0 votes 0 votes Consider instance of TCP AIMD protocol where the Window size at start is cwnd = 2, and the threshold is ssthresh = 16. Timeout occurs during the transmission of 7th packet. What is the value of cwnd at the end of 14RTT ? Computer Networks congestion-control algorithms computer-networks + – Na462 asked Sep 20, 2018 Na462 1.0k views answer comment Share Follow See all 6 Comments See all 6 6 Comments reply Show 3 previous comments Na462 commented Sep 25, 2018 reply Follow Share PLEASE POINT MY MISTAKE :) 0 votes 0 votes nephron commented Sep 25, 2018 reply Follow Share see the answer. 0 votes 0 votes Magma commented Sep 25, 2018 reply Follow Share Na462 can you tell me that what's the answer given ??? 0 votes 0 votes Please log in or register to add a comment.
1 votes 1 votes this is the seq: trans started -> cwind 1 -> 2 2 ->4 3 ->8 4->16 5->17 6->18 7->19 new ssthresh = 9.5 => 9 new cwind = 1 8 -> 1 9->2 10->4 11->8 12->9 13->10 14->11 (14th transmission has started at cwind =11) so when 14th transmission has ended we have 14RTT and cwind increased from 11 to 12 nephron answered Sep 24, 2018 • edited Sep 24, 2018 by nephron nephron comment Share Follow See all 10 Comments See all 10 10 Comments reply nephron commented Sep 25, 2018 reply Follow Share I didnot get u. It simply mentions timeout occurs during transmission of 7th packet. It does not mention every 7th packet 0 votes 0 votes Magma commented Sep 25, 2018 reply Follow Share ans is 13 bro here it's given that Window size at start is cwnd = 2 therefore, slow start is start with 2 mss not 1 mss 0 votes 0 votes nephron commented Sep 25, 2018 i edited by nephron Sep 25, 2018 reply Follow Share Sorry, this not about slow start and CA. It is about timeout. In case of loss due to timeout cwind = 1MSS. 0 votes 0 votes Magma commented Sep 25, 2018 reply Follow Share cwnd = 2 means it start with 2 segment 2 4 8 ...... that's how series is executed 0 votes 0 votes nephron commented Sep 25, 2018 reply Follow Share it start with 2, 4, 8 but after timeout it starts with 1, 2, 4, 8... 0 votes 0 votes Magma commented Sep 25, 2018 reply Follow Share no , after timeout again it starts with 2 ,4 ,8 0 votes 0 votes nephron commented Sep 25, 2018 reply Follow Share please mention the source ???? .... i hv read it starts from 1,2,4 0 votes 0 votes Smishra95 commented Sep 25, 2018 i edited by Smishra95 Sep 25, 2018 reply Follow Share source :- Forouzan >>>when there Time out occurs then TCP acts strongly : A:- It sets the valuee of threshold to one half the current window size. B:- it sets cwnd the size of one segment . C: it strats slow -start phase again. >>> when detection is by ACK's i.e. three ACK's received then : A:- - It sets the valuee of threshold to one half the current window size. B: sets CWND to threshold. C: congestion avoidance phase starts. In This question starting window size is two . That's why it must be two , four, eight ... 0 votes 0 votes nephron commented Sep 25, 2018 reply Follow Share Answer in the above Forozoun is B ?? isn't it B option mentions that cwind = 1 segment so it is repeating from 1,2, 4... after timeout 0 votes 0 votes Magma commented Sep 25, 2018 reply Follow Share nephron Hmm I was wrong...thank you 0 votes 0 votes Please log in or register to add a comment.