CONFERENCES

Karaenke P., Kirn St., A Multi-tier Negotiation Protocol for Logistics Supply Chains, Proceedings of the 18th European Conference on Information Systems (ECIS 2010), Pretoria, South Africa, June 7-9, 2010.

Logistics supply chains are characterized by multiple service providers contributing to the provision of a composite logistics service to a customer. In particular, various contractual dependencies exist across supply chain levels. The object of our research is resource allocation which has to consider these dependencies to avoid overcommitment and overpurchasing. We propose a multi-tier negotiation protocol for solving this problem. The proposed artifact is developed from an interaction protocol engineering perspective in accordance with the design science paradigm. First evaluation experiments show that the protocol prevents overcommitments and overpurchasing, leading to higher expected profits for logistics service providers.

Karaenke P., Kirn St., Towards Model Checking & Simulation of a Multi-tier Negotiation Protocol for Service Chains., In: Proceedings of the 9th International Joint Conference on Autonomous Agents and Multiagent Systems (AAMAS 2010), Toronto, Canada, May 10-14, 2010.

The object of our research is resource allocation which considers contractual dependencies across service chain tiers to avoid overcommitment and overpurchasing. We propose a multi-tier negotiation protocol for solving this problem. The proposed artifact is developed from an interaction protocol engineering perspective and a protocol specication is given. Besides basic safety properties like the absence of deadlock, we formally verify that the protocol prevents overcommitments and overpurchasing by means of the model checker Spin.

Karaenke P., Schuele M., Micsik A., Kipp A., Inter-organizational Interoperability through integration of Multiagent, Web Service, and Semantic Web Technologies., In: Proceedings of the Workshop on Agent-based Technologies and applications for enterprise interOPerability (ATOP 2010), Toronto, Canada, May 10, 2010.,

This paper presents a software architecture for inter-organizational multiagent systems. The architecture integrates multiagent technology with Web service technology to overcome the technical interoperability problem of current multiagent systems in the fast growing service-oriented environments. We integrate Semantic Web technology to overcome the semantic interoperability problem in cross-organizational service provisioning. We address the problem of interoperability regarding interfaces, messaging protocol, data exchanged, and security whilst considering a dynamic e-business environment. The proposed architecture enables service virtualization, secure service access across organizational boundaries, service-to-agent communication, and OWL reasoning within agents.

Iñigo Goiri, Ferran Julia, Jordi Guitart, and Jordi Torres, Checkpoint-based Fault-tolerant Infrastructure for Virtualized Service Providers, 12th IEEE/IFIP Network Operations and Management Symposium (NOMS'10), April 2010

Crash and omission failures are common in service providers: a disk can break down or a link can fail anytime. In addition, the probability of a node failure increases with the number of nodes. Apart from reducing the provider’s computation power and jeopardizing the fulfillment of his contracts, this can also lead to computation time wasting when the crash occurs before finishing the task execution. In order to avoid this problem, efficient checkpoint infrastructures are required, especially in virtualized environments where these infrastructures must deal with huge virtual machine images. This paper proposes a smart checkpoint infrastructure for virtualized service providers. It uses Another Union File System to differentiate read-only from read- write parts in the virtual machine image. In this way, read-only parts can be checkpointed only once, while the rest of checkpoints must only save the modifications in read-write parts, thus reducing the time needed to make a checkpoint. The checkpoints are stored in a Hadoop Distributed File System. This allows resuming a task execution faster after a node crash and increasing the fault tolerance of the system, since checkpoints are distributed and replicated in all the nodes of the provider. This paper presents a running implementation of this infrastructure and its evaluation, demonstrating that it is an effective way to make faster checkpoints with low interference on task execution and efficient task recovery after a node failure.