Overview: Enjoying the Digital Revolution
The digital media revolution is captivating the imagination of consumers. Digital cameras, personal video recorders, MP3 audio players, HDTV displays, digital set-top boxes, and new generations of mobile devices and media center PCs are just a few of the products generating buzz in the world of consumer electronics (CE). The potential effect of increasingly popular IP home networks and broadband connections creates a vast opportunity for PC and CE device manufacturers, application developers, and content creators to deliver new uses and value for consumers.

As consumers acquire and store a growing variety of digital media content, they should be able to share and enjoy their music, photos, and video on a variety of connected devices at anytime and from anywhere in the home. This is the heart of the Intel digital home vision, and its ultimate success depends on a single word: interoperability. But interoperability requires standards.

Common Framework Needed
The problem today is that there are more than 70 separate industry standards and protocols, ranging from UPnP*, to MP3, 802.11*x, MPEG and more. The use of standards is important, and implementing them can be even more crucial to ensuring interoperability. Delivering a proprietary implementation involves a high degree of risk, not only now, but also going forward.

The Digital Living Network Alliance (DLNA*, initially created as the Digital Home Working Group in June, 2003 by Founders Intel, Sony, and Microsoft with 17 Adopter companies from the Consumer Electronics and Personal Computer Industry) has developed and is promoting the Home Networked Device Interoperability Guidelines v1.0 - a common interoperability framework for use by CE and PC vendors.  As the digital media revolution continues to grow, there are many opportunities for companies to design and implement products conformant to the DLNA Interoperability Guidelines and to integrate added value into those products that create a robust consumer experience with products designed to interoperate within the digital home.

Intel has developed a document that, in support of the DLNA Interoperability Guidelines, requires conformance to those Guidelines and provides additional implementation guidelines for technologies that further enhances the consumer experience when a PC is present on the home local area network.  The Intel® Networked Media Product Requirements (Intel® NMPR) v2.0 document defines implementation details for technologies such as the UPnP Remote User Interface (RUI), Intel eXtended Remoting Technology (XRT) and, when providing premium content, the Digital Transmission Content Protection over Internet Protocol (DTCP-IP) as licensed by the Digital Transmission Licensing Administrator (DTLA – http://www.dtcp.com). Intel® NMPR v2.0 position is to support the DLNA Interoperability Guidelines for all devices designed to take advantage of the exceptional value the PC is able to extend to interoperable connected devices on the home local area network.

Ease of Use
Technology products often find themselves in the “Returned – No Fault Found” category by many suppliers.  This typically occurs because the consumer finds the device too difficult to configure, setup or to use and often becomes frustrated with the experience and returns the device to the store. Product returns creates additional support costs.  Combined with falling retail prices the industry observes significant margin erosion and consequent inability of industry vendors to invest in innovation. As devices interact more with the personal computer and take on more complex functions, they are increasingly prone to the challenges associated with EoU.

In order to increase opportunities for consumer success with Intel® NMPR products, exceptional execution on EoU is required.  Developers must ensure appropriate attention is given to Ease of Use (EoU) practices to provide the best possible consumer experience when using the device.  Product success is improved through consistent use of EoU practices and should be a normal part of the criteria required for each phase of a product design cycle.

There have been several white papers, design guides, and tools developed to assist in assessing and improving the ease of use for products’ Out of Box Experience and initial use of each portion of the computing environment -- developed by the Ease of Use/PC Quality Roundtable, and publicly available on their website (http://www.eouroundtable.com). White papers are based on data (call center, usability, market research) collected from multiple participating companies, and outline key problem areas, desired user experience, and near- and long-term opportunities for improvement. There are design guideline companion documents for white papers, as well as other tools.

Benefits of Interoperability
It is almost impossible to understate the importance and value of interoperability for connected digital home devices. Consumers increasingly want to access digital media files from a variety of devices throughout the home. For example, users may want to distribute HDTV content from a set-top box or personal video recorder (PVR) to TVs in different rooms, or access JPEG photos, MPEG-4 videos or MP3 audio files that have been cataloged and stored on a media center PC.

The ability of CE devices and PCs to interoperate smoothly and simply is obviously one of the fundamental keys to a positive user experience. The failure of connected devices to work together as advertised can lead to support calls, product returns, and lost business for retailers, manufacturers, and content providers alike.

While the industry has gone to great lengths to develop UPnP guidelines, networking protocols, and data compression standards, actually implementing them remains the challenge. Going with a proprietary implementation can involve a great deal of time-consuming effort and also involves the substantial risk that the product may not work with another solution from a third-party vendor.

