Sachin Agarwal

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Of considerable interest in recent years has been the problem of exchanging correlated data with minimum communication. We thus consider the problem of exchanging two similar strings held by different hosts. Our approach involves transforming a string into a multiset of substrings that are reconciled efficiently using known multiset reconciliation(More)
The rapid advent of “Web 2.0” applications has unleashed new HTTP traffic patterns which differ from the conventional HTTP request-response model. In particular, asynchronous pre-fetching of data in order to provide a smooth web browsing experience and richer HTTP payloads (e.g., Javascript libraries) of Web 2.0 applications induce larger, heavier, and more(More)
We evaluate the performance of a large-scale live P2P video multicast session comprising more than 120, 000 peers on the Internet. Our analysis highlights P2P video multicast characteristics such as high bandwidth requirements, high peer churn, low peer persistence in the P2P multicast system, significant variance in the media stream quality delivered to(More)
The erasure resilience of rateless codes, such as Luby-Transform (LT) codes, makes them particularly suitable to a wide variety of loss-prone wireless and sensor network applications, ranging from digital video broadcast to software updates. Yet, traditional rateless codes usually make no use of a feedback communication channel, a feature available in many(More)
Modern Personal Digital Assistant (PDA) architectures often utilize a wholesale data transfer protocol known as “slow sync” for synchronizing PDAs with Personal Computers (PCs). This approach is markedly inefficient with respect to bandwidth usage, latency, and energy consumption, since the PDA and PC typically share many common records. We propose,(More)
Modern Personal Digital Assistant (PDA) architectures often utilize a wholesale data transfer protocol known as “slow sync” for synchronizing PDAs with Personal Computers (PCs). This approach is markedly inefficient with respect to bandwidth usage and latency, since the PDA and PC typically share many common records. We propose, analyze, and implement a(More)
We evaluate and compare the performance of three P2P streaming systems that are capable of streaming live video on the Internet by testing them on a carefully controlled, traffic-shaped network test-bed. We first describe the construction of the test-bed based upon Internet measurements between geographically distributed hosts. Then, we present a(More)
This paper presents the prototype of an expert peering system for information exchange in the knowledge society. Our system realizes an intelligent, real-time search engine for enterprise Intranets or online communities that automatically relays user queries to knowledgable specialists. According to its very nature, the system requires a sound integration(More)
This paper proposes a novel expert peering system for information exchange. Our objective is to develop a real-time search engine for an online community where users can query experts, who are simply other participating users knowledgeable in that area, for help on various topics. We consider a graph-based scheme consisting of an ontology tree where each(More)
In this paper we present the design, implementation, and evaluation of Jiminy: a framework for explicitly rewarding users who participate in reputation management systems by submitting ratings. To defend against participants who submit random or malicious ratings in order to accumulate rewards, Jiminy facilitates a probabilistic mechanism to detect(More)