Kathleen S. Meier-Hellstern

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Methodology is presented for analyzing a queueing submodel which frequently arises in the study of overflow models-a finite capacity, multiserver queue with exponentially distributed service times, and arriving traffic consisting of a Poisson parcel and several overflow parcels. By modeling the overflow parcels as interrupted Poisson processes, an exact(More)
The Domain Name System (DNS) is an essential network infrastructure component since it supports the operation of the Web, Email, Voice over IP (VoIP) and other businesscritical applications running over the network. Events that compromise the security of DNS can have a significant impact on the Internet since they can affect its availability and its(More)
Mobile computing is a new emerging computing paradigm posing many challenging data management problems. We identify these new challenges and investigate their technical signi cance. New research problems include management of location dependent data, information services to mobile users, frequent disconnections, wireless data broadcasting, and energy e(More)
In the most general case there could be multiple servers and multiple clients moving in and out of the respective home location areas. This requires a hierarchical replication scheme where cumulative read/write activity of clients and servers have to be taken under consideration. Dynamic replication schemes of [8] can be extended here to handle mobility.(More)
IP application performance must frequently be assessed using empirical methods that combine performance testing and modeling. We have developed an approach to identifying bottlenecks using performance signatures. A performance signature is a set of characteristic and repeatable behaviors (e.g., response time, resource utilization or throughput vs. some(More)