DLNA for media streamers--what does it all mean?

We demystify the technical jargon and shortcomings of DLNA.

Matthew Panton Editorial Intern
4 min read


At CNET we've reviewed and covered a number of products designated "DLNA-certified," from game consoles to HDTVs, and in our experience the standard's idealistic vision, "to be able to easily and conveniently enjoy this content using any electronic device, and from any location in their home, and beyond," according to the DLNA's FAQ, sometime fails to come to fruition.

This failure can be blamed on numerous factors, including competing standards, Digital Rights Management issues, or manufacturers not entirely following the DLNA standard or eschewing it for their own. Confusion over what DLNA means can put buyers of media devices in a precarious situation: will my DLNA-certified Nokia N95 digital camera connect to my DLNA-certified Sony KDL-46Z4100 HDTV so I can share my photos of my trip to Maui for my family to view? In this blog I'll unravel some of the mysteries around DLNA and try to make sense of what it actually means.

Consumer electronics, computer and mobile device manufacturers want you, the end-consumer, to live in a digitally connected world populated by their products. The Digital Living Network Alliance (DLNA) began in 2003 as a collection of such companies (now over 250) with the "intended goal of agreeing on an interoperability framework and guidelines," as stated in its white paper, "denoting what media formats, delivery architecture, and network connectivity standards a device must follow to be certified." The goal is for you to go into any electronic store, look for a DLNA-certified product and buy it, knowing for certain that the technology ingredients used in that device will be compatible and future-proof in an ever expanding ecosystem of other devices, one of which you might already own. Unfortunately, DLNA often fails to deliver on that goal.

One problem is some of the standard's requirements are ambiguous or leave certain guidelines optional for manufacturers to implement into their devices. Here's an example from the DLNA white paper (PDF):

Media Formats Required Format Set Optional Format Set
Audio LPCM (2 channel) MP3, WMA9, AC-3, AAC, ATRAC3plus

DLNA does not include DivX, Xvid, FLAC or other popular formats in its guidelines. That means that one DLNA device, such as Pioneer's "Kuro" PDP-5020FD may support H.263 but another DLNA television may not.

Another problem is DLNA does not currently support a single Digital Rights Management (DRM) standard. The consortium states that "given the complexity of interoperability" with DRM, it has instead focused on protecting content while it's in transmission from device to device by using what it calls DLNA Link Protection. In this scenario, a user can only view content while it's streaming, but may or may not be able to record or save it to a trusted device, which some DRM standards already allow. This can become extremely confusing and problematic if you download DRM protected material from an Internet source and are unsure if your device can save it, let alone play it back.

And lastly, DLNA has failed largely to separate itself as a prevailing standard; other major manufacturers, such Apple, have not adopted it and have forced consumers into an Apple-centric universe. As such, FairPlay (DRM) music or videos will not playback on your DLNA HDTV unless you're utilizing Apple hardware, such as Apple TV.

Microsoft also has taken to "Apple-ization" by using its own standard, Device Profile for Web Service (DPWS), promoted by the company as Windows Rally (formerly Windows Connect Now). You might have used this to connect your Xbox 360 or Windows Media Extender to your PC by typing in a code. While it's an easy solution to share your media collection and web videos, like Apple, it will only work with compatible devices and not with DLNA-certified software like TVserity or TwonkyMedia.

The High-Definition Audio-Video Network Alliance (HANA) also has its own, competing standard, backed by Samsung, NBC Universal, and others, which the organization claims is built from the ground-up as an interconnecting structure for connecting together your DVR, HDTV, and satellite receiver, and other home AV components, allowing the user to operate them with one remote within one unified menu system. HANA has initially focused on IEEE 1394, also known as FireWire, to interconnect such devices, isolating the video and audio stream from the Internet by not using an Ethernet connection. This is, of course, for DRM purposes, but also FireWire is an isochronous connection, meaning it doesn't fluctuate in signal quality like a Wi-Fi connection might do, theoretically providing a higher quality HD picture as the end result. While we won't go further into the specifics, as it's beyond the scope of this article, suffice to say there no products on the market now (that we are aware of) that support the standard. For more information, refer to this in-depth article on the topic.

We'll cover Microsoft Rally and DLNA software more extensively in a later article, but what do you think? Do these competing standards hurt more than help the Utopian dream of having an all-connected digital life? And which one do you think should be the established one? Sound off in the comments below.