a GSM handset can have a power of up to 2 watts, and is typically used at a much shorter distance from the body.