BLUETOOTH:

           The simplest and most common way for two hand held devices to communicate with each other is via Bluetooth. Bluetooth networking transmits data via low-power radio waves. It communicates on a frequency between 2.402 GHz and 2.480 GHz. This frequency band has been set aside by international agreement for the use of industrial, scientific and medical devices (ISM). Bluetooth devices send out weak signals of about 1 mill watt to avoid interference with other devices such as computers and cell phones. This low power, however, limits its range to 10 meters, but its signal can pass through walls so direct line of sight is not required.

           Another great advantage of Bluetooth is that it can connect up to eight devices simultaneously without interference. It use a technique called “spread-spectrum frequency hopping” which, put in simple words, means it keeps changing its frequency in the designated range and thus interference, if any, lasts for a fraction of a second and goes unnoticed.

            Like any wireless network, security is a concern with Bluetooth. The automatic nature of the connection which makes it easy to use can also be used against you by sending data without your permission. To avoid this, Bluetooth offers several security modes, and device manufacturers determine which mode to include in a Bluetooth-enabled gadget, the user has to decide whether to allow it. If you use the device quite often, you can mark the device as trusted and it will be able to exchange data without permission.

CEC (CONSUMER ELECTRONIC CONTROL):

          One of the biggest challenges of technological revolution is creating intelligent devices that can communicate with each other. The CEC technology brings us one step closer to the dream. CE (CONSUMER ELECTRONIC) devices can automatically configure themselves and correct errors without user intervention. Using the HDMI frame work, CEC takes user experience to a whole new level. For example, you can connect your camcorder to your CEC-enabled HDTV and TV will automatically detect the device and display it on the screen. You can control your camcorder with your CEC-enabled HDTV. Same goes for DVD players and set-top boxes; you don’t need to switch remotes when you use different devices. Unlike DLNA, interportability is an issue here. You can control devices only of they have the same manufacturer.

DLNA (DIGITAL LIVING NETWORK ALLIANCE):

When people started networking home entertainment devices, it was difficult and confusing to add a new device and get it to communicate with their computers and other network devices. There was need for standards and guidelines for home networking media devices. So, several manufactures got together to create a standard so that all of their products were compatible in a home network and thus the digital living network alliance was born in 2003. When a device is DLNA certified devices irrespective of the manufacturer of the product. DLNA certified devices can: find and play movies; send, display and/or upload photos; find, send, play and/or download music; and send and print photos. DLNA uses universal plug and play (UPnP) for media management, discovery and control so they require little or no setup and can be immediately connected to your existing DLNA network.