TDC 375-701
Practice 3
Not graded

If you want to be well prepared for just about anything that might
be thrown at you on a quiz or exam, these are some additional practice
questions that will help get you there.  These questions will not be
graded and no answer sheet is provided.  If you want to check the
answers, come prepared to the next class and ask about 1 or 2 of them
(sorry won't have time to get to them all).

From TCP/IP Protocol Suite, 4th Edition, answer:
6.7, Questions 1-21, 22, 24, 26, 28
7.12, Questions 1-19

Also answer the following questions:

Q. Also answer question 6.7.28 using Juniper Networks as a vendor
   resource.


Q. Visit:

     <http://www.traceroute.org>

   Try to traceroute to your own IP address from multiple geographic
   traceroute servers.  If the option is available, try to traceroute
   from those servers to another well known host such as www.google.com.
   What do you observe when you traceroute to www.google.com from
   multiple, geographically dispersed traceroute servers?


Q. Visit and give the following online tool a whirl (requires Java):

     <http://netalyzr.icsi.berkeley.edu/>


Q. Install tcpdump, Wireshark and or related packet capture tools.
   Run traceroute to a remote system (tracert on Windows) and capture
   the packets involved.  Analyze the results.


Q. What will a router do when it receives an IP data whose TTL
   field is set to zero?


Q. Imagine two routers are directly connected with a single link.
   Router A's interface to Router B is configured to use the IP
   address 192.0.2.0.  Router B's interface to Router A is set to
   use 192.0.2.1 as its IP address.  The subnet mask used by both
   those addresses is /31.  Will this work?


Q. Find out what protocols traceroute on a UNIX/Mac system uses
   by default and what Windows uses by default.  Can you change
   the protocol?  What is the purpose for doing that?


Q. How far will a packet sent to destination address 255.255.255.255
   go if the TTL is set to 2?  What if it is set to 255?


Q. Consider what sorts of security issues there may be with the
   Internet Protocol simply by examining the protocol format and
   examining packet traces.  What sorts of problems might there
   be?  How might you defend against them?


Q. Why won't any single IP datagram travel around the Internet
   forever (say for example in an endless loop f one existed -
   yes its possible to get into a endless loop)?


Q. What is the IP Protocol field number for ICMP, UDP and TCP?
   Is there a protocol number for null, that is, for no upper
   layer protocol?


$Id: practice3.txt,v 1.1 2009/09/23 02:40:05 jtk Exp $