TY - GEN AU - Robbert, Christoph ID - 492 TI - Ressource-Optimized Deployment of Multi-Tier Applications - The Data Rate-Constrained Case ER - TY - CONF AB - Within reactive topology control, a node determines its adjacent edges of a network subgraph without prior knowledge of its neighborhood. The goal is to construct a local view on a topology which provides certain desired properties such as planarity. During algorithm execution, a node, in general, is not allowed to determine all its neighbors of the network graph. There are well-known reactive algorithms for computing planar subgraphs. However, the subgraphs obtained do not have constant Euclidean spanning ratio. This means that routing along these subgraphs may result in potentially long detours. So far, it has been unknown if planar spanners can be constructed reactively. In this work, we show that at least under the unit disk network model, this is indeed possible, by proposing an algorithm for reactive construction of the partial Delaunay triangulation, which recently turned out to be a spanner. Furthermore, we show that our algorithm is message-optimal as a node will only exchange messages with nodes that are also neighbors in the spanner. The algorithm’s presentation is complemented by a rigorous proof of correctness. AU - Benter, Markus AU - Neumann, Florentin AU - Frey, Hannes ID - 496 T2 - Proceedings of the 32nd IEEE International Conference on Computer Communications (INFOCOM) TI - Reactive Planar Spanner Construction in Wireless Ad Hoc and Sensor Networks ER - TY - JOUR AU - Biermann, Thorsten AU - Scalia, Luca AU - Choi, Changsoon AU - Kellerer, Wolfgang AU - Karl, Holger ID - 769 IS - 8 JF - {IEEE} Communications Magazine TI - How backhaul networks influence the feasibility of coordinated multipoint in cellular networks ER - TY - CONF AB - The process of planning a virtual topology for a Wavelength Devision Multiplexing (WDM) network is called Virtual Topology Design (VTD). The goal of VTD is to find a virtual topology that supports forwarding the expected traffic without congestion. In networks with fluctuating, high traffic demands, it can happen that no single topology fits all changing traffic demands occurring over a longer time. Thus, during operation, the virtual topology has to be reconfigured. Since modern networks tend to be large, VTD algorithms have to scale well with increasing network size, requiring distributed algorithms. Existing distributed VTD algorithms, however, react too slowly on congestion for the real-time reconfiguration of large networks. We propose Selfish Virtual Topology Reconfiguration (SVTR) as a new algorithm for distributed VTD. It combines reconfiguring the virtual topology and routing through a Software Defined Network (SDN). SVTR is used for online, on-the-fly network reconfiguration. Its integrated routing and WDM reconfiguration keeps connection disruption due to network reconfiguration to a minimum and is able to react very quickly to traffic pattern changes. SVTR works by iteratively adapting the virtual topology to the observed traffic patterns without global traffic information and without future traffic estimations. We evaluated SVTR by simulation and found that it significantly lowers congestion in realistic networks and high load scenarios. AU - Wette, Philip AU - Karl, Holger ID - 508 T2 - Proceedings of the 19th IEEE International Workshop on Local and Metropolitan Area Networks (IEEE LANMAN) TI - On the Quality of Selfish Virtual Topology Reconfiguration in IP-over-WDM Networks ER - TY - CONF AB - In this paper we will introduce a new d-dimensional graph for constructing geometric application layer overlay net-works. Our approach will use internet coordinates, embedded using the L∞ -metric. After describing the graph structure, we will show how it limits maintenance overhead by bounding each node’s out-degree and how it supports greedy routing using one-hop neighbourhood information in each routing step. We will further show that greedy routing can always compute a path in our graph and we will also prove that in each forwarding step the next hop is closer to the destination than the current node. AU - Autenrieth, Marcus AU - Frey, Hannes ID - 509 T2 - Proceedings of the Conference on Networked Systems (NetSys) TI - On Greedy Routing in Degree-bounded Graphs over d-Dimensional Internet Coordinate Embeddings ER - TY - GEN AU - Splietker, Malte ID - 511 TI - MapReduce in Software Defined Networks ER - TY - CONF AB - Preemptive Routing and Wavelength Assignment (RWA) algorithms preempt established lightpaths in case not enough resources are available to set up a new lightpath in a Wavelength Division Multiplexing (WDM) network. The selection of lightpaths to be preempted relies on internal decisions of the RWA algorithm. Thus, if dedicated properties of the network topology are required by the applications running on the network, these requirements have to be known to the RWA algorithm.Otherwise it might happen that by preempting a particular lightpath these requirements are violated. If, however, these requirements include parametersknown only at the nodes