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This paper introduces Time-lined TCP (TLTCP). TLTCP is a protocol designed to provide TCP-friendly delivery of time-sensitive data to applications that are loss-tolerant, such as streaming media players. Previous work on unicast delivery of streaming media over the Internet proposes using UDP and performs congestion control at the user level by regulating(More)
We consider the problem of providing vehicular Internet access using roadside 802.11 access points. We build on previous work in this area [18, 8, 5, 11] with an extensive experimental analysis of protocol operation at a level of detail not previously explored. We report on data gathered with four capture devices from nearly 50 experimental runs conducted(More)
We study the problem of processor scheduling for n parallel jobs applying the method of competitive analysis. We prove that for jobs with a single phase of parallelism, a preemptive scheduling algorithm without information about job execution time can achieve a mean completion time within 2 − 2 n+1 times the optimum. In other words, we prove a competitive(More)
A multiprocessor system is unlikely to have access to information about the execution characteristics of the jobs it is to schedule. In this work, we are interested in scheduling algorithms for batch jobs that require no such knowledge (such algorithms are called non-clairvoyant). Preemptive scheduling (i.e., redistribution of processors) is important to(More)
When a roadside 802.11-based wireless access point is shared by more than one vehicle, the vehicle with the lowest transmission rate reduces the effective transmission rate of all other vehicles. This <i>performance anomaly</i> [9] degrades both individual and overall throughput in such multi-vehicular environments. Observing that every vehicle eventually(More)
A multiprocessor system is unlikely to have access to information about the execution characteristics of the jobs it is to schedule. In this work, we are interested in scheduling algorithms for batch jobs that require no such knowledge (such algorithms are called non-clairvoyant). Preemptive scheduling (i.e., redistribution of processors) is important to(More)
In this paper, we describe the design of a system, called ParaWeb, for utilizing Internet or intra-net computing resources in a seamless fashion. The goal is to allow users to execute serial programs on faster compute servers or parallel programs on a variety of possibly heterogeneous hosts. ParaWeb provides extensions to the Java programming environment(More)
Large-scale Non-Uniform Memory Access (NUMA) multiprocessors are gaining increased attention due to their potential for achieving high performance through the replication of relatively simple components. Because of the complexity of such systems, scheduling algorithms for parallel applications are crucial in realizing the performance potential of these(More)
In systems that support garbage collection, a tension exists between collecting garbage too frequently and not collecting it frequently enough. Garbage collection that occurs too frequently may introduce unnecessary overheads at the risk of not collecting much garbage during each cycle. On the other hand, collecting garbage too infrequently can result in(More)
In multiprocessors a parallel program's execution time is directly innuenced by the number of processors it is allocated. The problem of scheduling parallel programs in a multiprogrammed environment becomes one of determining how to best allocate processors to the diierent simultaneously executing programs in order to minimize mean response time. In this(More)