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Consider an instance of TCP’s Additive Increase Multiplicative Decrease (AIMD) algorithm where the window size at the start of slow start phase is 2 MSS and the threshold at the start is 1st transmission is 16 MSS. Assume TCP use over a lossy link i.e., timeout occur after transmission of 7th packet . The congestion window size at the end of 14 RTT is _________ (in MSS).
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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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here TOTAL 2000 segments need to be sent, and after x RTT, it will send 2001 segments but for total we shall take count of addition of all the previous also na?