7 votes 7 votes Consider TCP congestion control. Assuming RTT as 4 seconds and segment size as 3KB, if bandwidth is 500kbps, what is the smallest window size for which there is no stalling in this case? Computer Networks computer-networks tcp + – rahul sharma 5 asked Aug 16, 2017 rahul sharma 5 1.6k views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply joshi_nitish commented Aug 16, 2017 reply Follow Share 252KB ?? 0 votes 0 votes sourav. commented Aug 16, 2017 reply Follow Share $651KB$? 0 votes 0 votes Please log in or register to add a comment.
4 votes 4 votes Given Data Bandwidth = 500 Kbps Segment size = 3KB Round Trip Time = 4 sec So window size will depend upon the data we can send in 1 RTT i.e in 4 sec To send 500 Kb we need 1 sec In 4 sec we can send = 500 x 4 kb Given segment size = 3 KB Therefore number of such segments we can send in 4 sec = $\frac{500 \times 4 k}{3 \times 2^{3} k}$ So in 4 sec we can send $\left \lfloor 83.33 \right \rfloor = 83$ segments Therefore smallest window size should be 83 stblue answered Aug 16, 2017 stblue comment Share Follow See all 9 Comments See all 9 9 Comments reply Show 6 previous comments rahul sharma 5 commented Aug 18, 2017 reply Follow Share Maximum window size is always number of frames in RTT+1 always. Refer tanenbaum Sec 3.4 p 233 it explained this thing beautifully 1 votes 1 votes Rajesh Panwar commented Jan 14, 2019 reply Follow Share i don't think this one is correct solution 0 votes 0 votes sachin486 commented Dec 29, 2021 reply Follow Share in Gate please be carefull to take 5Kb as 5000kb and 3KB data as 3 x 8 x 1024 bits so that u can get correct answer that is 83 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes i think window size:- 85 segments ???? ... if not ,please explain.... hs_yadav answered Aug 16, 2017 hs_yadav comment Share Follow See 1 comment See all 1 1 comment reply Rajesh Panwar commented Jan 14, 2019 reply Follow Share could you explain? 0 votes 0 votes Please log in or register to add a comment.