Large-scale virtualized data centers require cloud providers to implement scalable, autonomic, and energy-efficient cloud management systems. To address these challenges this thesis provides four main contributions. The first one proposes Snooze, a novel Infrastructure-as-a-Service (IaaS) cloud management system, which is designed to scale across many thousands of servers and virtual machines (...

An impressive amount of work has been done to date on improving the electrical efficiency of various data center components. The data storage industry has begun to see the fruits of this effort, with increased power supply and fan efficiencies. However, storage presents other significant opportunities for energy conservation, through various types of capacity optimization, that are not captured...

The SDN control plane needs to frequently update the data plane as the network conditions change. Since each switch updates its flow table independently and asynchronously, the transition of data plane state—if done directly from the initial to the final stage—may result in serious flash congestion. Prior work strives to find a congestion-free update plan with multiple stages, each with the pro...

Internet data centers (IDCs) perform multi-customer hosting on a virtual-ized collection of hardware resources. These systems give a new answer to website hosting by delegating all the worry of server management on the IDC provider side. These computing farms have to cope with important issues. Besides management and security considerations we find the important problem of resource allocations....

A fundamental challenge in data centers is how to design distinguished networking topology for efficiently interconnecting a large number of servers. This paper studies the design of Data Center Networking (DCN) from the aspect of the degree/diameter problem, which determines desirable DCNs that support the largest number of servers given maximum server degree and given diameter. More specifica...

Data centers are large energy consumers today and their consumption is expected to increase further, driven by the growth in cloud services. The large costs and the environmental impact of this consumption have motivated data center operators to optimize data center operations. We argue that one of the underlying reasons for the low energy utilization is the lack of visibility into a data cente...

Management of computing infrastructure in data centers is an important and challenging problem, that needs to: i) ensure availability of services conforming to the Service Level Agreements (SLAs); and ii) reduce the Power Usage Efficiency (PUE), i.e. the ratio of total power, up to half of which is attributed to data center cooling, over the computing power to service the workloads. The cooling...

NetFlow has been a widely used monitoring tool with a variety of applications. NetFlow maintains an active working set of flows in a hash table that supports flow insertion, collision resolution, and flow removing. This is hard to implement in merchant silicon at data center switches, which has limited per-packet processing time. Therefore, many NetFlow implementations and other monitoring solu...

Most networked applications use either a largely centralized architecture (e.g. iTunes) or a p2p architecture (e.g. BitTorrent). The popularity of centralized Internet applications such as Search and web portals has fueled the growth of large data centers. Modeling and minimizing the power consumption of large data centers is the hot new research area (pun intended). However, no attention has b...