Delivery Context Ontology FAQ

Delivery Context Ontology (DCO) Frequently Asked Questions (FAQ)

What is the DCO?

The Delivery Context Ontology defines a set of characteristics for a device so that a device may most effectively interact with the Web or other services. These characteristics are defined in a formal model which represents the device, the software, and the network environment. Eventually this model will be expanded to address personalization characteristics.

The Delivery Context Ontology can be used to aide a service in delivering content that best meets the environment it may delivered in. Having a common vocabulary of characteristics is essential.

What are some use cases for the DCO?

• Video delivery in low bandwidth conditions - Imagine delivering a video stream in low bandwidth conditions. Delivering a high resolution video may result in pauses in delivery frustrating the user. By providing network characteristics a video service provider may provide a lower resolution version of the video.

• Ability to deliver content based on the device location - It may be important to provide location information about your device for situational applications, such as map tracking systems to provide a user with location information. These characteristics are defined in the DCO.

• Ability to know what binary formats are supported by a device - The content provider may need to provide alternative binary formats such as MPEG-3 vs. MPEG-4 based on characteristics of the device.

• The Device Description Repository API provides a means for an adaptive origin server to obtain information about a requesting device based on evidence that identifies the requesting device. The kind of information obtained from such a repository may vary from implementation to implementation, but properties that are uniquely identified should be equivalent across implementations. As an example, the DDWG drafted a Core Vocabulary that described a minimal set of properties that a DDR for content adaptation could provide, especially for the mobile Web use-cases. However, the definitions contained in the DDR Core Vocabulary are informally defined without reference to any agreed ontology. It is possible that other vocabularies may (inadvertently) define the same properties, creating unnecessary overlaps and potential conflicts or confusion. It was envisaged by the DDWG that the DCO would provide the necessary common reference point for all DDR vocabularies to avoid such problems.