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A diagram depicting the SOS architecture is show in Figure J-3above. SOS works by redirecting the designated TCP connection of such a long distance data transfer to a local SOS agent via an in-path OpenFlow switch. The local SOS agent transparently acknowledges the packets from the source of the data transfer as if it was the intended destination. Because the local SOS agent is deployed on the source’s local network, the delay-to-acknowledgement is negligible as compared to the real destination. As such, the source can continuously transfer data to the local agent without pause.
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