The design of an end-to-end Internet congestion control protocol that could achieve high utilization, fair sharing of bottleneck bandwidth, and fast convergence while remaining TCP-friendly is an ongoing challenge that continues to attract considerable research attention. This paper presents ACP, an Adaptive end-to-end Congestion control Protocol that achieves the above goals in high bandwidth-delay product networks where TCP becomes inefficient. The main contribution of ACP is a new form of congestion window control, combining the estimation of the bottleneck queue size and a measure of fair sharing. Specifically, upon detecting congestion, ACP decreases the congestion window size by the exact amount required to empty the bottleneck queue while maintaining high utilization, while the increases of the congestion window are based on a “fairness ratio” metric of each flow, which ensures fast convergence to a fair equilibrium. We demonstrate the benefits of ACP using both ns-2 simulation and experimental measurements of a Linux prototype implementation. In particular, we show that the new protocol is TCP-friendly and allows TCP and ACP flows to coexist in various circumstances, and that ACP indeed behaves more fairly than other TCP variants under heterogeneous round-trip times (RTT).

This paper focuses on large graph processing based on the remote memory system. Using our remote memory system enables applications to deal with large data sets, especially graph data, which do not fit into the machines main memory. Although recent dramatic increases in DRAM capacity now allow us to build inexpensive computers with very large amounts of main memory, the rise in brand-new Internet services has resulted in rapid increases in data size. This is especially true for on-line social network services that generate various data sets that can be represented as graphs. On the other hand, high-speed networking technologies such as Infini Band, Myrinet and 10G Ethernet now enable us to transfer data with low latency and high throughput. The advanced networking technologies reduce the latency/bandwidth gap between main memory and remote memory. Thus, remote memory based processing could now be helpful in accelerating large-scale graph process when main memory space is insufficient to store application data. In this paper, we present our design and implementation of remote memory system that efficiently processes large graph data. We also evaluate a breadth-first search of various types of graphs using our system and show that our approach is good for large graph data processing.

Recently, REpresentational State Transfer (REST) has been proposed as an alternative architecture for Web services.In the era of Cloud and Web 2.0, many complex Web service-based systems such as e-Business an de-Government applications have adopted REST. Unfortunately, the REST approach has been applied to few cases in management systems, especially for a management system for cloud computing infrastructures.In this paper, we design and implement a RESTful Cloud Management System (CMS).Managed elements can be modeled as resources in REST and operations in existing systems can be evaluated using four methods of REST or a combination of them.We also show how components of existing management systems can be realized as REST-style Web services.

Item matchmaking that finds items for users is an essential service framework in the web service infrastructure. The current way of carrying out the matchmaking procedure is the selection of items based on a user's specifications. We rethink the item matchmaking framework in such a way that a matchmaker can find items that can satisfy a specific computing demand from a user and recommend a collection of better items candidates among the identified items. This endows a user with the right of choice on deciding best-possible items. We approach the problem in the view of skyline query processing that has become one of the major topics in the database community, and present the efficient skyline algorithm that gathers interesting item candidates efficiently. To this end, we adopt (i) lattice-based indexing using a lattice composition technique,and (ii) an optimized dominance-check algorithm. Our extensive experimental results show that our algorithm outperforms the current state-of-the-art algorithm.

MapReduce is Google's programming model for easy development of scalable parallel applications which process huge quantity of data on many clusters. Due to its conveniency and efficiency, MapReduce is used in various applications (e.g., Web search services and online analytical processing). However, there are only few good benchmarks to evaluate MapReduce implementations by realistic testsets. In this paper, we present MRBench that is a benchmark for evaluating MapReduce systems. MRBench focuses on processing business oriented queries and concurrent data modifications. To this end, we build MRBench to deal with large volumes of relational data and execute highly complex queries. By MRBench, users can evaluate the performance of MapReduce systems while varying environmental parameters such as data size and the number of (map/reduce) tasks. Our extensive experimental results show that MRBench is a useful tool to benchmark the capability of answering critical business questions.