The digital media revolution requires interoperable CE products that are differentiated with value added technologies that drive consumer adoption.  Intel® NMPR v2.0 was written to enable development of product with baseline interoperability conformant to DLNA Interoperability Guidelines v1.0 and provide a very robust consumer experience by defining a set of product differentiating technologies that assist developers in delivering innovative digital home products.

Advantages of Intel® NMPR v2.0
Intel® NMPR v2.0 takes steps to assure a very robust consumer experience by clearly articulating the baseline requirements defined in the DLNA Interoperability Guidelines v1.0 necessary to enhance the consumer experience above baseline requirements. Intel® NMPR v2.0 then introduces a set of technologies that build upon the articulated baseline requirements that take the consumer experience to the next level – specifically, UPnP RUI with an associated out-of-band delivery protocol, Intel XRT.  Further, Intel has assured a thorough enjoyment opportunity for the consumer be providing a mechanism by which the consumer may view and/or listen to premium content anywhere in their home as delivered by the PC on the home local area network.  The barrier to enjoying premium content has been a requirement to protect that content from unauthorized access or copying.  Intel has mitigated this barrier by enlisting DTCP-IP as the preferred content protection mechanism when sharing premium content on the home local area network.

Technologies Found inside Intel® NMPR v2.0

DTCP-IP

DTCP-IP* is a common industry specification with endorsements from content creators.  DTCP-IP is a link protection protocol used to encrypt content for transmission from where it is stored on the home network to where it is decrypted for viewing, listening and/or recording.  DTCP-IP is suitable only for short-range transmission of content across a local area network such as that found in the home. DTCP-IP seeks to circumvent unauthorized copying of content during transmission.

Premium content delivered to the home may be encrypted and have certain associated rights for viewing and/or copying.  The encryption scheme and the associated rights are referred to as Digital Rights Management (DRM).  There are a number of proprietary DRM technologies used to deliver premium content to the home – none interoperable with any other DRM.  Examples of DRMs may include conditional access mechanisms incorporated by cable and satellite distribution systems or technologies developed to deliver premium content to personal computers in a home via a broadband Internet connection.  Another type of DRM is Content Scramble System (CSS) used in commercial Digital Versatile Disk (DVD) production.

The DTLA provides a definition for premium content in the “Digital Transmission Protection License Agreement” (Section 2, clause 2.3 of Exhibit B).  In summary, commercial entertainment content (a.k.a. premium content) is audio, video, text and/or graphics that has not been created by the user of DTCP-IP, available for commercial purchase on a general basis, and includes some control method for delivery and, or, use. Examples include:

1. Video content made available for commercial purchase as available on a Digital Versatile Disk (DVD) protected from illicit copying by CSS;

2. Video and, or, audio content available for commercial purchase and delivery via the Internet that has been protected by a digital rights management scheme so as to prevent unauthorized use;

3. Video and, or, audio content available for commercial purchase via a cable distribution system that is protected from unauthorized access by a conditional access method.

DTCP-IP Source

A consumer may be presented with a variety of DRM schemes when subscribing to different sources of premium content.

Content protected by known (and future) DRM schemes should be brought together into a secure location where it may be transcrypted from the original DRM into a common, single copy protection mechanism that preserves the digital rights information of the original DRM.  DTCP-IP is the protocol that will be used to protect premium content in transit on the home network.

The PC, Set-top-box (STB), or other device with sufficient computing capability are examples of devices capable of consolidating content protected by DRMs and transcrypting from the DRM into DTCP-IP for distribution on the home network.  Such devices provide a source of DTCP-IP protected premium content for distribution to rendering and/or recording devices on the home network.

DTCP-IP Sink

Without a standard content-protection transmission technology a rendering device would require an implementation of all DRMs used to protect premium content.  Such a device may have limited market appeal due to excessive cost as both a stand-alone device and/or an integrated module. Additionally, premium content protected by a future DRM technology may not be render-able on devices already in the field unless they included a mechanism for in-field updates.

The computing device on the home network may accept premium content that may be protected by a variety of DRM technologies.  The computing device transcrypts from the DRM technology to DTCP-IP and then transmits the content to an authorized DTCP-IP rendering device.  Integrating DTCP-IP into a device enables it to receive all premium content from the computing devices on the home network.  Implementing a single, standard copy protection mechanism lowers cost – whether for a stand-alone rendering device, such as a digital media adapter (DMA) or a module for integration into a more traditional consumer electronics device, such as a television or DVD player.

