DAISY Online Delivery
This article is an introduction to the DAISY Online Delivery Protocol. The full protocol specification and other details can be found in the projects section of the DAISY consortium web site .
The DAISY Online Delivery Protocol has reached Recommendation Status by the DAISY Consortium.
The protocol was developed by the DAISY Online Working Group and is “a web service API that facilitates the delivery of digital resources from service providers to end users.” - taken from the abstract of the specification .
The protocol provides a standard API (Application Programming Interface) by which content providers can deliver Digital Talking Books – and other kinds of content - to user’s players via the internet. Delivery over the internet allows for more timely and cost-effective provision of content. Historically books have been delivered by mailing a physical media such as a compact disc or USB memory stick. As online delivery became more attractive a need for a standard protocol by which services and players from different organisations could communicate became increasingly desirable.
The ability to deliver content is a more timely manner is important for the provision of items such as daily newspapers.
The protocol specifies how a “reading system” (player) should communicate with a “service” (content provider). Both the reading system and service must support the DAISY Online Delivery Protocol
In order to connect to a service the reading system must have a web address for the service and a username and password with which to log in. These pieces of information would be provided by the service provider.
Communications between the reading system and service use HTTPS (Secure HyperText Transfer Protocol).
The protocol allows for content – books, magazines, etc – to be borrowed or purchased by the user. The choice of which method or methods are offered is made by the service provider.
The content can also be transferred using a secure transfer protocol.
The protocol allows the service to describe itself to the reading system and for the reading system to describe its capabilities to the service. This allows the service to only provide features that the reading system can present to the user. For example if the reading system has no way for the user to enter text then the service will not ask the user to do so.
The protocol supports two content selection methods:
- The out-of-band method by which the user selects contents using a method outside the protocol – such as a web site or by telephoning the service providers customer services staff.
- The browse method by which the user selects content using features on the reading system which utilises the protocol to browse or search the service’s catalogue.
The latter method requires more sophistication in the reading system such as the ability to enter text.
The protocol provides the ability for a service to communicate with the user through menus and questions. This communication requites that the reading system supports the dynamic menus feature of the protocol. Examples of this kind of communication are: browsing and searching the product catalogue; purchasing content and answering surveys.
Reading Systems and Services
At the time of writing the author is not aware of any publically available DAISY Online Delivery Protocol compliant reading systems and services but several members of the working group have developed proof-of-concept systems.
Developing Reading Systems and Services
Development platforms and tools used to build compliant reading systems and services must support the underlying technologies listed in the protocol specification .
The protocol uses WS-I Basic Profile 1.1  and the wrapped document-literal binding style.
1. DAISY Online Delivery Project web site: http://www.daisy.org/project/daisy-online-delivery.
2. Specification for the DAISY Online Delivery Protocol: http://www.daisy.org/projects/daisy-online-delivery/drafts/20100402/do-spec-20100402.html
3. WS-I Basic Profile 1.1: http://www.ws-i.org/Profiles/BasicProfile-1.1-2004-08-24.html
Text is available under the terms of the DAISY Consortium Intellectual Property Policy, Licensing, and Working Group Process.