The true power of Digital Signage is realized when the media players controlling the content displayed is connected to a distribution system. The distribution system enables the administrator to quickly and easily control the content displayed from a central location.
In order to achieve a connected network of display units, each media player needs to be connected to a network. There are two ways to achieve this: Video Distribution or using the Internet Protocol (IP).
Video distribution is a form of connecting display units together using video distribution equipment. These are hardware that propagate an audio video signal to multiple display units by using audio video splitters, cables, boosters and other A/V equipment.
This is an older method for building a Digital Signage network that is still used in smaller deployments. The main advantage of this type of a network is that it can result in a limited but really easy to use solution. The source device is often a DVD player, satellite, cable, or some other video signal. Due to this reason the administrator can control the content with a standard remote control and the distribution system takes care of carrying the video signal to all the screens. The disadvantage is that it is extremely limited in features and flexibility. The display units and distribution is fixed and often can only display a single video signal, and scheduling features are very basic.
The distribution of audio video content using the Internet Protocol is a newer form of building a Digital Signage network. Each media player is connected to a Digital Signage server over the IP network. The IP network can be connected to the Internet to create a network of display units that span the globe with tens of thousands of display units.
The Digital Signage server converts audio video and other digital media content to a form that can be sent over the IP network and sends it to the correct media player according to how the administrator has configured the system. The media player then receives this content and converts to an audio video signal that can be displayed on the screen.
The advantage of IP based Digital Signage is that it allows the administrator to do much more with the network with great flexibility. The scheduling and distribution can be reconfigured at any time making it far more powerful than the video distribution network.
The disadvantage is that the administrator requires some computer skills to operate the administration console. The Digital Signage software packages have come a long way in the past few years resulting in simple to use systems.
There are some networks that can use a hybrid of both IP and AV distribution. In these networks, the IP network is used to transmit the digital content to a media player at a location, then this media player is connected to an audio video distribution network to propagate the signage to the screens. This removes the need for a media player attached to each screen resulting in a network that is, in some cases, lower cost at the expense of loss of some flexibility. That is, all screens at the location will be fed from a single media player which means they will all display the same content.
With new low cost media players, there is little to no cost savings from hybrid systems. In fact many media players cost less than the AV hardware therefore it is better to use the pure IP network when using a Digital Signage system.