Discuss current and forthcoming developments in short-range wireless standards.

What will be an ideal response?

There are several wireless networking standards in existence or being developed that are designed for short-range wireless networking connections (for a summary of these standards and the standards already discussed, see Figure 8-19). Bluetooth is a wireless standard
that was originally designed for very short-range (10 meters, approximately 33 feet, or less) connections, though there is no maximum range and some industrial products have a range of 300 feet. Bluetooth is designed to replace cables between devices, such as to connect a wireless keyboard or mouse to a desktop computer, to send print jobs wirelessly from a portable computer to a printer, or to connect a mobile phone to a wireless headset. The Bluetooth standard is continually evolving to be faster and to support new applications.
One of the key enhancements in the newest Bluetooth specification (Bluetooth 4.0, also called Bluetooth Smart) is low energy, which enables small devices to run for years on a single button-sized battery. Consequently, Bluetooth is increasingly being used with consumer devices, such as to connect health and fitness devices to a watch or smartphone, to connect a mobile phone to a portable speaker, and to connect 3D glasses to a 3D television set.
         Another standard that is designed to connect peripheral devices, similar to Bluetooth, but that transfers data more quickly is wireless USB. The speed of wireless USB depends on the distance between the devices being used, but it is approximately 100 Mbps at 10 meters (about 33 feet) or 480 Mbps at 3 meters (about 10 feet). While Bluetooth and wireless USB can be used for similar applications, it is possible they might coexist. For example, wireless USB might be used to connect computer hardware in more permanent setups, while Bluetooth might be used in short-range mobile situations with portable computers and mobile devices.
         A newer standard also designed to connect devices for short-range communications is Wi-Fi Direct. Wi-Fi Direct enables Wi-Fi devices to connect directly to each other, such as to transfer photos or documents or to tether devices to a Wi-Fi Direct device’s Internet connection by creating a hotspot (see Figure 8-20), without needing any additional networking hardware. Wi-Fi Direct is not designed to replace traditional Wi-Fi networks, but it is considered a competitor to Bluetooth because it has the advantage of faster speeds (up to 250 Mbps) and a greater range (up to 600 feet).
         For transferring multimedia content quickly between nearby devices (such as between televisions and DVD players, or between computers and mobile devices), a number of different standards are emerging. For instance, Ultra Wideband (UWB) transfers data at speeds from 100 Mbps at 10 meters (about 33 feet) to 480 Mbps at 2 meters (about 6.5 feet). Similar, but faster, standards include WiGig, which is being developed by the Wi-Fi Alliance and supports short-range data transfers of up to 7 Gbps, and wirelessHD (WiHD), which is backed by seven major electronics companies and is designed to transfer full-quality uncompressed high-definition audio, video, and data within a single room at speeds up to 28 Gbps. A wireless standard designed for fast transfers between devices that are extremely close together (essentially touching each other) is TransferJet. Developed by Sony, TransferJet is designed to transfer large files (such as
digital photos, music, and video) quickly between devices as soon as they come in contact with each other (such as to transfer data between smartphones or between digital cameras, to download music or video from a consumer kiosk or digital signage system to a smartphone or other mobile device, or to transfer images or video from a digital camera to a TV or printer). At a maximum speed of 560 Mbps, TransferJet is slower than some of the other technologies, but it is fast enough to support the transfer of video files.