The onset of the 6G era in telecommunications, touted to launch in 2030, is hoped to serve many masters and deliver an unparalleled improvement in capabilities, applications, intelligence, and indeed liberate human potential. The vision of 6G incorporates new radio frequencies and technologies, the integration of sensing, cognitive methods defining both network functions and their management, and new networking approaches for a broader scope of applications and distribution. The challenges for inventors lies in both physical devices and a substantive improvement in the development of functions implemented by, and managed, with software. The algorithms (including dynamic solutions based on Artificial Intelligence and Machine Learning), protocols, and architecture evolutions will bring together the most advanced software systems ever imagined for telecommunications. Yet, the business of companies building and operating these next generation platforms requires a huge investment, and 6G will exceed all others with its breadth and complexity. This paper outlines one possible timeline of technological impact based on the pace of invention, investment, global context, and the broad goals of 6G. From this, follows a vision of the critical methods in automation, security and networking that we believe will be central to bringing the dream of 6G to a reality.

Businesses in every industry are affected by progressing globalization and intensifying competition. Firms' leaders need skills to find new ways to create revenue and to evolve their business models continuously. Students should therefore be prepared to become tomorrow's firm leaders with education on business concepts in business transformation. This paper aims to analyze the effectiveness of introducing high school students to the concept of servitization with the serious game SwipeBike@TUM. SwipeBike@TUM was developed to apply business transformations in a game atmosphere while still be appealing at the same time. Within the game, the player takes up the role of C-Level Management to transform a bicycle manufacturer into a service provider through several business stages. The overall learning process is described by learning objectives and covers theoretical and practical parts. The evaluation with 29 students showed that SwipeBike@TUM improved their knowledge and self-evaluation of business models and transformation. For research, we contribute by demonstrating that serious gaming is a suitable teaching approach.

UAVs (Unmanned Aerial Vehicles) are candidates for serving as wireless access points in disaster or mass event scenarios. Here we elaborate on the question where to optimally place the available UAVs in space for a Poisson user distribution on the ground. Since the number of possible placement combinations is too high for a systematic search, we approach the optimal solution by a simple heuristic bio-inspired procedure. It turns out that changes in altitude contribute almost as much to increasing the average spectral efficiency as changes in horizontal directions. However, increasing the altitude requires much more energy than an equal movement in a horizontal direction. We show that restricting altitude movements by an attenuation factor can result in similar results as a procedure without such altitude restrictions. Even more intriguingly, keeping all UAVs at one favorable fixed altitude clearly outperforms the procedure with altitude flexibility. This has implications for the time UAVs can stay aloft with their on-board energy.

Voice over IP (VoIP) gains more and more attractiveness by large companies as well as private users. Therefore, the risk increases that VoIP systems get attacked by hackers. In order to effectively protect VoIP users from misuse, researchers use, e.g., honeynets to capture and analyze VoIP attacks occurring in the Internet. Global VoIP security threats are analyzed by studying several millions of real-world attacks collected in independent VoIP honeynet solutions with different capture mechanisms over a long period of time. Due to the validation of results from several honeynet designs we have achieved a unique, much broader view on large scale attacks. The results show similar attacker behavior, confirm previous assumptions about attacks and present new insights in large scale VoIP attacks, e.g., for toll fraud.

Mobile operators increasingly share their wireless networks to save cost. Some network parameters in the shared environment are operator-specific whereas others apply globally to all operators so their choice may lead to a disagreement between operators. We suggest that this problem can be solved by a voting system where operators cast weighted votes. We compare two weighting methods, namely the Proportional method and the so-called Penrose method for different operators' shares and benefits. We observe that the Penrose method performs especially well in cases where the foreseeable benefit of a decision is rather ambiguous for operators (in contrast, the distribution of operators' shares hardly influences which method is better). Even when operators' benefits of a decision are biased in one or the other direction according to a binomial distribution, the Penrose method performs better than the Proportional method overall. These findings are particularly relevant for multi-operator self-organizing networks (SON).

