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Several recent studies have proposed methods to accelerate the receipt of a file by downloading its parts from different servers in parallel. This paper formulates models for an approach based on receiving only one copy of each of the data packets in a file, while different packets may be obtained from different sources. This approach guarantees faster downloads with lower network use. However, out-of-order arrivals at the receiving side are unavoidable. We present methods to keep out-of-order low to insure more regulated flow of packets to the application. Recent papers indicate that out-of-order arrivals have many unfavorable consequences. A good indicator to the severeness of out-of-order arrival is the resequencing-buffer occupancy. The paper focuses on the analysis of the resequencing-buffer occupancy distribution and on the analysis of the methods used to reduce the occupancy of the buffer.

We consider the problem of achievable per-node throughput in an extended distributed wireless network where the node locations are random and the channel attenuation between pairs of nodes exhibits independent random multipath fading.In [1] a clever protocol construction based on percolation theory was used to show that a per-node throughput of a constant times 1 √ n bits per second is achievable with probability approaching one as the expected number of nodes in the network, n, becomes large (i.e. w.h.p.), for networks with random node locations under a deterministic channel gain modeling path-loss and absorption.We use a similar approach to extend the result to a more realistic channel gain model where the channel gains are random due to multipath effects. In particular, we show that a constant times 1 √ n bps node is also achievable, w.h.p., when the channel gains are random. The result applies to independent, frequency flat fading channel models where the tail probability exhibits an exponential decay (e.g., any mixture of line of sight and Rayleigh, Rice and Nakagami distributions).

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