“DLNA is also looking to the future with VidiPath, including charting a course for providing bi-directional links between first screens, that is TVs and set tops, and second screens such as tablets and phones,” said Palm, who is also Senior Technical Director with fabless broadband and wireless chip maker Broadcom. DLNA was also looking at how to support cloud-sourced content in the context of dual screen operation. “This would enable consumers to launch cloud applications on one device under control of another and share this content to cloud-enabled DLNA HTML5 RUI devices with the same consistent service provider user experience,” said Palm.

This focus on HTML5 for second screens is in line with VidiPath. HTML5 has become more than just a web mark-up language but the effective video OS (operating system) for IP devices including smart TVs. VidiPath meanwhile is the DLNA’s new brand unveiled in September 2014 for its set of standards designed to enable video streams to be shared among and transmitted between connected devices such as TVs, PCs, tablets and game consoles with a common UI and with encryption based security deemed good enough for premium content. Rather than inventing new standards the DLNA has where possible incorporated existing ones, including Digital Transmission Content Protection over Internet Protocol (DTCP-IP) along with various authentication capabilities for security, IEEE 1905.1 and UPnP for automatic interoperability, network power save, adaptive delivery technology to optimise streaming quality, along with HTML-5 itself.

At the same time as coming out with the new brand DLNA announced its Certification program for VidiPath, essential for developing devices conforming with the DLNA standards. “The first Certified products are expected to hit retail shelves in Q1 2015, creating the opportunity to put more eyes on more subscription TV content on more devices than ever before,” said Palm.

The task of assembling VidiPath might have been easier if all these constituent standards had been fully defined at the outset but in the event many of them were still evolving themselves. This was particularly the case with HTML5, which has evolved in parallel with VidiPath. For that reason DLNA started out working with the preceding version HTML4, but this never really saw the light of day and in any case HTML5 was being designed specifically for video with many of the features DLNA would otherwise have had to develop anyway. So DLNA was quickly re-aligned with HTML5, although this brought complications because the standard was very broad in order to cater for all possible use cases and scenarios. “Due to the large scope of the HTML5 specification, and the need to fill open gaps in previous generations of DLNA technology, client and server devices had to be fairly complex,” said Palm. An additional complication was that DLNA had to incorporate authentication handshaking and encryption in order to provide sufficient protection for high-value video content and this made debugging of implementations especially complex. “There are also significantly more mandatory features in VidiPath than in earlier Guidelines, to help drive the consistency of experience that paying subscribers expect from their service providers,” Palm added.

This meant HTML5 itself was only addressing a subset of the use cases DLNA was envisaging and this meant the VidiPath certification program had to be even larger and more complex still. “The owner of HTML5, W3C, had a few basic HTML5 test cases, but DLNA had to create and optimize many for VidiPath,” said Palm.

The bulk of this work has been done in collaboration with CableLabs, the R&D body for the cable TV industry. “We hosted a number of interoperability events and tutorials to allow a large number of entrants to make progress on their implementations,” said Palm. “This accelerated progress toward the end goal of a set of product guidelines that would best support content and service delivery and an optimized subscriber experience.”

Apart from complexity relating to interoperability the DLNA has had to contend with frictions between stakeholders, especially the two camps of service providers and CE (Consumer Electronics) vendors. Service providers wanted CE makers to deploy more extensive processing resources fit for rendering top quality guides and graphics, but the latter were reluctant to raise costs without proof that the DLNA standards and profiles really would gain widespread adoption.

According to Palm these tensions were gradually resolved as DLNA gained momentum and members identified a common need for a standard platform for IP video. “Most VidiPath development issues were contentious, but they became less so as use cases became more ubiquitous and there were fewer reasons for individual members companies to protect a given perceived competitive advantage,” said Palm. “Additionally, any challenges were generally outweighed by the compelling common need for an open content streaming solution that created market opportunity for CE manufacturers and solved the providers’ challenge of creating a better user experience and differentiation from their OTT competitors while simplifying service management.”