References of "Fusenig, Volker 40000216"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailVerification of Data Location in Cloud Networking
Ries, Thorsten UL; Fusenig, Volker UL; Vilbois, Christian UL et al

in IEEE/ACM International Conference on Utility and Cloud Computing (2011)

Cloud computing aims to provide services and resources on a pay-as-you-use basis with additional possibilities for efficient adaptation of the required resources to the actual needs. Cloud networking ... [more ▼]

Cloud computing aims to provide services and resources on a pay-as-you-use basis with additional possibilities for efficient adaptation of the required resources to the actual needs. Cloud networking extends this approach by providing more flexibility in the placement, movement, and interconnection of these virtual resources. Depending on the use, customers however require the data to be located under a certain jurisdiction. To ensure this without the need of trusting the cloud operator, we propose a geolocation approach based on network coordinate systems and evaluate the accuracy of three prevalent systems. Even if the cloud operator uses supplemental measures like traffic relaying to hide the resource location, a high probability of location disclosure is achieved by the means of supervised classification algorithms. [less ▲]

Detailed reference viewed: 83 (1 UL)
Full Text
See detailAnonymity and Unlinkability in Electronic Communications
Fusenig, Volker UL

Doctoral thesis (2009)

Imagine a set of communication partners wants to keep their communication links secret. Consider the case where untrustworthy parties are able to observe every communication, which implies not only that ... [more ▼]

Imagine a set of communication partners wants to keep their communication links secret. Consider the case where untrustworthy parties are able to observe every communication, which implies not only that they can detect the content of the communication, but also who is communicating and who is listening. Using this information, the untrustworthy parties try to link communicating parties. This, in a nutshell, is the problem of anonymous and unlinkable communication in computer networks. By use of encryption techniques the content of messages can be kept private. However, the communication links can still be detected. Since the addresses of sending and receiving parties are contained in the header of every message sent over the network, an untrustworthy party needs only to eavesdrop a single message of the communication in order to link sender and receiver. Additional techniques have to be used to hide this information. We address this problem in this thesis. We define measures for anonymity and unlinkability that are based on the information theoretic notion of entropy. These measures are used first to evaluate different approaches for anonymous and unlinkable communication and second, to show the effectiveness of attacks on these protocols. We present existing techniques for anonymous and unlinkable communication and highlight weak points of these techniques by applying attacks to them. In these attacks, known as traffic analysis attacks, the attacker basically tries to collect as much information about the communication as possible and then makes deductions concerning the communication links. We show that these traffic analysis attacks are applicable to many existing techniques. Furthermore, we introduce a new traffic analysis attack, namely the slotted packet-counting attack. Motivated by these findings, we present a protocol for unlinkable communication in computer networks. We prove that this protocol leaks no information on communication links in the case where attackers are able to observe any communication in the network. By this means, the protocol guarantees a user-defined degree of unlinkability. We also show that the protocol generates a minimal amount of extra messages for achieving a given degree of receiver anonymity, i.e. where an attacker is not able to detect the receiver of a message. [less ▲]

Detailed reference viewed: 71 (3 UL)
Full Text
Peer Reviewed
See detailSlotted Packet Counting Attacks on Anonymity Protocols
Fusenig, Volker UL; Staab, Eugen UL; Sorger, Ulrich UL et al

in The proceedings of the Australasian Information Security Conference (2009)

In this paper we present a slotted packet counting attack against anonymity protocols. Common packet counting attacks make strong assumptions on the setup and can easily lead to wrong conclusions, as we ... [more ▼]

In this paper we present a slotted packet counting attack against anonymity protocols. Common packet counting attacks make strong assumptions on the setup and can easily lead to wrong conclusions, as we will show in our work. To overcome these limitations, we account for the variation of traffic load over time. We use correlation to express the relation between sender and receiver nodes. Our attack is applicable to many anonymity protocols. It assumes a passive attacker and works with partial knowledge of the network traffic. [less ▲]

Detailed reference viewed: 68 (4 UL)
Peer Reviewed
See detailUnlinkable Communication
Fusenig, Volker UL; Staab, Eugen UL; Sorger, Ulrich UL et al

in Privacy, Security and Trust, 2008. PST '08. Sixth Annual Conference on (2008)

In this paper we present a protocol for unlinkable communication, i.e. where an attacker cannot map the sender and receiver node of a communication. Existing anonymity protocols either do not guarantee ... [more ▼]

In this paper we present a protocol for unlinkable communication, i.e. where an attacker cannot map the sender and receiver node of a communication. Existing anonymity protocols either do not guarantee unlinkability (e.g. Tor and Mix networks), or produce huge overhead -- the dining cryptographers network causes quadratic number of messages. Our protocol needs only a linear number of messages while it still guarantees unlinkability. We introduce a measure of unlinkability and show that our protocol offers the highest possible degree of unlinkability. We show how to use the protocol in practice by adapting it to internet and ad hoc communication. [less ▲]

Detailed reference viewed: 90 (1 UL)