The deployment of pico cells to cover traffic hot spots within the footprint of a macro cell provides a powerful approach to meet the massive growth in traffic demands fueled by smartphones and bandwidth-hungry applications. Joint optimization of resource allocation and user association is critical to achieve the maximum capacity benefits and performance gains in such heterogeneous network deployments (HetNets). In order to gain insight in the achievable capacity gains, we examine in the present paper the stability and performance of a HetNet system in the presence of flow-level dynamics. The stability condition reveals that in stationary traffic conditions the maximum capacity can be achieved with a static resource split and traffic association rule, provided that these are suitably selected. This suggests that dynamic adaptation on time scales commensurate with the variations in traffic parameters suffices to extract most of the achievable capacity gains. For the case of static cell boundaries and Proportional Fair scheduling, we also present a method for evaluating the flow-level performance in terms of the distribution of the number of active file transfers and expected transfer delay.

Sharing mobile networks results in significant cost savings for operators, but limits competition due to loss of differentiation between operators. In this work we show that operators actually can differentiate even though they have to jointly take certain decisions, e.g., whether to activate or deactivate a shared small cell for energy efficiency purposes. The idea is to base the sharing agreement not on a fixed resource ratio, but to allow deviations from a more flexible baseline resource ratio that accommodate one operator's policy as long as the other operators' policies are not violated. We observe that activating additional small cells as a reaction to an increasing traffic demand can be delayed compared to the case with a strict resource ratio resulting in a significant energy saving.

MOTIVATION: Recent breakthroughs in protein residue-residue contact prediction have made reliable de novo prediction of protein structures possible. The key was to apply statistical methods that can distinguish direct couplings between pairs of columns in a multiple sequence alignment from merely correlated pairs, i.e. to separate direct from indirect effects. Two classes of such methods exist, either relying on regularized inversion of the covariance matrix or on pseudo-likelihood maximization (PLM). Although PLM-based methods offer clearly higher precision, available tools are not sufficiently optimized and are written in interpreted languages that introduce additional overheads. This impedes the runtime and large-scale contact prediction for larger protein families, multi-domain proteins and protein-protein interactions. RESULTS: Here we introduce CCMpred, our performance-optimized PLM implementation in C and CUDA C. Using graphics cards in the price range of current six-core processors, CCMpred can predict contacts for typical alignments 35-113 times faster and with the same precision as the most accurate published methods. For users without a CUDA-capable graphics card, CCMpred can also run in a CPU mode that is still 4-14 times faster. Thanks to our speed-ups (http://dictionary.cambridge.org/dictionary/british/speed-up) contacts for typical protein families can be predicted in 15-60 s on a consumer-grade GPU and 1-6 min on a six-core CPU. AVAILABILITY AND IMPLEMENTATION: CCMpred is free and open-source software under the GNU Affero General Public License v3 (or later) available at https://bitbucket.org/soedinglab/ccmpred.

The number of Voice over IP systems and the number of Session Initiation Protocol users is constantly increasing. The new Voice over IP infrastructures are connected with the traditional Public Switched Telephone Network and attacks against the phone infrastructure are becoming more imaginative. The attacks can cause financial losses, e.g., attackers steal money or incur costs for the victim. We analyze the current status of toll fraud attacks by analyzing real-world attacks collected in a Voice over IP honeynet solution. Based on the detailed data about real attacks, the creation or adaption of existing prevention mechanisms is possible in order to avoid toll fraud attacks in live environments.

Maximizing system throughput and bandwidth utilization while guaranteeing fairness among users is a core technical challenge in the design of next generation cellular networks. In this context, fractional frequency reuse (FFR) is a helpful tool if it is flexible in terms of resource and power allocation as well as scheduling. Complementary to this tool, a well-chosen association of users to base station sectors can yet be another important factor, particularly when users are distributed unevenly in space. Here we propose a load balancing scheme that combines flexible FFR with an unrestricted association of users to sectors or base stations, thereby effectively increasing the user data rates in the dense regions of the network. In a first step, we perform virtual joint power allocation and scheduling so as to determine the best sectors for maximizing the throughput for a given user. In a second step, users are actually associated to the best sectors, which are not necessarily the ones providing the strongest signal. Simulation results show that our proposed mechanism provides fairness by load balancing while still maintaining the throughput over all users.

