EBK COMPUTER NETWORKING
7th Edition
ISBN: 8220102955479
Author: Ross
Publisher: PEARSON
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Chapter 8, Problem R30RQ
Program Plan Intro
Stateful Packet Filters:
Stateful Packet Filters are dynamic packet filtering and is a firewall technology that monitors the state of active connections.
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5. Expand the information on the Transmission Control Protocol for this packet in
the Wireshark “Details of selected packet” window (see Figure 3 in the lab
writeup) so you can see the fields in the TCP segment carrying the HTTP
message. What is the destination port number (the number following “Dest Port:”
for the TCP segment containing the HTTP request) to which this HTTP request is
being sent?
SMTP (Simple Mail Transfer Protocol) is the standard protocol for transferring mail
between hosts over Transmission Control Protocol (TCP). A TCP connection is set up
between a user agent and a server program. The server listens on TCP port 25 for
incoming connection requests. The user end of the connection is on a TCP port number
above 1023. Suppose you wish to build a packet filter rule set allowing inbound and
outbound SMTP traffic. You generate the following rule set:
Rule Direction Src Addr Dest Addr Protocol Dest Port Action
A
B
C
D
E
In
Out
Out
In
Either
External Internal
Internal External
Internal
External
External Internal
Any
Any
a. Describe the effect of each rule.
TCP
TCP
TCP
TCP
Any
25
> 1023
25
> 1023
Permit
Permit
Permit
Permit
Any Deny
A
The following questions are related to HTTP protocol
Q1. The first line of a HTTP request from some client to some server is basically made of
where the web page file path is added. The path is shown as folders separated
by slash.
Q2. If an HTTP server responds to a client request and the response is a success, what is the http
code and string that marks a success response? Must provide the code and the string as they appear
in TCPDump or Wireshark traces. (note: use upper case for the string and also proper spacing in you
answers. Keep the order of the string and the code as seen in TCPDump)
Answer: code and string that marks a success response
Q3. What http header field is used to identify an address of a web page (i.e. the URI) that linked to
the resource currently being requested. This field indicates the last page the user/requester was on
by the time they link to the requested page.
Answer: The field that indicates the last page the user/requester was on is
Q4. What is the http…
Chapter 8 Solutions
EBK COMPUTER NETWORKING
Ch. 8 - Prob. R1RQCh. 8 - Prob. R2RQCh. 8 - Prob. R3RQCh. 8 - Prob. R4RQCh. 8 - Prob. R5RQCh. 8 - Prob. R6RQCh. 8 - Prob. R7RQCh. 8 - Prob. R8RQCh. 8 - Prob. R9RQCh. 8 - Prob. R10RQ
Ch. 8 - Prob. R11RQCh. 8 - Prob. R12RQCh. 8 - Prob. R13RQCh. 8 - Prob. R14RQCh. 8 - Prob. R15RQCh. 8 - Prob. R16RQCh. 8 - Prob. R17RQCh. 8 - Prob. R18RQCh. 8 - Prob. R19RQCh. 8 - Prob. R20RQCh. 8 - Prob. R21RQCh. 8 - Prob. R22RQCh. 8 - Prob. R23RQCh. 8 - Prob. R24RQCh. 8 - Prob. R25RQCh. 8 - Prob. R26RQCh. 8 - Prob. R27RQCh. 8 - Prob. R28RQCh. 8 - Prob. R29RQCh. 8 - Prob. R30RQCh. 8 - Prob. R31RQCh. 8 - Prob. R32RQCh. 8 - Prob. R33RQCh. 8 - Prob. P1PCh. 8 - Prob. P2PCh. 8 - Prob. P3PCh. 8 - Prob. P4PCh. 8 - Prob. P5PCh. 8 - Prob. P6PCh. 8 - Prob. P8PCh. 8 - Prob. P12PCh. 8 - Prob. P13PCh. 8 - Prob. P14PCh. 8 - Prob. P18PCh. 8 - Prob. P20PCh. 8 - Prob. P21PCh. 8 - Prob. P22PCh. 8 - Prob. P23P
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