Deutsche Telekom

About: Deutsche Telekom is a company organization based out in Welwyn Garden City, United Kingdom. It is known for research contribution in the topics: Telecommunications network & Signal. The organization has 3473 authors who have published 5208 publications receiving 65429 citations. The organization is also known as: DTAG & German Telecom.

Approximating the number of differences between remote sets

Abstract: We consider the problem of approximating the number of differences between sets held on remote hosts using minimum communication. Efficient solutions to this problem are important for streamlining a variety of communication sensitive network applications, including data synchronization in mobile networks, gossip protocols and content delivery networks. Using tools from the field of interactive communication, we show that this problem requires about as much communication as the problem of exactly determining such differences. As a result, we propose a heuristic solution based on the counting Bloom filter. We provide analytic bounds on the expected performance of our protocol and also experimental evidence that they can outperform existing difference approximation techniques.

CaMus2: collaborative music performance with mobile camera phones

Abstract: CaMus2 is a multi-user multi-phone extension of the CaMus system. Mobile camera phones use their cameras to track position, rotation, height, and other parameters over a marker sheet to allow interactive performance of music. Multiple camera phones can use the same or separate marker sheets and send their interaction parameters via Bluetooth to a computer where the sensor information is converted to MIDI format to allow control of a wide range of sound generation and manipulation hardware and software. The semantics of the mapping of MIDI message to performance parameters of the camera interactions are fed back into the visualization on the camera phone.

To Add or Not to Add: Privacy and Social Honeypots

Abstract: Online Social Networks (OSNs) have become a mainstream cultural phenomenon in the past years, where million of people connect to each other and share memories, digital media and business relations. Many users also publish personal information about their activities, relationships, locations and interests on these sites, seemingly unaware of how these data can be used by other parties. Sites typically attempt to restrict data-sharing to members of a user''s social network, but this is only effective if these social networks cannot be exploited by malicious users. In this paper we perform an experiment in order to assess the vulnerability and privacy awareness of users when engaging in online relations with random unknown users, or those pretending to be a famous character. We find that usually users do not accept random friendship requests, but some aggressively search for celebrities, making a perfect case for spammers to form honeypots using such fake profiles. We present a set of suggestions for enhancing privacy on social networks which could reduce the threats of identity theft in such environments.

Performance of P2P live video streaming systems on a controlled test-bed

Abstract: We evaluate and compare the performance of three P2P streaming systems that are capable of streaming live video on the Internet by testing them on a carefully controlled, traffic-shaped network test-bed. We first describe the construction of the test-bed based upon Internet measurements between geographically distributed hosts. Then, we present a methodology for evaluating these P2P video streaming systems by performing video quality and network usage analysis from the log information obtained via running these systems on the test-bed. Our methodology to assess P2P live video streaming systems comprises analyzing the objective quality of the received video, waiting time to receive the first data byte, and several network usage measures such as P2P protocol overhead, load on the server due to the inefficiencies of the P2P overlay, and measurements of the number of bytes exchanged between the peers. It is essential that every peer buffers packets for some time before playing out the video in order to ensure good quality. We report the time that the user has to wait before he can see the video playing. These measurements not only gauge the performance of currently available P2P streaming systems but also highlight desired improvements in current P2P video streaming systems.

Verfahren zur erkennung einer internationalen roaming-beziehung

Abstract: Die Erfindung betrifft ein Verfahren zur Erkennung einer internationalen Roaming-Beziehung zwischen einem Heimat-Mobilfunknetz und einem Fremd-Mobilfunknetz, wobei der Signalisierungsverkehr zwischen dem Heimat-Mobilfunknetz und dem Fremd-Mobilfunknetz uberwacht und aufgezeichnet wird, und aus diesen Signalisierungsdaten die Identitat des Gastteilnehmers und das besuchte Fremd-Mobilfunknetz ermittelt wird. Anhand der ermittelten Identitat des Teilnehmers kann eine gezielte Benachrichtigung des Teilnehmers in Form einer Informationsnachricht oder einer Begrusungsnachricht erfolgen, die es dem Gastteilnehmer ermoglicht, sich besser im Fremd-Mobilfunknetz zu orientieren.