This book constitutes the refereed proceedings of the 9th International Workshop on Algorithms and Models for the Web-Graph, WAW 2012, held in Halifax, Nova Scotia, Canada, in June 2012. The 13 papers presented were carefully reviewed and selected for inclusion in this volume. They address a number of topics related to the complex networks such hypergraph coloring games and voter models; algorithms for detecting nodes with large degrees; random Appolonian networks; and a sublinear algorithm for Pagerank computations.

The World Wide Web has become part of our everyday life and information retrieval and data mining on the Web are now of enormous practical interest. The algorithms supporting these activities combine the view of the Web as a text repository and as a graph, induced in various ways by links among pages, links among hosts, or other similar networks. The aim of the 4th Workshop on Algorithms and Models for the Web-Graph (WAW 2006)wasto further the understanding of these Web-induced graphsand stimulate the developmentofhigh-performancealgorithmsandapplicationsthat use the graph structure of the Web. The workshop was meant both to foster an exchange of ideas among the diverse set of researchers already involved in this topic and to act as an introduction for the larger community to the state of the art in this area. The workshop program included invited keynote talks by Fan Chung-Graham (UCSD), Soumen Chakrabarti (IITB), Walter Willinger (ATT Research) and Filippo Menczer (Indiana). WAW 2006tookplaceonNovember30 andDecember 1 at the Ban?Inter- tionalResearchInstitute(BIRS),inBan?,Alberta(Canada).Itwasthefourthin a seriesof verysuccessful workshopson the Web graph.W AW 2002 (Vancouver) and 2004 (Rome) were held in conjunction with the Annual IEEE Symposium on Foundations of Computer Science (FOCS). WAW 2003 (Budapest) was held in conjunction with the 12th International World Wide Web Conference.

This book constitutes the thoroughly refereed post-conference proceedings of the 4th Workshop on Combinatorial and Algorithmic Aspects of Networking, CAAN 2007, held in Halifax, Canada, in August 2007, co-located with the 10th Workshop on Algorithms and Data Structures, WADS 2007.

The 10 revised full papers together with 2 invited lectures presented were carefully reviewed and selected from a total of 17 submissions. This workshop brings together mathematicians, theoretical computer scientists and network specialists in a fast growing area that is an intriguing intersection of computer science, graph theory, game theory, and networks. Main focus is on strategies for searching in networks, and for cleaning networks of unwanted intruders, on different routing strategies, and on scheduling and load balancing.