An optimal vertical antenna tilt in a wireless access network plays a key role for coverage and capacity in the system. The autonomous (re-)optimization of tilts bears a large saving potential for operators as manual intervention is particularly costly. In this paper, we present a heuristic variant of the gradient ascent method to continuously optimize antenna tilts with quick convergence. We show that the average spectral efficiency in the system increases by 10% and that the spectral efficiency at the cell edge (5% quantile) increases by 100% after optimization. Changing conditions during the operational phase of the network, as for instance cell outage, can successfully be detected and compensated by an autonomous re-optimization.

Wireless mesh networks (WMNs) with inband backhauling use the same antennas for the backhaul as well as for the access. Therefore antennas of next hop neighbours need to be directed to each other. However, such a configuration is not possible in a three-sectorized hexagonal cell deployment. In this paper we derive several alternative topologies that are suitable for WMNs with inband backhauling. We show that a topology with four directional antennas per node and backhaul connectivity between indirect neighbours outperforms competing topologies in terms of handover rate, optimal maximum power, and system capacity.

SUMMARY: The performance of sequence database search methods is usually judged by receiver operating characteristic (ROC) analysis. The proper interpretation of the results obtained and a fair comparison across different methods critically depends on the properties of the data set used for such an analysis; in particular, each query must have the same number of true positives and true negatives. Here, we present a novel web service based on a dataset specifically designed for ROC analysis and the investigation of alignment quality. The data set is derived from a quantitative classification of protein structures (COPS), while analysis and results are presented through an intuitive web interface. The analysis provides details such as false positives per query, and visualization of the structural similarity between query and targets. Most importantly, results obtained for a specific alignment method are immediately related to those obtained for several popular standard sequence alignment methods.

EARTH is a major new European research project starting in 2010 with 15 partners from 10 countries. Its main technical objective is to achieve a reduction of the overall energy consumption of mobile broadband networks by 50%. In contrast to previous efforts, EARTH regards both network aspects and individual radio components from a holistic point of view. Considering that the signal strength strongly decreases with the distance to the base station, small cells are more energy efficient than large cells. EARTH will develop corresponding deployment strategies as well as management algorithms and protocols on the network level. On the component level, the project focuses on base station optimizations as power amplifiers consume the most energy in the system. A power efficient transceiver will be developed that adapts to changing traffic load for an energy efficient operation in mobile radio systems. With these results EARTH will reduce energy costs and carbon dioxide emissions and will thus enable a sustainable increase of mobile data rates.

MBMS (Multimedia Broadcast Multicast Service) is a service offered by 3GPP cellular networks for the distribution of multimedia content and can be transmitted by multiple base stations in a coordinated way such that signals from several base stations are perceived as one single signal at the user terminal. This requires synchronization of the radio interface on all layers so that all participating base stations have to apply the same transmission rules to the packets they obtain from the core network. These rules must be robust in the sense that synchronization is maintained even if some packets are not received by a base station. In this paper we propose a corresponding method that is capable of reliably accommodating the loss of an arbitrary number of consecutive packets even if statistical multiplexing is applied.

UNLABELLED: The database of known protein structures contains an overwhelming number of structural similarities that frequently point to intriguing biological relationships. The similarities are often difficult to spot, and once detected their comprehension needs proper visualization. Here we introduce the new concept of a Fold Space Navigator, a user interface enabling the efficient navigation through fold space and the instantaneous visualization of pairwise structure similarities. AVAILABILITY: The Fold Space Navigator is accessible as a public web service at http://services.came.sbg.ac.at