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Displaying 1-16 out of 16 total
Semi-Automatic Identification of Optic Disk by Image Processing for Quantitative Funduscopy
Found in: Graphics, Patterns and Images, SIBGRAPI Conference on
By Wilian Flavio Rigo, Aurelio Paulo Batista Da Silva, Thomas Walter Rauber
Issue Date:October 2002
pp. 18
This paper describes the current state of research and development of a system for the partial automation of quantitative Funduscopy. Image processing techniques are used to segment the optic disk and estimate the parameters of the circumference associated...
Formal Analyses of Usage Control Policies
Found in: Availability, Reliability and Security, International Conference on
By Alexander Pretschner, Judith Rüesch, Christian Schaefer, Thomas Walter
Issue Date:March 2009
pp. 98-105
Usage control is a generalization of access control that also addresses how data is handled after it is released. Usage control requirements are specified in policies. We present tool support for the following analysis problems. Is a policy consistent, i.e...
Usage Control Enforcement: Present and Future
Found in: IEEE Security and Privacy
By Alexander Pretschner, Manuel Hilty, Florian Schütz, Christian Schaefer, Thomas Walter
Issue Date:July 2008
pp. 44-53
Both personal data and intellectual property must be protected for various reasons. The authors explore the state of the art in usage control, which is about controlling the use of such data after it has been given away, and identify room for improvement.
Evidence Gathering for Remuneration of Shared Connections
Found in: Communication Networks and Services Research, Annual Conference on
By Thomas Walter, Christian Schaefer, Gina Kounga, Makoto Hamatsu
Issue Date:May 2008
pp. 569-576
At very popular events like music festivals or soccer games, base stations for mobile devices might be congested and, thus, are not able serving all mobile devices in their coverage. Thus, some mobile devices might be without connectivity to a mobile netwo...
Negotiation of Usage Control Policies - Simply the Best?
Found in: Availability, Reliability and Security, International Conference on
By Alexander Pretschner, Thomas Walter
Issue Date:March 2008
pp. 1135-1136
The term “negotiation” suggests that multi-step bidirectional communication takes place. In this position paper, we play the devil’s advocate and argue that (automated) policy negotiation essentially is one of the following, at least in the area of usage c...
Security in Pervasive Computing Calling for new Security Principles
Found in: International Conference on Pervasive Services
By Alf Zugenmaier, Thomas Walter
Issue Date:July 2007
pp. 96-99
No summary available.
DUKE--Distributed Usage Control Enforcement
Found in: Policies for Distributed Systems and Networks, IEEE International Workshop on
By Manuel Hilty, Alexander Pretschner, Christian Schaefer, Thomas Walter
Issue Date:June 2007
pp. 275
Usage control is concerned with what happens to data once the data have been released to a data consumer who is, in principle, able to use the data in any imaginable way. Considerations relating to privacy, intellectual property, and public security, howev...
Usage Control Requirements in Mobile and Ubiquitous Computing Applications
Found in: Systems and Networks Communication, International Conference on
By Manuel Hilty, Alexander Pretschner, Christian Schaefer, Thomas Walter
Issue Date:November 2006
pp. 27
Usage control is concerned with control over data after its release to third parties, and includes requirements such as
Service-oriented Accounting Configuration Management based on Diameter
Found in: Local Computer Networks, Annual IEEE Conference on
By Frank Eyermann, Peter Racz, Burkhard Stiller, Christian Schaefer, Thomas Walter
Issue Date:November 2005
pp. 621-623
<p>The increasing deployment of Universal Mobile Telecommunication System (UMTS) networks and WLAN (Wireless Local Area Network) hot-spots will shape the future development of wireless and mobile communication systems. The key objective of systems be...
Security and Trust Issues in Ubiquitous Environments — The Business-to-Employee Dimension
Found in: Applications and the Internet Workshops, IEEE/IPSJ International Symposium on
By Thomas Walter, Laurent Bussard, Philip Robinson, Yves Roudier
Issue Date:January 2004
pp. 696
<p>Ubiquitous applications and services combined with mobile business applications define a challenging context for security and trust. Besides the basic security requirements for controlled access, confidentiality, data integrity and accountability,...
A design process for embedding knowledge management in everyday work
Found in: Proceedings of the international ACM SIGGROUP conference on Supporting group work (GROUP '99)
By Kai-Uwe Loser, Marcel Hoffmann, Thomas Herrmann, Thomas Walter
Issue Date:November 1999
pp. 296-305
Knowledge Management Software must be embedded in processes of knowledge workers' everyday practice. In order to attain a seamless design, regarding the special qualities and requirements of knowledge work, detailed studies of the existing work processes a...
CPM: Masking Code Pointers to Prevent Code Injection Attacks
Found in: ACM Transactions on Information and System Security (TISSEC)
By Frank Piessens, Pieter Philippaerts, Stijn Muylle, Sven Lachmund, Thomas Walter, Yves Younan
Issue Date:June 2013
pp. 1-27
Code Pointer Masking (CPM) is a novel countermeasure against code injection attacks on native code. By enforcing the correct semantics of code pointers, CPM thwarts attacks that modify code pointers to divert the application’s control flow. It does n...
Filter-resistant code injection on ARM
Found in: Proceedings of the 16th ACM conference on Computer and communications security (CCS '09)
By Frank Piessens, Pieter Philippaerts, Sven Lachmund, Thomas Walter, Wouter Joosen, Yves Younan
Issue Date:November 2009
pp. 11-20
Code injections attacks are one of the most powerful and important classes of attacks on software. In such attacks, the attacker sends malicious input to a software application, where it is stored in memory. The malicious input is chosen in such a way that...
Breaking the memory secrecy assumption
Found in: Proceedings of the Second European Workshop on System Security (EUROSEC '09)
By Frank Piessens, Pieter Philippaerts, Raoul Strackx, Sven Lachmund, Thomas Walter, Yves Younan
Issue Date:March 2009
pp. 1-8
Many countermeasures exist that attempt to protect against buffer overflow attacks on applications written in C and C++. The most widely deployed countermeasures rely on artificially introducing randomness in the memory image of the application. StackGuard...
Accounting management for session mobility in an ubiquitous environment
Found in: Proceeding of the 2006 international conference on Communications and mobile computing (IWCMC '06)
By Christian Schaefer, Srisakul Thakolsri, Thomas Walter, Wolfgang Kellerer
Issue Date:July 2006
pp. 311-316
With the convergence of the Internet and the mobile communications world, Internet-based services may become available on any user device. In order to make efficient use of such a ubiquitous environment the user demands to access his personalized services ...
Generic accounting configuration management for heterogeneous mobile networks
Found in: Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots (WMASH '05)
By Burkhard Stiller, Christian Schaefer, Frank Eyermann, Peter Racz, Thomas Walter
Issue Date:September 2005
pp. 46-55
Accounting performed by network and service providers covers the tasks of determining, collecting, and evaluating information on the service usage of their customers. This information forms the basis of the subsequent charging process. For performing these...