DLNA

The Digital Living Network Alliance is a trade-association, which was established by Sony in 2003. Latest survey shows that As of 2011, over 250 companies are part of this organization and As of February 2013, over 18,000 different device models have obtained "DLNA Certified"  it confirms their interoperability with other devices. The basic idea behind the DLNA association is to develop standards and technologies that make it possible that several devices at home interact. An example might be a television, that can be used to play a film on a computer, or to show photos stored on a mobile phone.

DLNA uses Universal Plug and Play (UPnP) for media management, discovery and control.  UPnP defines the type of device that DLNA supports and the mechanisms for accessing media over a network.

Different Home network devices, Mobile handset devices, Home infrastructure devices have DLNA certificates. DLNA Certified devices have been tested to ensure that they'll play nicely with other DLNA devices. set-top box is an example of DLNAPV(Digital Living Network Alliance Premium Video) device, and it could then stream copy-protected content such as movies or TV programmes to your other non-DLNAPV devices


reference: 

http://en.wikipedia.org/wiki/Digital_Living_Network_Alliance

http://www.dlna.org/