HNTF/Home Network TF Discussions/CEA-2014 Overview
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CEA-2014 Web-based Protocol and Framework for Remote User Interface - Overview
CEA-2014 describes web based Remote UI applications for CE devices. CEA-2014 is referenced my multple Standards Development Organizations to provide ecosystem specific Remote UI solutions.
CEA-2014 leverages existing web technology standards including XHTML for screen layout and user interactions; and ECMAScript for interactive application support. In addition CEA-2014 provides additional standardardized interfaces in the following areas:
- Remote UI Application Listing
- Client Capabilities Matching
- Standardized Audio-Video Player
- Digital Rights Management Framework
- Content Download Management Framework
- UPnP / DLNA Home Network Framework
- SVG (Scalable Vector Graphics) integration with XHTML
- Server to Client Notification Framework
- Remote UI Save and Restore Framework
Remote UI Application Listing
CEA-2014 defines a mechanism for a Remote UI server to list available applications. This mechanism is based on an XML schema (XML UI Listing) which provides application descriptive metadata. In addition, a CEA-2014 server may include metadata for multiple versions of the same Remote UI application with differing client capability requirements. A Remote UI client system may then choose a version of a Remote UI application whch best matches its capabilities. See Client Capability Matching in the following section
Client Capabilities Matching
CEA-2014 defines XML metatata describing the capabilities of a connecting Remote UI client system. These capabilities include Input Support (Remote Control, Keyboard, etc), AV Player Capabilities, Client Display Capabilities (resolution, color space), Digital Rights Management capabilities. When a Remote UI client connects to a server, it will first examine the capability requirements of the Remote UI applications offered and will connect to a version that best matches its capabilities. During connection, the Remote UI Client provides its capabilities to the server. The server may modify the web-page provided to better match the connecting client's capabilities or may reject the connection if it cannot tailor the page to support the client's capabilities.
Standardized Audio-Video Player
CEA-2014 defines a standardized Audio-Video Player object. The AV Player object provides methods for control of AV playback (Play, Stop, Pause, Seek, Loop). In addition the AV player provides a "lock-out" mechanism disables end-users from skipping "required content". AV player callbacks are defined to notify web-pages of various playback related state-changes. The CEA specification defines a state-machine for the AV player so web-pages can rely on predictable AV player state transition behavior.
Digital Rights Management Framework
CEA-2014 defines a framework to allow a Remote UI application (web-page) to communicate with DRM Agent(s) installed on a Remote UI client. This DRM framework allows generic messaging between the web-page and DRM Agents installed on the Remote UI client.
Note: CEA-2014 does not define the specifics of any particular DRM system beyond listing of available Digital Rights systems in Remote UI client capabilities.
Content Download Management Framework
CEA-2014 defines a framework for Remote UI applications to initiate the download of content. Once the download process is started the Remote UI client switch to other Remote UI applications. In addition to providing status of download operations, CEA-2014 defines a Content Access Descriptor XML schema to describe content to be downloaded. Since Conten Access Descriptors are XML documents they may be associated with URLs and embedded into Remote UI applications.
UPnP / DLNA Home Network Framework
CEA-2014 defines a UPnP / DLNA binding so that web-pages can discover and control home network devices. The binding allows Remote UI applications discover, manage events and command UPnP and DLNA devices. In conjunction with the UPnP / DLNA Home Network Framework the Standardized AV Player is required to comply with DLNA media transport requirements for DLNA defined media formats. The combination makes CEA-2014 Remote UI clients suitable to support both both UPnP and DLNA applications.
The ability for Remote UI applications (originating from outside the home) to access home network devices presents significant security and privacy concerns. CEA-2014 requires implementation of a variety of security mechanisms to protect end-users Remote UI applications performing unauthorized access to Home Network devices.
SVG (Scalable Vector Graphics) integration with XHTML
CEA-2014 supports the embedding of SVG markup within XHTML pages and vice versa. CEA-2014 addresses some issues with regard to differing DOM models and event handling between SVG and XHTML resulting from the combination of SVG and XHTML content on the same web-page.
Server to Client Notification Framework
CEA-2014 provides the capabilities for servers to request Remote UI clients display web-pages. An "event" mechanism is defined so that Remote UI clients and servers can classify these Notification messages. In addition CEA-2014 clients may recover previously sent notifications that may have been missed while the Remote UI client was not present on the network.
Remote UI Save and Restore Framework
CEA-2014 provides a framework for a Remote UI application to save its state and POST it to a Remote UI server. The saved information consists of a reference to the original Remote UI application URL and metadata describing the saved state of the application. The save state may be restored by a different device effectively allowing the application to be moved to a different Remote UI client. The save-restore process may be triggered by the Remote UI application itself or by a request external to the Remote UI client.