203,341 research outputs found

    You never surf alone. Ubiquitous tracking of users' browsing habits

    Get PDF
    In the early age of the internet users enjoyed a large level of anonymity. At the time web pages were just hypertext documents; almost no personalisation of the user experience was o ered. The Web today has evolved as a world wide distributed system following specific architectural paradigms. On the web now, an enormous quantity of user generated data is shared and consumed by a network of applications and services, reasoning upon users expressed preferences and their social and physical connections. Advertising networks follow users' browsing habits while they surf the web, continuously collecting their traces and surfing patterns. We analyse how users tracking happens on the web by measuring their online footprint and estimating how quickly advertising networks are able to pro le users by their browsing habits

    MANAGING QUERY AND UPDATE TRANSACTIONS UNDER QUALITY CONTRACTS IN WEB-DATABASES

    Get PDF
    In modern Web-database systems, users typically perform read-only queries, whereas all write-only data updates are performed in the background, concurrently with queries.For most of these services to be successful and their users to be kept satisfied, two criteria need to be met: user requests must be answered in a timely fashion and must return fresh data. This is relatively easy when the system is lightly loaded and, as such, both queries and updates can be executed quickly. However, this goal becomes practically hard to achieve in real systems due to the high volumes of queries and updates, especially in periods of flash crowds. In this work, we argue it is beneficial to allow users to specify their preferences and let the system optimize towards satisfying user preferences, instead of simply improving the average case. We believe that this user-centric approach will empower the system to gracefully deal with a broader spectrum of workloads.Towards user-centric web-databases, we propose a Quality Contracts framework to help users express their preferences over multiple quality specifications. Moreover, we propose a suite of algorithms to effectively perform load balancing and scheduling for both queries and updates according to user preferences. We evaluate the proposed framework and algorithms through a simulation with real traces from disk accesses and from a stock information website. Finally, to increase the applicability of Quality Contracts enhanced Web-database systems, we propose an algorithm to help users adapt to the Web-database system behavior and maximize their query success ratio

    Online Journals: Utility of ToCs vs. Fulltext

    Get PDF
    The Caltech Library System (CLS) has maintained an extensive list of online journal websites for several years. The online journal list has grown to over 3000 entries, representing a mixture of free and subscription-based fulltext journals, as well as websites featuring tables of contents and abstracts. During the winter of 1999/2000, the online journals list was converted to an online journals database. Additional user functionality was added, without loss of previous features. In a previous study, search engines were employed to map the adoption rates of online journals into the web pages of research groups and individuals on the Caltech campus. It was established that the vast majority of online journal use on-campus was through the access avenues presented by the library, the online catalog and the online journals database. One of the new features introduced in the online journals database was an ability to limit displays to journals containing fulltext. Anecdotal evidence has been less than clear-cut with regard to the utility of non-fulltext resources. This study will allow for a thorough analysis of the question with hard data. It should be feasible to determine if there are discipline-based preferences or if personal preferences are the controlling factor. Analysis of the web server logs will also allow for a direct comparison of user preferences for searching and browsing. Again, we expect to be able to determine if there is a subject-specific bias or if behaviors are more individually idiosyncratic. Results of the study will inform the further development of the CLS online journal efforts - database development, online journal promotion, new candidates for licensing. The technologies employed in this project are well documented and may be exploited by other libraries seeking to gather empirical data for collection decisions and web development efforts

    Every Cloud Has a Push Data Lining: Incorporating Cloud Services in a Context-Aware Application

    Get PDF
    We investigated context-awareness by utilising multiple sources of context in a mobile device setting. In our experiment we developed a system consisting of a mobile client, running on the Android platform, integrated with a cloud-based service. These components were integrated using pushmessaging technology.One of the key featureswas the automatic adaptation of smartphones in accordance with implicit user needs. The novelty of our approach consists in the use of multiple sources of context input to the system, which included the use of calendar data and web based user configuration tool, as well as that of an external, cloud-based, configuration file storing user interface preferences which, pushed at log-on time irrespective of access device, frees the user from having to manually configure its interface.The systemwas evaluated via two rounds of user evaluations (n = 50 users), the feedback of which was generally positive and demonstrated the viability of using cloud-based services to provide an enhanced context-aware user experience

    CYCLOSA: Decentralizing Private Web Search Through SGX-Based Browser Extensions

    Get PDF
    By regularly querying Web search engines, users (unconsciously) disclose large amounts of their personal data as part of their search queries, among which some might reveal sensitive information (e.g. health issues, sexual, political or religious preferences). Several solutions exist to allow users querying search engines while improving privacy protection. However, these solutions suffer from a number of limitations: some are subject to user re-identification attacks, while others lack scalability or are unable to provide accurate results. This paper presents CYCLOSA, a secure, scalable and accurate private Web search solution. CYCLOSA improves security by relying on trusted execution environments (TEEs) as provided by Intel SGX. Further, CYCLOSA proposes a novel adaptive privacy protection solution that reduces the risk of user re- identification. CYCLOSA sends fake queries to the search engine and dynamically adapts their count according to the sensitivity of the user query. In addition, CYCLOSA meets scalability as it is fully decentralized, spreading the load for distributing fake queries among other nodes. Finally, CYCLOSA achieves accuracy of Web search as it handles the real query and the fake queries separately, in contrast to other existing solutions that mix fake and real query results
    • …
    corecore