Vladimir Zbarsky

Grammar-based task analysis of web logs

The daily use of Internet-based services is involved with hundreds of different tasks being performed by multiple users. A single task is typically involved with a sequence of Web URLs invocation. We study the problem of pattern detection in Web logs to identify tasks performed by users, and analyze task trends over time using a grammar-based framework. Our results are demonstrated on a corporate Intranet portal application with 7000 users over a 6 week period and demonstrate compelling business value from this high-level task analysis.

Enabling secure distribution of digital media to SD-cards

As the marketplace for digital media increases we witness the rise of new media distribution models where timely delivery, convenience, privacy and personalization are essential features of competitive offerings. Consumers are looking for innovative ways to access content in a service-oriented manner that suits their mobile life style. This paper describes a prototype standard-based system that allows the secure and fast download of content to SD-Card-enabled consumer devices. Content is protected by Content Protection for Recordable Media (CPRM) technology; specifically we use CPRM SD-Video. Our prototype shows Digital Media Terminals (DMT, also denoted kiosks) that enable innovative rental and purchase models. Our solution combines IBMs plug-in web services, Panasonics leading-edge devices and Porto Medias high-speed data transfer to Secure Digital Memory Flash Cards (SD-Cards).

Enabling secure digital marketplace

The fast development of the Web provides new ways for effective distribution of network-based digital goods. A digital marketplace provides a platform to enable Web users to effectively acquire, share, market and distribute digital content. However, the success of the digital marketplace business models hinges on securely managing the digital rights and usage of the digital content. For example, the digital content should be only consumable by paid users. This paper describes a Web-based system that enables the secure exchange of digital content between Web users and prevents users from illegally re-sell of the digital content. Part of our solution is based on broadcast encryption technology.

On business activity modeling using grammars

Web based applications offer a mainstream channel for businesses to manage their activities. We model such business activity in a grammar-based framework. The Backus Naur form notation is used to represent the syntax of a regular grammar corresponding to Web log patterns of interest. Then, a deterministic finite state machine is used to parse Web logs against the grammar. Detected tasks are associated with metadata such as time taken to perform the activity, and aggregated along relevant corporate dimensions.