And finally, upon receipt of message 2, the destination can now send back one final ack indicating that it received all three messages for this sequence.

并且最后，一收到Message 2，目的地就可以发送回最终的ACK来标志它收到了这个队列中的所有三个消息。

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The director's other movies included Final Destination 2, 2009's The Final Destination and 2011's Shark Night 3D.

BBC: David R Ellis, director of Snakes on a Plane, dies