In Wireshark I have TCP conversation with iRTT of 55ms, but I noticed in Wireshark that ACK RTT time is increasing constantly, starting from 60ms (without SYN ACK packet in which I see iRTT of 55ms) and going up to around 785ms before Windows Full packet is received.
Why is this happening? Is this normal condition in which receiver need to process the packet and that's why increasing the ACK's time or this is something else...?
P.S. Conversation is about uploading a file from my computer to Dropbox server, which means that Dropbox is receiver who send ACK's with constantly increasing time.
P.P.S. I've noticed that Delayed ACK's are used on every second packet.