TCP Slow start window size

Question

I am revising for a networks exam and I am not sure of the answer to the following:

Consider the effect of using slow-start on a link with a 10ms round-trip time
and no congestion. The receive window is 24KB and the maximum segment
size is 2KB. How long does it take before the first full window can be sent
in one transmission round?

after every ACK, does the max segment size grow by 1 or does it double? If it doubles, would the answer be 50ms because 2KB^5 = 32KB so after 5 trips the MSS will equal 32KB and due to 10ms round-trip time it will be 10x5 = 50ms?

Answer 1

I found a solution to your question here (Problem 4):

http://web.eecs.utk.edu/~qi/teaching/ece453f06/hw/hw7_sol.htm

You are more or less correct, except you disregard the last RTT (since the window size goes beyond 24KB). So your answer is:

4 x 10 = 40ms.