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 & Terminal (electronics). The organization has 3473 authors who have published 5208 publications receiving 65429 citations. The organization is also known as: DTAG & German Telecom.

Evaluation of Caching Strategies Based on Access Statistics of Past Requests

Abstract: Delivery of popular content on the Internet usually does not rely on a single server but is supported by content delivery networks (CDNs) that reactively store requested content in distributed cache servers. CDNs strengthen the availability and downloading throughput. Moreover, they shorten transport paths when caches in the proximity of requesting users are preferred. We study how the cache hit rate as the main efficiency criterion of web caches depends on the request statistics and the caching strategy that selects which content should be placed in or evicted from a cache. Although the least recently used (LRU) strategy seems to be widely deployed in web caches, our comparison in simulations and analytic case studies reveals essentially higher hit rates for alternatives based on the complete request statistics in the past under the realistic assumption of Zipf distributed user requests.

Method and device for the pseudonymization of digital data

Abstract: A system and method for pseudonymizing digital data records sent from a source system to a destination system, using an identity protector client system and an identity protector master system, includes the steps of receiving, at the identity protector client, person-specific data from a source system provided with a source identifier. The digital data records are pre-pseudonymized by the identity protector client, and the processed digital data records are marked with a source identifier which references the source file in the source system. The pre-pseudonymized digital data records are transmitted to the identity protector master. For every data record, a pseudonym is created by the identity protector master from the pre-pseudonym, the source identifier, and at least one other value generated from an erratic value and a time value. The pseudonym is transmitted to the destination system.

Process for distributing rate and power in a multicarrier transmission of a data stream

Abstract: A process for distributing an aggregate rate and total transmitting power of a data stream over a plurality of channels in which the sub-rate (R i ), capable of being transmitted over one channel, is calculated for each selected channel in accordance with the equation ##EQU1## R i being the sub-rate in the i-th channel, N i the average noise power first determined in the i-th channel, and D' being the number of actually used channels out of the channel group.

Addressing Use as Design: A Comparison of Constructivist Design Approaches

Abstract: Although there is often no straightforward relationship between theory and practice in design, it is necessary to articulate their mutual impact more clearly. Drawing on Wolfgang Jonas' generic model of design, a complete design process involves three domains of knowledge; namely analysis, projection and synthesis. For analysis, designers have adopted many methods from other disciplines, but it is not always obvious how they affect projection and synthesis.This is also the case when adopting a constructivist approach to design. Considering the ‘applicability gap’ between design analysis and projection, we are interested in how design practitioners deal with the increased uncertainty inherent in constructivism. To investigate the underlying assumptions about meaning construction, we compare four different design approaches, namely Participatory Design, Critical Design, Non-Intentional Design and Human-Centred Design. From the basic assumptions of each approach, we draw conclusions about how it addr...

The MacWilliams theorem for two-dimensional modulo metrics

Abstract: In this contribution the MacWilliams theorem is stated for codes over finite fields with two-dimensional modulo metrics.