One Microsoft Way, Redmond, USA WA 98052;Faculty of Computer Science, Otto von Guericke University Magdeburg, Magdeburg, Germany 39016;School of Computing Science, Telecommunications Information Systems, DePaul University, Chicago, USA IL 60604;College of Information Science and Technology, Pennsylvania State University, University Park, USA PA 16802;Department of Computer Science, University of Massachusetts, Amherst, USA MA 01003;Computer Engineering and Computer Science Department, University of Louisville, Louisville, USA KY 40292;Department of Computer Science and Engineering, University of Minnesota, Minneapolis, USA MN 55455;College of Information Sciences and Technology, The Pennsylvania State University, Unversity Park, USA PA 16802