Yahyapour, Ramin

[["dc.bibliographiccitation.firstpage","22"],["dc.bibliographiccitation.journal","Wissenschaftsmanagement"],["dc.bibliographiccitation.lastpage","25"],["dc.bibliographiccitation.volume","3"],["dc.contributor.author","Yahyapour, Ramin"],["dc.contributor.author","Wieder, Philipp"],["dc.date.accessioned","2021-10-22T11:05:45Z"],["dc.date.available","2021-10-22T11:05:45Z"],["dc.date.issued","2013"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/91228"],["dc.language.iso","de"],["dc.relation.orgunit","Gesellschaft für wissenschaftliche Datenverarbeitung"],["dc.title","Heiter bis wolkig"],["dc.title.subtitle","Cloud-Dienste für die Wissenschaft"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","335"],["dc.bibliographiccitation.lastpage","347"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Seidel, Jan"],["dc.contributor.author","Wäldrich, Oliver"],["dc.contributor.author","Ziegler, Wolfgang"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2020-04-06T14:35:45Z"],["dc.date.available","2020-04-06T14:35:45Z"],["dc.date.issued","2008"],["dc.identifier.doi","10.1007/978-0-387-78446-5_22"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63894"],["dc.relation.isbn","978-0-387-78445-8"],["dc.relation.isbn","978-0-387-78446-5"],["dc.relation.ispartof","Grid Middleware and Services"],["dc.title","Using SLA for Resource Management and Scheduling - A Survey"],["dc.type","book_chapter"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","91"],["dc.bibliographiccitation.lastpage","98"],["dc.contributor.author","Fatemi Moghaddam, Faraz"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2019-01-25T09:22:37Z"],["dc.date.available","2019-01-25T09:22:37Z"],["dc.date.issued","2017"],["dc.description.abstract","Security challenges are the most important obstacles for the advancement of IT-based on-demand services and cloud computing as an emerging technology. Lack of coincidence in identity management models based on defined policies and various security levels in different cloud servers is one of the most challenging issues in clouds. In this paper, a policy-based user authentication model has been presented to provide a reliable and scalable identity management and to map cloud users' access requests with defined polices of cloud servers. In the proposed schema several components are provided to define access policies by cloud servers, to apply policies based on a structural and reliable ontology, to manage user identities and to semantically map access requests by cloud users with defined polices. Finally, the reliability and efficiency of this policy-based authentication schema have been evaluated by scientific performance, security and competitive analysis. Overall, the results show that this model has met defined demands of the research to enhance the reliability and efficiency of identity management in cloud computing environments."],["dc.identifier.doi","10.1109/NOF.2017.8251226"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57383"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.conference","8th International Conference on the Network of the Future (NOF)"],["dc.relation.eventend","2017-11-24"],["dc.relation.eventlocation","London, UK"],["dc.relation.eventstart","2017-11-22"],["dc.relation.isbn","978-1-5386-0554-7"],["dc.relation.ispartof","8th International Conference on the Network of the Future (NOF)"],["dc.relation.orgunit","Gesellschaft für wissenschaftliche Datenverarbeitung"],["dc.title","A policy-based identity management schema for managing accesses in clouds"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","267"],["dc.bibliographiccitation.lastpage","273"],["dc.contributor.author","Yang, Song"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2019-02-08T09:13:33Z"],["dc.date.available","2019-02-08T09:13:33Z"],["dc.date.issued","2016"],["dc.description.abstract","In nowadays cloud computing systems, leveraging the virtualization technology, the customer's requested data computing or storing service is accommodated by a set of mutual-communicated Virtual Machines (VM) in a scalable and elastic manner. These VMs are placed in one or more datacenter nodes according to nodes' capacities, failure probabilities, etc. The VM placement availability refers to the probability that at least one set of the whole customer's requested VMs operates during the entire requested lifetime. The placed VMs should obey the agreed-upon availability, otherwise the cloud provider may face revenue loss. In this paper, we study the problem of placing at most H sets of k requested VMs on minimum number of datacenter nodes, such that the VM placement availability requirement is satisfied and each VM pair has a communication delay no greater than the specified. We prove that this problem is NP-hard. We subsequently propose an exact Integer Nonlinear Program (INLP) and an efficient heuristic to solve this problem. Finally, we conduct simulations to compare the proposed algorithms with two existing heuristics in terms of acceptance ratio, average number of used nodes and running time."],["dc.identifier.doi","10.1109/RNDM.2016.7608297"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57536"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.conference","8th