in Computer Networks
4,169 views
1 vote
1 vote

True or false?

  1. Host A is sending Host B a large file over a TCP connection. Assume Host B has no data to send Host A. Host B will not send acknowledgments to Host A because Host B cannot piggyback the acknowledgments on data.
  2. The size of the TCP rwnd never changes throughout the duration of the connection.

  1. Suppose Host A is sending Host B a large file over a TCP connection. The number of unacknowledged bytes that A sends cannot exceed the size of the receive buffer. 
  1. Suppose Host A is sending a large file to Host B over a TCP connection. If the sequence number for a segment of this connection is m, then the sequence number for the subsequent segment will necessarily be m + 1.
  1. The TCP segment has a field in its header for rwnd.
  2.  Suppose that the last SampleRTT in a TCP connection is equal to 1 sec. The current value of the TimeoutInterval for the connection will necessarily be  $\gt = $ 1 sec.
  3.  Suppose Host A sends one segment with sequence number 38 and 4 bytes of data over a TCP connection to Host B. In this same segment the acknowledgment number is necessarily 42.
in Computer Networks
4.2k views

1 Answer

1 vote
1 vote

(A.) False. B can send the acknowledgement alone.

(B.) False. Rwnd may change during connection. Although Reciever Buffer remain fixed.

(C.) True. Since the number of unacknowledged bytes that A sends cannot exceed the size of the receive window.  So there will be no way it can exceed reciever buffer, since rwnd <= rcvr buffer.

(D.)False. It is not necessary. Let say sender sends following segment with seq. number 10-19 it gets received , 20-29 gets lost ,30-39 get rcvd, now sender can retransmit segment (20-29) instead of (40-49).

(E) True. Header contains field window size(advertised window) of 16 bit

(G.) False. it may be the case that the segment sent before the segment with sequence number (38-41) got lost. then the acknowledgement number will not be 42.

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

edited by

1 comment

a- false

b- false

c- true

d- false

e- true

f- false    as RTO should be greater than the RTT

g- false
0
0

Related questions