UPnP RUI

UPnP Remote User Interface (RUI) is an open standard developed by the UPnP Forum and is available now for review and implementation (http://www.upnp.org/). UPnP RUI allows an application and it's user interface (UI) to be executed on different platforms. Utilizing the UPnP RUI capability on PCs and TV-connected Digital Media Player (DMP) devices for example, allows the PC to deliver hundreds of new services and content channels to the TV, in addition to those already available from the set top box. Wireless devices, in particular, greatly benefit from the deployment of UPnP RUI.

UPnP Remote UI Standard — Overview

The UPnP Remote UI Server functions in a manner very similar to a UPnP AV Media Server Content Directory Service in that it principally exposes Extended Markup Language (XML) listings containing Uniform Resource Identifiers (URI) that correspond to remote-capable applications. A UPnP RUI Client device functions in a manner similar to a UPnP AV Media Renderer in that it can accept requests from a control point to connect to a specified, remoted[1] user interface. The UPnP RUI Client additionally possesses the ability to initiate locally a connection by selecting from a listing of UIs pushed to it from a client control point. A UPnP RUI client can also receive text messages pushed by a control point. Finally, a UPnP RUI client can marshal and forward key input from another device.

UPnP RUI requires at least one common, peer-to-peer remote transfer communication protocol to be supported for basic device interoperability.  UPnP does not define the remote transfer protocol, therefore, the remote transfer protocol is considered to be “out-of-band” with respect to the UPnP device.

Once connected, a remoted application and a UPnP RUI client device employ the out-of-band communication protocol to transmit I/O events (key presses, display updates, etc.). As with media formats in UPnP AV, the UPnP RUI Device Control Protocol (DCP) does not specify any particular out-of-band protocol as required for compliance with the UPnP RUI specifications. UPnP RUI only defines a standard action that allows a client device to enumerate its supported protocols. This is done for the purpose of checking compatibility with application listings. Intel® NMPR v2.0 however, requires all Intel® NMPR v2.0-conformant UPnP RUI client devices to support Intel XRT2.1 remoting protocol as baseline capability, to ensure a minimum level of interoperability.

UPnP RUI Server Device

The UPnP RUI Server supports a single UPnP device service that allows control points to browse listings of applications that are remote-capable. In addition, the UPnP RUI Server is a virtual device, serving listings of application UIs. The URIs identifying the application may be associated with other devices within the home network. The listings are composed of user-friendly metadata, URIs identifying the remote-able application user interfaces, and optional application and protocol-specific technical information for each UI. The form of the returned listings is XSD schema-based XML. In creating a request for listings, a UPnP RUI Server may be requested by a UPnP RUI Server control point to only expose listings of remote-capable applications that employ a specific remoting protocol (for example, Intel XRT2.1). The control point may further request the UPnP RUI Server to only return listings that match the contents of some specific metadata field (for example, name="*chess*"). Finally, the UPnP RUI Server enables a UPnP RUI Server control point to set/get the connection initialization policy for a given application. (For example, whether or not connecting to a URI will result in a 'fresh' application state, or an in-progress application state.)

UPnP RUI Client Device

The UPnP RUI Client supports a single UPnP service that allows control points to set up and manage connected UI sessions on a given client.  The UPnP UI Client service allows a UPnP RUI client control point to post listings of client device-compatible remoted user interfaces directly to the client itself. UPnP RUI Client devices may support receiving simple text messages from UPnP RUI control points. UPnP RUI Clients may support the ability to receive key input from another network device. This capability allows a UPnP RUI Client to act as a proxy for another network device with respect to the remoted application.

UI Discovery and Connection Models

The UPnP RUI Device Control Point (DCP) allows for many models for the discovery of remote-capable UIs and connecting them to RUI client devices.

The Intel® NMPR v2.0 client discovery and connection model requires that the UPnP RUI Client device support three optional client services (see Figure 1). There is no UPnP RUI Server service — only a UPnP RUI client control point is employed in this model. Intel® NMPR v2.0 client devices utilizing this discovery and connection model are generally higher-end, and may have interactive UIs. In this model, a UPnP RUI control point acquires UI listings (either through some out-of-band means or via browsing a UPnP RUI Server) and posts them directly to the UPnP RUI Client device. The posted listings appear overlaid on the device 'local' UI. The user executes a connection simply by selecting one of the listed UIs.

