The Digital Living network Alliance (DLNA) is a group of companies working to create a common, open standard for connecting devices.
DLNA compatible devices include TVs, mobile phones, PCs and laptops, music players, consoles such as the PLAYSTATION®3, printers and Hifi systems.
DLNA devices have been designed to connect to one another. Each device is classed according to its use. For example, any device which stores content is classed as a Digital Media Server (such as a mobile phone storing photos, music and video in its memory). And any device which can play digital content from another DLNA device is known as Digital Media Player (such as your BRAVIATM TV which can show and play photos, videos and music from other devices).
DLNA certified devices connect and communicate with each other over a home network. This works using similar set-up you may have for your Internet connection. In fact, a router is the key communication point of the network as it is used to link devices to each other.
You must connect DLNA certified devices to your Home Network to play back on your Sony Tablet contents stored on another device (Media server) or play back on other device (Media player) the contents stored on your Sony Tablet.