International Workshop on Resilient Networks Design and Modeling (RNDM)"],["dc.relation.eventend","2016-09-15"],["dc.relation.eventlocation","Halmstad, Sweden"],["dc.relation.eventstart","2016-09-13"],["dc.relation.isbn","978-1-4673-9023-1"],["dc.relation.ispartof","2016 8th International Workshop on Resilient Networks Design and Modeling (RNDM)"],["dc.relation.orgunit","Gesellschaft für wissenschaftliche Datenverarbeitung"],["dc.title","Reliable Virtual Machine placement in distributed clouds"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Wäldrich, Oliver"],["dc.contributor.author","Ziegler, Wolfgang"],["dc.contributor.author","Papaspyrou, Alexander"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2020-04-03T16:36:29Z"],["dc.date.available","2020-04-03T16:36:29Z"],["dc.date.issued","2007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63717"],["dc.title","Novel Approaches for Scheduling in D-Grid: Towards an interoperable Scheduling Framework"],["dc.type","report"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","207"],["dc.bibliographiccitation.lastpage","221"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Wäldrich, Oliver"],["dc.contributor.author","Ziegler, Wolfgang"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2020-04-06T14:30:15Z"],["dc.date.available","2020-04-06T14:30:15Z"],["dc.date.issued","2008"],["dc.identifier.doi","10.1007/978-0-387-72812-4_16"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63891"],["dc.relation.isbn","978-0-387-72811-7"],["dc.relation.ispartof","Achievements in European Research on Grid Systems"],["dc.title","Improving Workflow Execution through SLA-based Advance Reservation"],["dc.type","book_chapter"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yahyapour, Ramin"],["dc.contributor.author","Ziegler, Wolfgang"],["dc.contributor.editor","Wieder, Philipp"],["dc.contributor.editor","Yahyapour, Ramin"],["dc.contributor.editor","Ziegler, Wolfgang"],["dc.date.accessioned","2018-08-16T13:38:33Z"],["dc.date.available","2018-08-16T13:38:33Z"],["dc.date.issued","2010"],["dc.description.abstract","As Grids and service-oriented architectures have evolved to a common infrastructure for providing and consuming services in research and commercial environments, mechanisms are needed to agree on the objectives and the quality of such service provision. There is a clear trend to use electronic contracts between service consumers and one or more service providers, in order to achieve the necessary reliability and commitment from all parties. Service Level Agreements (SLAs) are the means to model and manage such contracts in a unified way. Grids and Service-Oriented Architectures for Service Level Agreements, the thirteenth volume of the CoreGRID series, contains current research and up-to date solutions from research and business communities presented at the IEEE Grid 2009 Workshop on Service Level Agreements in Grids, and the Service Level Agreements in Grids Dagstuhl Seminar 2009. The contributions in this volume cover Grid environments, but also generic models for SLA management that are applicable to service-oriented systems in general, like market-economic strategies, negotiation models, or monitoring infrastructures. Grids and Service-Oriented Architectures for Service Level Agreements is designed for a professional audience composed of researchers and practitioners within the Grid community industry, and is also suitable for advanced-level students in computer science."],["dc.identifier.doi","10.1007/978-1-4419-7320-7"],["dc.identifier.eisbn","978-1-4419-7320-7"],["dc.identifier.isbn","978-1-4419-7319-1"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/15366"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.title","Grids and Service-Oriented Architectures for Service Level Agreements"],["dc.type","book"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.lastpage","4"],["dc.contributor.author","Azodolmolky, Siamak"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2019-02-12T09:12:12Z"],["dc.date.available","2019-02-12T09:12:12Z"],["dc.date.issued","2014"],["dc.description.abstract","Delivering scalable packet-switched interconnects that can support the bursty Ethernet traffic, which is common in many data centre applications is a challenging problem that is only getting harder. Implementing the control logic capable of deciding how to forward each packet individually in current packet-switched Ethernet interconnects is not optimized and researchers are proposing hybrid optical/electronic Top of Rack (ToR) architectures to improve the performance towards an optimized operation. Emerging applications (e.g, Big Data) and potential cross-layer performance improvement is another interesting topic that should be properly addressed in future data centres. In this paper a summary of recent developments of optical networking in data centres will be presented. Our software-defined optical network emulation platform is introduced and initial WDM link modelling as a tool for cross layer investigation and optimization are presented. A