Slow start phase starts with 2 MSS
Threshold = 16 MSS
2 (1ST RTT)
4 (2ND RTT)
8 (3RD RTT)
16 (4TH RTT) Threshold reached Start congestion avoidance
17 (5TH RTT)
18 (6TH RTT)
19 (7TH RTT) Timeout occurs at the end of 7th transmission So when 19 Segments are sent , TO timer expired Before 7th RTT. Should we include time after 7th transmission Actually I think yes anyway next transmission starts after TO which is less that 7th RTT. As we don't have idea about Timeout we include it as RTT
New threshold = 19/2 = 9.5 = 9 , Start slow start phase again With 1 MSS. We can start with 2 MSS as well
check this out here marks given to all for such ambiguity. https://gateoverflow.in/2156/gate2012-45
1 (8TH RTT)
2 (9TH RTT)
4 (10TH RTT)
8 (11TH RTT)
9 (12TH RTT)
10 (13TH RTT)
11 (14TH RTT)
12 ...........
So at the end of 14th RTT window is 12 MSS
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