This preview shows page 1. Sign up to view the full content.
Unformatted text preview: he events performed by the client stub are as follows: time 0: send request 1; time 4:
time out and retransmit request 1; time 5: receive server's reply 1, return reply to
application; time 5: send request 2; time 9: time out and retransmit request 2; time 10:
receive server's reply 1, but ignore it since we're waiting for reply 2; time II: receive
server's reply 2, return reply to application.
The events at the server are as follows: time 0: receive request 1, start operation; time 5:
send reply 1; time 5: receive request 1 (from client's retransmission at time 4), start
operation; time 10: send reply 1; time 10: receive request 2 (from client's transmission at
tune 5), start operation; time II: send reply 2; time II: receive request 2 (from client's
retransmission at time 9), start operation; time 12: send reply 2. This final server reply is
just queued by the client's UDP for the next receive done by the client. When the client
reads it, the XID will be wrong, and the client will ignore it.
29.4 Changing the server's Ethernet card changes its physical address. Even though we
noted in Section 4.7 that SVR4 does not send a gratuitous ARP on bootstrap, it still must
send an ARP request for the physical address of sun before it can reply to its NFS
requests. Since sun already has an ARP entry for svr4, it updates this entry with the
sender's (new) hardware address from the ARP request.
29.5 The second of the client's block I/O daemons (reading at offset 73728) is out of sync
with the first by about 0.74 seconds. That is, this second daemon times out 0.74 seconds
after the first in lines 131-145. It appears the server never saw the request in line 167, but
did see the request in line 168. The second block I/O daemon won't retransmit until 0.74
seconds after line 168, and in the mean time the first block I/O daemon continues issuing
requests. file:///D|/Documents%20and%20Settings/bigini/Doc...omenet2run/tcpip/tcp-ip-illustrated/append_d.htm (19 of 20) [12/09/2001 14.48.04] Appendix D: Solutions to Selected Exercises 29.6 If TCP is used, and the TCP segment containing the server's reply is l...
View Full Document
This test prep was uploaded on 04/04/2014 for the course ECE EL5373 taught by Professor Guoyang during the Spring '12 term at NYU Poly.
- Spring '12