Tcp AIMD

Question

Consider  "Additive -increase multiplicative -decrease "approach of TCP congestion control.one MSS(Maximum Segment Size)is 512B .If the TCP sender doesn't perceive the path as not congested then. What will be the congestion window size after 4RTTS provided the congestion window is assigned 1MSS initially ?

Answer 1

After 1st RTT -> (512x2) = 1024 Bytes

After 2nd RTT -> (512x3)  = 1536 Bytes

After 3rd RTT -> (512x4) = 2048 Bytes

After 4th RTT - > (512x5) = 2560 Bytes

Comments

prashant jha 1

But here why not  send  the MSS in exponential manner

i:e     1 | 2 |  4| 8 |16....... ????

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Because it is additivea increase , not exponential increase , no where it is written that the system is in slow start phase

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In Slow start phase for each RTT the window size increases exponentially , that is exponential increase . It is given that system is using Additive increase , so it can be assumed that the system is using congestion avoidance technique and not slow start.

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Ohk ohk Thanks I didn't know that concept  of AIMD

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source of this concept????////