In recent years cheap Internet access has become increasingly popular within the industrialized countries. Especially in the age of Web 2.0, where popular Internet applications begin to dominate computer use, ubiquitous network access is more important than ever. A new class of networks aim to satisfy the demand for high bandwidth, low-cost, and ubiquitous Internet access: wireless mesh networks (WMNs). However, in order to reach a greater market penetration a fundamental factor must yet to be addressed: the ease of use. Except for small networks, manual configuration is infeasible, so robust autoconfiguration mechanisms are needed. To address this shortcoming of complicated setup procedures we introduce and evaluate a novel autoconfiguration protocol for WMN: the Dynamic WMN Configuration Protocol (DWCP). It deals with the assignment of unique addresses, the management of free and assigned addresses, the autonomous reaction to failures, and features support of conventional Dynamic Host Configuration Protocol (DHCP) clients. It is specifically suitable for large installations and was deployed and evaluated in a real testbed.

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Peer-To-Peer-systems (P2P) brought new methods to distribute large amounts of data to end users. The basic concept is to split larger data into chunks and distribute these chunks among peers so that each chunk can be requested from different peers instead of just one server. This allows increased distribution speed as resources from all participating peers are used, and therefore the workload on own resources is decreased. However, new security risks in terms of confidentiality, integrity, and availability need to be addressed. Security patterns targeted specifically for P2P-systems help designers to identify threats and show appropriate countermeasures.In P2P-systems a chunk's hash identifies the peer storing the chunk, and each peer is responsible for a specific range of the hash's keyspace. This mechanism is well established in P2P-software and solves routing problems. We introduce a new security pattern for P2P-systems that uses these hashes to guarantee the integrity of the distributed data even though chunks are sent to, received from, and stored by multiple, possible untrustworthy, peers.

Abstract. To allow for flexibility in software structures (architectures) especially plugins and agents are proposed solutions. While plugins are used to support the conceptual and practical issues within component oriented software environments, agents are used in software areas where social metaphors like (self-)adaptability, flexibility, mobility, interactivity etc. are of interest. Common to both approaches is a strong relation to a service-oriented view on exporting functionality. This contribution illustrates the idea of the integration of both concepts on the formal basis of high-level Petri nets.

Benjamin Schleinzer promoviert seit April 2008 am Lehrstuhl für Informatik 4 an der RWTH Aachen. Seine Promotion wird durch ein Stipendium von der Deutschen Forschungsgemeinschaft und von der BI-T Research School finanziert. Sein Diplom erlangte er 2008 von der Universität Hamburg. Im Rahmen seiner Dissertation beschäftigt er sich mit verteilten Dateisystemen für Wireless Mesh-Netzwerke. Christian Samsel ist Student der Informatik an der RWTH Aachen. Er arbeitete von 2008 bis 2010 am Lehrstuhl für Informatik 4 als studentische Hilfskraft am Projekt UMIC im Bereich Wireless Mesh-Netzwerke. Im Rahmen seiner Diplomarbeit entwickelte er Flowgrind weiter und ist im Moment der Hauptentwickler von Flowgrind.