Computer  Science 826
                          Quiz 9  -         Name ________________________

1. Suppose I am a malicious hacker trying to use ICMP redirects
   to divert the traffic of a victim machine to myself. Suppose
   the following IP addresses are in use:

   my address               130.127.48.24
   victim's address         130.127.48.13
   victim's intended dest   130.127.72.12
   victim's default router  130.127.48.2

   In the ICMP redirect spoofing packet that I SEND what IP address
   do I use for each of the following:

   a. Source IP address:


   b. Dest IP address:


   c. ICMP data:


2. ICMP redirects can be generated by a router

   a. Only when the router forwards   b. Only when the router forwards
      a packet on the same interface     a packet on a different interface
      on which it arrived.               from the one on which it arrived.

   c. It is OK in both cases.

3. Answer the following T or F

   ___ a. An ICMP redirect should never be generated if the
          destination address in the IP header is a on different
          network or subnetwork from the one on which the packet
          arrived.

   ___ b. An ICMP redirect should never be generated if a packet
          must be retransmitted using the same interface on which
          it arrived.

   ___ c. A received ICMP redirect should be discarded if the receipient
          is not directly connected to the sender.

   ___ d. A received ICMP redirect should be discarded if the new router
          specifed is not directly connected to the sender.

4. The router advertisement protocol we discussed in class
    uses:

    a. Raw IP packets            b. ICMP packets

    c. UDP packets               c. TCP packets

5. The primary purpose of the router advertisement protocol
   is to

   a. Provide a way for routers on   b. Provide a way for routers
      a LAN to advertise their          to make their presence known
      presence to clients on the        across AS boundaries.
      same LAN.

   c. Provide a way for clients to   d. All of the above
      request information on how
      to build a source route to
      a distant client.

6. Characterize "permissive" and "non-permissive" filter rules:

   ___ a. permissive             1. Safe and unobtrusive

                                 2. Safe and obtrusive
   ___ b. non-permissive
                                 3. Unsafe and unobtrusive

                                 4. Unsafe and obtrusive

7. In addition to providing slightly better intrusion protection
   what other major benefit does use of a NAT gateway provide that
   is NOT provided by simply installing firewalls such as the one
   described in class.





8. In outgoing packet the NAT gateway typically translates:

   a. Source IP                 b. Source Port

   c. Dest IP                   d. Dest Port

   e.  a. and b.                f. c. and d.

   g. all of the above

9. In incoming packet the NAT gateway typically translates:

   a. Source IP                 b. Source Port

   c. Dest IP                   d. Dest Port

   e.  a. and b.                f. c. and d.

   g. all of the above

10. In incoming packet the ONE item that can suffice as
    a table lookup key is:

    a. Source IP                 b. Source Port

    c. Dest IP                   d. Dest Port