Mobile DTV Group Adds Conditional Access and Audience Measurement Guidelines

WASHINGTON: Updated guidelines for mobile DTV receiver manufacturers are now available. Conditional access and audience measurement information have been added to the “ATSC Mobile Receiver Profile Guidelines.”

The conditional access recommendation capitalizes on an encryption system created by a consortium of device makers and service providers—Open Mobile Alliance Digital Rights Management. The simplest configuration is to put the conditional-access system at a centralized head-end, the addendum says. A more complex option is to distribute the generation of encryption keys, necessary for users to access CA content. Doing so is costlier, but provides a more robust architecture that’s less vulnerable to network issues that could affect the descrambler.

The audience measurement addendum describes a two-part system leveraging a data client in each device, and data server systems used by the broadcasters. The fundamental unit of measure, the Consumption Data Unit, or CDU, is defined by when a user starts and stops watching a programming service. The CDU captures global positioning system data, where available, at the start and termination of the CDU. Data capture will occur independent of whether the user has registered for a specific service, though registration will be necessary for the collection of demographic information.

CDUs will be captures in devices with functionalities other than mobile DTV reception only when a mobile broadcast channel is tuned and the “receiver is actively rendering content.” Powering up on such devices will not be considered a “required-to-be-reported event.”

CDU information will be sent to the broadcast server in a configuration determined by the broadcaster—one or several, depending on the services offered. Default reporting will be weekly, but can be immediate, or triggered when the device’s CDU storage hits 80 percent.

The “Service Protection and Role of the Mobile DTV Trust Authority” conditional-access addendum is available here. “Audience Data Gathering & Reporting Recommendations,” is here