Videoconferencing is a set of interactive telecommunication technologies, which allow two or more locations to interact via two-way video and audio transmissions simultaneously. It differs from videophone in that it is designed to serve a conference rather than individuals. Besides the audio and visual transmission of meeting activities, videoconferencing can be used to share documents, computer-displayed information, and white boards. There are cheap and convenient uses of videoconferencing such as Net Meeting, MSN Messenger, Yahoo Messenger, and Skype.
Bluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range based on low-cost transceiver microchips in each device to communicate with each other when they are in range. Since the devices use a radio broadcast communications system, they do not have the be in line of sight of each other.
Applications of Bluetooth
- Wireless control of and communication between a mobile phone and a hands-free headset. This was one of the earliest applications to become popular.
- Wireless networking between PCs in a confined space and where little bandwidth is required.
- Wireless communication with PC input and output devices, the most common being the mouse, keyboard, and printer.
- Transfer of files, contact, details, calendar appointments, and reminders between devices with OPEX.
- Replacement of traditional wired serial communications in test equipment, GPS receivers, medical equipment, bar code scanners, and traffic control devices.
- For controls where infrared was traditionally used
- Sending small advertisements from Bluetooth-enabled advertising hoardings to other discoverable Bluetooth devices.
- Nintendo Wii and Sony Playstation 3 use Bluetooth in their wireless game controllers.
- Dial-up Internet access on personal computers or PDAs using a data-capable mobile phone as a modem.
WiFi is a trademark of the Wi-Fi Alliance, founded in 1999. It comprises more than 300 companies, whose products are certified by the Wi-Fi Alliance, based on certain standards identified as IEEE 802.11 (also known as WLAN). This certification warrants interoperability between different wireless devices. IEEE 802.11 is a set of standards carrying out wireless local area network (WLAN) computer communication in the 2.4, 3.6, and 5 GHz frequency bands.
The Wi-Fi Alliance tests the wireless components to their own terms of reference. Products that pass become Wi-Fi certified and may carry the Wi-Fi logo. Only products of Wi-Fi are tested because they pay membership and per-item feeds. Absence of the Wi-Fi logo does not necessarily mean non-compliance with the standard. Wi-Fi certification is provided for technology used in home netwoeks, mobile phones, video games, and other devices that require wireless networking. Most personal computer operating systems, many game consoles, laptops, smartphones, printers, and other peripherals support Wi-Fi.
A Wi-Fi enabled device such as a PC, game console, mobile phone, MP3 player of PDA can connect to the Internet when within range of a wireless network connected to the Internet. The coverage of one or more interconnected access points, a hot spot, can comprise an area as small as a single room with wireless-opaque walls or as large as many square miles covered by overlapping access points.
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