A consortium of the world's largest computer and electronics companies met this week to establish ground rules for building compatible electronic devices for sharing movies and music.

RealNetworks was absent from the proceedings, but told Reuters it would consider joining at a later date. Apple, also absent from the event, was not immediately available for comment.

Products will need to meet the specifications set by the Digital Living Network Alliance in order to qualify for a logo that will let shoppers know if a device will work with other certified products. According to Reuters, the first compatible electronics could start appearing on store shelves by the end of this year.

Alliance chairman Sony's Scott Smyers said: "When consumers go to a store, they aren’t exactly sure what they're looking at – and that problem isn’t going away. The products aren’t getting less complicated – they're actually getting more complicated."

The Reuters report states that the group of 145 companies, including Microsoft and Sony, found consensus in common and existing standards for audio, video and Internet communications, but it has yet to agree upon an anti-piracy technology for movies and music.

Vice chairman of the technology alliance Microsoft's Pat Griffis said: "The whole copy protection issue is an order of magnitude more complex than anything we've done so far."