nonlinear optical signal propagation tool (as a network application) and related results are presented."],["dc.identifier.doi","10.1109/ICTON.2014.6876286"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57550"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.conference","16th International Conference on Transparent Optical Networks (ICTON)"],["dc.relation.eventend","2014-07-10"],["dc.relation.eventlocation","Graz, Austria"],["dc.relation.eventstart","2014-07-06"],["dc.relation.isbn","978-1-4799-5601-2"],["dc.relation.ispartof","16th International Conference on Transparent Optical Networks (ICTON)"],["dc.title","The impact of software-defined optical networks on data centre optimization"],["dc.type","conference_paper"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","930"],["dc.bibliographiccitation.lastpage","933"],["dc.contributor.author","Jehangiri, Ali Imran"],["dc.contributor.author","Yahyapour, Ramin"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yaqub, Edwin"],["dc.contributor.author","Lu, Kuan"],["dc.date.accessioned","2019-02-13T07:30:14Z"],["dc.date.available","2019-02-13T07:30:14Z"],["dc.date.issued","2014"],["dc.description.abstract","Virtualized Cloud platforms have become increasingly common and the number of online services hosted on these platforms is also increasing rapidly. A key problem faced by providers in managing these services is detecting the performance anomalies and adjusting resources accordingly. As online services generate a very large amount of monitored data in the form of time series, it becomes very difficult to process this complex data by traditional approaches. In this work, we present a novel distributed parallel approach for performance anomaly detection. We build upon Holt-Winters forecasting for automatic aberrant behavior detection in time series. First, we extend the technique to work with MapReduce paradigm. Next, we correlate the anomalous metrics with the target Service Level Objective (SLO) in order to locate the suspicious metrics. We implemented and evaluated our approach on a production Cloud encompassing IaaS and PaaS service models. Experimental results confirm that our approach is efficient and effective in capturing the metrics causing performance anomalies in large time series datasets."],["dc.identifier.doi","10.1109/CLOUD.2014.129"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57552"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.conference","IEEE 7th International Conference on Cloud Computing"],["dc.relation.eventend","2014-07-02"],["dc.relation.eventlocation","Anchorage, AK, USA"],["dc.relation.eventstart","2014-06-27"],["dc.relation.isbn","978-1-4799-5063-8"],["dc.relation.isbn","978-1-4799-5062-1"],["dc.relation.ispartof","IEEE 7th International Conference on Cloud Computing"],["dc.relation.orgunit","Gesellschaft für wissenschaftliche Datenverarbeitung"],["dc.title","Diagnosing Cloud Performance Anomalies Using Large Time Series Dataset Analysis"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.lastpage","6"],["dc.contributor.author","Fatemi Moghaddam, Faraz"],["dc.contributor.author","Wieder, Philipp"],["dc.contributor.author","Yahyapour, Ramin"],["dc.date.accessioned","2019-02-06T10:55:46Z"],["dc.date.available","2019-02-06T10:55:46Z"],["dc.date.issued","2017"],["dc.description.abstract","Despite the considerable benefits of cloud computing as an emerging technology, there are some reliability and privacy concerns such as generating and managing access policies according to sensitivity of stored data in cloud storages. The most challenging issue in current information policy models is managing security levels, mapping between access requests and defined policies and considering the flexibility and scalability of this management schema according to the characteristics of cloud computing models. Accordingly, an efficient token-based access model has been presented in this paper to provide a semantic mapping between access requests of cloud users and defined policies and sub-policies of cloud customers according to the authentication and access management protocols of protection ontology. Furthermore, a policy-based session token has been introduced to enhance the reliability of access, decrease the time of mapping by eliminating un-necessary mapping from checked policies and decrease data overhead of by classification of policies and sub-policies."],["dc.identifier.doi","10.1109/CCST.2017.8167836"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57528"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation.conference","International Carnahan Conference on Security Technology (ICCST)"],["dc.relation.eventend","2017-10-26"],["dc.relation.eventlocation","Madrid, Spain"],["dc.relation.eventstart","2017-10-23"],["dc.relation.isbn","978-1-5386-1585-0"],["dc.relation.ispartof","2017 International Carnahan Conference on Security Technology (ICCST)"],["dc.relation.orgunit","Gesellschaft für wissenschaftliche Datenverarbeitung"],["dc.title","Token-based policy management (TBPM): A reliable data classification and access management schema in clouds"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]