UNCHOKER (u=36Mbps) 3 11 182095 PEERS UNCHOKER (u=36Mbps) Recall the tit-for-tat incentive mechanism used by BitTorrent....

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UNCHOKER (u=36Mbps) 3 11 182095 PEERS UNCHOKER (u=36Mbps) Recall the tit-for-tat incentive mechanism used by BitTorrent. Assume that an unchoker's overall upload datarate is 36Mbps. Consider the volumes of traffic uploaded from peers to an unchoker as indicated in Round t of the diagram below: Round t Round t+1 Round t+2 PEERS 28* *These numbers indicate a peer's upload speed in Mbps. Assume that a peer's upload speed remains the same across all rounds. a. Which peers will be selected for subsequent upload from the unchoker in Round t+1? At what datarates will the unchoker upload to these peers? Indicate your answer as arrows and numbers on the diagram above. b. If peer 8 (the one with upload speed of 28Mbps) was to launch a Sybil attack on the unchoker in Round t+2, how many streams will peer 8 get? Justify your answer. UNCHOKER (u=36Mbps) PEERS UNCHOKER (u=36Mbps) 3 11 182095 PEERS UNCHOKER (u=36Mbps) Recall the tit-for-tat incentive mechanism used by BitTorrent. Assume that an unchoker's overall upload datarate is 36Mbps. Consider the volumes of traffic uploaded from peers to an unchoker as indicated in Round t of the diagram below: Round t Round t+1 Round t+2 PEERS 28* *These numbers indicate a peer's upload speed in Mbps. Assume that a peer's upload speed remains the same across all rounds. a. Which peers will be selected for subsequent upload from the unchoker in Round t+1? At what datarates will the unchoker upload to these peers? Indicate your answer as arrows and numbers on the diagram above. b. If peer 8 (the one with upload speed of 28Mbps) was to launch a Sybil attack on the unchoker in Round t+2, how many streams will peer 8 get? Justify your answer. UNCHOKER (u=36Mbps) PEERS