Figure 1. Intel® NMPR v2.0 client connection model

 XRT2.1

Similar to media format support in UPnP AV, UPnP RUI requires at least one common remote transfer protocol to be supported for basic device interoperability. XRT2.1 is an Intel-developed, binary protocol requiring only minimal overhead on remoting clients by utilizing the generally greater computational power available on remoting servers. XRT2.1 is a stateless protocol that does not require caching of UI elements and can be implemented with a comparatively small software stack. While device vendors may chose to support additional remoting protocols, requiring XRT2.1 support by Intel® NMPR v2.0 client devices effectively ensures an interoperability baseline among all client devices. Intel XRT 2.1 specification and sample implementation is available for free download on the Intel® Developer Network for the digital home

Tools to Get You There
Developing a product for Intel® NMPR validation is a matter of following four basic steps: design, implementation, debug/test, and validation (Figure 2). Joining the Intel® Developer Network for the digital home is the place to start. Members can download Intel® NMPR at no cost.

Figure 2. Intel® Networked Media Product Requirements development and test tools provides more than 20 tools for a comprehensive solution for building Intel® NMPR Validated products for the digital home

To speed the implementation of industry specifications such as UPnP, UPnP Audio Visual (AV), and UPnP RUI, Intel provides a comprehensive suite of development authoring tools consisting of ready-to-use object code that has been pretested for Intel® NMPR conformance.

The following tools are available for download at no cost:

• Intel® Authoring Tools for UPnP Technologies—based on the Microsoft .NET* Framework v1.1, and including the Intel Device Builder Tool for quickly building device and control point stacks for Linux*, Microsoft Windows*, and Microsoft Pocket PC* platforms.
• Intel® UPnP RUI Technologies—demonstrates how UPnP RUI enables a PC user interface to interact remotely with a UPnP-enabled device, such as a TV or Microsoft Pocket PC device. This package includes sample source code.
• Intel® Tools for UPnP Technologies—this Intel® evaluation toolkit is based on the Microsoft .NET Framework v1.1 and is designed to accelerate the development, testing and deployment of UPnP-compliant devices.

Transcoding is the process of converting one media format into another, enabling DMAs located around the home to consume images, audio and video stored on a PC in a variety of formats. DMAs are limited in the number of media formats they can directly support. Intel® Software for Media Transcoding enables the PC to convert media formats to make them playable by DMAs.

Support for network members also includes 10 hours of tutorial videos on UPnP technology and available Intel tools, prepared by the Intel senior development engineering team. Members of the Intel® Developer Network for the digital home also have access to a dedicated e-mail support hotline.

The Intel® Developer Network for the digital home also provides access to two other important tools:

• The Intel® Conformance Test Tool (CTT) measures the ability of products to function according to Intel® NMPR guidelines and includes an easy-to-use, automated, scripted, simple pass/fail reporting structure.
• The Intel® Interoperability Test Tool (ITT) measures the ability of a product under test to function with other conforming products in real-world user scenarios against reference Intel® NMPR conformant components.

Both Intel® CTT and ITT test tools (Figure 3) generate a log file. Once sent to Intel, the log file qualifies a solution for an optional listing in the online solutions catalog.

Figure 3. Two Intel Tools from the Intel Developer Network for the Digital Home

Achieving Intel® NMPR validation is a matter of following the steps and using the tools, and the results can be dramatic. Using the tools enabled one device manufacturer to go from a purely proprietary solution to an Intel® NMPR-validated solution in only three days.

Summary
Interoperability between networked devices is vital to the success of innovative products and solutions designed for the digital home, and so is delivery of a robust consumer experience. Confronted by the variety of industry standards, network protocols and media file formats that exist today, developers need industry standards for implementation to ensure that CE devices work together and meet consumer expectations.

Intel recognizes the strong requirement for interoperability and encourage all digital home product developers to design in conformance to the DLNA Interoperability Guidelines v1.0 and incorporate the advanced technologies defined in Intel® NMPR v2.0 to assure a robust consumer experience.

Designing and validating a digital home product to Intel® NMPR conformance places developers at the fore front with a compelling digital home product. Intel® NMPR conformance enables companies to meet conformance to DLNA Interoperability Guidelines v1.0 while taking advantage of interoperable implementation guidelines for leading technologies such as UPnP RUI and DTCP-IP.

Developers must ensure appropriate attention is given to implementing Ease of Use practices at each phase of the product development cycle so as to increase the chance of product success when the consumer interacts with the product during their first out-of-box-experience with the product

More Info
Visit the  Intel® Developer Network for the digital home Web site to learn more about the benefits of membership, including where to download the Intel® NMPR and a variety of development, test, and validation tools, white papers, and other time-to-market benefits available at no cost. By following a series of simple steps, developers can achieve interoperability while delivering compelling digital home products that provide a robust consumer experience with the PC on the home local area network.

Intel announced the preview release of building block products for Intel® NMPR v2.0 at the Fall 2004 Intel Developer Forum.

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