8,046 research outputs found
A Software Infrastructure for Authenticated Web Metering
No full textAs the popularity of the Internet and the number of resources available on it have grown, potential customers are increasingly turning to it for information about products and services. Accordingly, online advertising is gaining a significant portion of the advertising market.
The Internet has become a mainstream advertising channel, surpassing traditional media such as newspapers and radio in number of advertisements. Many businesses, such as retail stores, travel agencies, airlines, and employment services, now depend on the Internet. According to an Interactive Advertising Bureau (IAB) report, Internet advertisers in the US spent almost $3 billion in the first six months of 2002, despite lower investments due to the economic and political environments.(1)
The same mechanisms ruling traditional advertising venues rule online advertising. Advertisers exploit the popularity of the best-known Web sites, typically search engines or portals, to advertise their products and reach the most potential customers. What is different is how advertisers measure ad exposure.
Traditional rating systems are of little value when applied to the Internet because of the enormous number of Web pages available to online advertisements. Counting accesses to a Web service is a difficult task and the data may be unreliable. Although the host servers usually collect the usage data, organizations might be tempted to inflate the number of registered accesses. Even a trusted host site can generate statistics that do not correspond to real usage.
Several metering techniques attempt to accurately measure the number of visits a site receives and hence the advertising exposure,(2,3) but advertisers and auditing companies haven't adopted a standard technique. Auditing companies base their measures of a Web site's popularity on statistics or market surveys.
We propose a framework based on hash chains.(4,5) Unlike similar approaches, our implementation minimizes the overhead associated with the additional communication required to implement the protocol while providing an efficient and flexible scheme. Furthermore, the resulting framework offers additional guarantees such as security and nonrepudiation of the produced proof of visits
A Simple Role Mining Algorithm
No full textComplex organizations need to establish access control policies in order to manage access to restricted resources. Role Based Access Control paradigm has been introduced in '90 years aiming at simplifying the management of centralized access control. The definition of a good set of roles in order to match the organizational requirements of a company is a problem partially solved by role mining techniques, which return automatically a set of roles compatible with the permissions assigned to users. Unfortunately, the problem of finding an optimal role set has been proved to be NP-hard; so heuristics have been introduced in order to approximate the optimal solution. In this work we propose a novel heuristic and compare its results showing its efficiency and effectiveness
Analysis and Design of Distributed Key Distribution Centers
No full textA Key Distribution Center of a network is a server who generates anddistributes secret keys to groups of users for secure communication. A Distributed Key Distribution Center is a set of servers that jointly realizes a Key Distribution Center. In this paper we describe in terms of information theory a model for Distributed Key Distribution Centers, and we present lower bounds holding in the model for the main resources needed to set up and manage a distributed center, i.e., memory storage, randomness, and bandwidth. Then we show that a previously proposed protocol which uses a bidimensional extension of Shamir's secret sharing scheme meets the bounds and is, hence, optimal
- …
