Consider three IP networks A, B and C. Host HA in network A sends messages each containing 180 bytes of application data to a host HC in network C. The TCP layer prefixes a 20 byte header to the message. This passes through an intermediate network B. The maximum packet size, including 20 byte IP header, in each network is
A : 1000 bytes
B : 100 bytes
C : 1000 bytes
The network A and B are connected through a 1 Mbps link, while B and C are connected by a 512 Kbps link (bps = bits per second).
What is the rate at which application data is transferred to host HC? Ignore errors, acknowledgements, and other overheads.
(A) 325.5 Kbps
(B) 354.5 Kbps
(C) 409.6 Kbps
(D) 512.0 Kbps
Answer: (B)
Explanation:
Host C receives 260 bytes of data (including headers) out of which 180 bytes is of application data. Thus the efficiency is 180/260 = 0.6923.
Thus the rate at which application data is transferred to host C would be 0.6923 * 512 Kbps = 354.45 Kbps.
( How host C receives 260 bytes of data is shown here: https://www.geeksforgeeks.org/gate-gate-cs-2004-question-56/amp/