running the application, the RWA algorithm cannot evaluate the requirements. For this reason an RWA algorithm is needed which incorporates feedback from the application layer in the preemption decisions.This work proposes a simple interface along with an algorithm for computing and selecting preemption candidates in case a lightpath cannot be established. We reason about the necessity of using information from the application layer in the RWA and present two example applications which benefit from this idea. AU - Wette, Philip AU - Karl, Holger ID - 520 T2 - Proceedings of the 32nd IEEE International Conference on Computer Communications (INFOCOM) TI - Incorporating feedback from application layer into routing and wavelength assignment algorithms ER - TY - GEN AU - Niklas Vinkemeier, Tim ID - 525 TI - Haptics - Hadoop performance testing in concurrent job scenarios ER - TY - GEN AU - Satya, Suhas ID - 534 TI - Emulating Wavelength Division Multiplexing using Openflow ER - TY - CONF AB - In Distributed Cloud Computing, applications are deployed across many data centres at topologically diverse locations to improved network-related quality of service (QoS). As we focus on interactive applications, we minimize the latency between users and an application by allocating Cloud resources nearby the customers. Allocating resources at all locations will result in the best latency but also in the highest expenses. So we need to find an optimal subset of locations which reduces the latency but also the expenses – the facility location problem (FLP). In addition, we consider resource capacity restrictions, as a resource can only serve a limited amount of users. An FLP can be globally solved. Additionally, we propose a local, distributed heuristic. This heuristic is running within the network and does not depend on a global component. No distributed, local approximations for the capacitated FLP have been proposed so far due to the complexity of the problem. We compared the heuristic with an optimal solution obtained from a mixed integer program for different network topologies. We investigated the influence of different parameters like overall resource utilization or different latency weights. AU - Keller, Matthias AU - Pawlik, Stefan AU - Pietrzyk, Peter AU - Karl, Holger ID - 562 T2 - Proceedings of the 6th International Conference on Utility and Cloud Computing (UCC) workshop on Distributed cloud computing TI - A Local Heuristic for Latency-Optimized Distributed Cloud Deployment ER - TY - GEN AU - Khan, Rana Azeem M. AU - Karl, Holger ID - 2504 TI - Simulating Cooperative Diversity Protocols for Multi-hop Wireless and Sensor Networks ER - TY - GEN AU - Dannewitz, Christian AU - Karl, Holger AU - Yadav, Aditya ID - 2505 TI - Report on Locality in DNS Requests – Evaluation and Impact on Future Internet Architectures ER - TY - CONF AU - Biermann, T. AU - Scalia, L. ID - 1805 SN - 9781424492688 T2 - 2011 IEEE Global Telecommunications Conference - GLOBECOM 2011 TI - Mobile WDM Backhaul Access Networks with Physical Inter-Base-Station Links for Coordinated Multipoint Transmission/Reception Systems ER - TY - CONF AU - Choi, Changsoon AU - Scalia, Luca AU - Biermann, Thorsten AU - Mizuta, Shinj ID - 1806 SN - 9781457713484 T2 - 2011 IEEE 22nd International Symposium on Personal, Indoor and Mobile Radio Communications TI - Coordinated multipoint multiuser-MIMO transmissions over backhaul-constrained mobile access networks ER - TY - JOUR AU - Biermann, Thorsten AU - Scalia, Luca AU - Choi, Changsoon AU - Karl, Holger AU - Kellerer, Wolfgang ID - 782 IS - 5 JF - Pervasive and Mobile Computing TI - CoMP clustering and backhaul limitations in cooperative cellular mobile access networks ER - TY - JOUR AU - Willig, Andreas AU - Karl, Holger AU - Kipnis, Danil ID - 783 IS - 2 JF - Wireless Networks TI - Segment-based packet combining: how to schedule a dense relayer cluster? ER - TY - CONF AU - Herlich, Matthias AU - Karl, Holger ID - 784 T2 - Proceedings of the 3rd International Conference on Energy-Efficient Computing and Networking, e-Energy'12, Madrid, Spain, May 9-11, 2012 TI - Average and competitive analysis of latency and power consumption of a queuing system with a sleep mode ER - TY - CONF AU - Blanckenstein, Johannes AU - Klaue, Jirka AU - Karl, Holger ID - 785 T2 - European Wireless 2012 - 18th European Conference 2012, April 18-20, 2012, Poznan, Poland. TI - Energy Efficient Clustering using a Wake-up Receiver ER - TY - CONF AU - Künsemöller, Jörn AU - Karl, Holger ID - 786 T2 - Economics of Grids, Clouds, Systems, and Services - 9th International Conference, GECON 2012, Berlin, Germany, November 27-28, 2012. Proceedings TI - On Local Separation of Processing and Storage in Infrastructure-as-a-Service ER - TY - CONF AU - Dräxler, Martin AU - Karl, Holger ID - 787 T2 - 2012 IEEE International Conference on Green Computing and Communications, Conference on Internet of Things, and Conference on Cyber, Physical and Social Computing, GreenCom/iThings/CPSCom 2012, Besancon, France, November 20-23, 2012 TI - Efficiency of On-Path and Off-Path Caching Strategies in Information Centric Networks ER -