The Digital Living Network Alliance (DLNA) launched its long-awaited program to certify that home network devices meet its interoperability guidelines. The first DLNA-certified products, eligible to bear the DLNA logo, are expected to hit the market by the end of 2005, the alliance said.
DLNA's mission is to make it possible for digital content to be shared seamlessly among PCs, consumer electronics and mobile devices in and beyond the home by setting minimum compatibility standards drawn from the PC and Internet industries.
At a minimum, DLNA-certified devices must incorporate Microsoft's UPnP technology for automatic device discovery, control and media management; they must use HTTP 1.0/1.1 for media transport; and they must use the IPv4 Protocol Suite for the network stack.
Mandatory multimedia formats are JPEG for images, PCM for audio and MPEG-2 for video. Devices need only incorporate the format that applies to them. An audio device, for example, doesn't have to incorporate ability to display JPEG images. A "rendering" device, such as a TV or PC, however, must incorporate all three at a minimum.
For connectivity, DLNA devices must incorporate 802.3i (10BaseT Ethernet) or 802.3u (100BaseT Fast Ethernet), or one of the Wi-Fi-certified 802.11 wireless standards (802.11a, b or g), or a combination of these physical-layer interfaces.
Despite the requirements, it is possible that select future DLNA devices might not be able to talk to one another because one device might have Ethernet only, another might have 802.11a only, and another certified device might have 802.11b/g only. Marketers, however, expect that the devices will incorporate wired Ethernet as a backup in wireless devices.
DLNA devices can also support the following optional media formats:
Imaging: GIF, TIFF, PNG.
Audio: MP3, WMA9, AC-3, AAC, ATRAC3plus.
Video: MPEG-1, MPEG-4, WMV9.
Since March 2004, DLNA hosted seven "plugfest" interoperability testing events in Asia, Europe and the United States to give its approximate 250 members a head start in designing products for eventual interoperability testing.
Select products are already marketed as having been "Designed to DLNA Guidelines.