triple duplicate acknowledgement in TCP congestion control

Posted by Salvador Dali on Server Fault See other posts from Server Fault or by Salvador Dali
Published on 2012-10-27T16:41:49Z Indexed on 2012/10/27 17:02 UTC
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Filed under:

networking

|

tcp

If this doesn't belong here, please tell me where is an appropriate place for such question.

I am trying to understand ideas behind tcp congestion control mechanisms, and I am failing to understand why we need triple duplicate acknowledgement to trigger window change.

In my opinion, double duplicate acknowledgement will be enough to get that the previous package is lost. So why we need the third ack?

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