Computer  Science 481/681
                        Quiz 4  -         Name ________________________

1. Last week we discussed RFC 1393.. The proposed replacement for
   the traceroute command.  The proposal claim to be an improvement
   because it:

   a. Reduced the total number        b. Eliminated problems that dynamic
      of transmissions required.         routing changes cause traceroute.

   c. Both a. and b.                  d. Neither a. or b. was a factor.


2. The proposal involved both the use of ICMP and a new "trace route"
   option in IP headers.  The use of the trace route header option in
   the ICMP traceroute packets RETURNED to the original sender

   a. Is mandatory.                   b. Is not required but its use
                                         would not be harmful.

   c. is undesirable and could cause
      major problems.

3. When a router received a message with the traceroute IP header
   option on it should:

   a. Always send an ICMP traceroute  b. Only send the ICMP traceroute
      packet back to the source.         if the router itself was
                                         the destination
   c. Never send an ICMP traceroute
      packet back (since that was the
      responsibility of the dest host.

4. Source routing involves the use of

   a. IP header options               b. ICMP packets

   c. both                            d. neither

5. Suppose station 130.127.48.99 has the following routing table:
   (assume a subnet mask of 255.255.255.0 for all elements)

Destination       Gateway     Flags    Refcnt Use     Interface
130.127.15.11   130.127.48.7  UGHD     0      5          le0
130.127.15.8    130.127.48.7  UGHD     0      5          le0
130.127.75.9    130.127.48.2  UGHD     0      8          le0
130.127.44.2    130.127.48.4  UGHD     0      1          le0
default         130.127.48.1  UG       0      942        le0
130.127.48.0    130.127.48.24 U        27     1022954    le0

Draw a diagram of the network showing the address of each lan
and each interface that can be determined from the table.












6. Answer the following "T" or "F"

   ___ a. An H in a routing table entry means that the destination
          host can be reached in a single transmission.

   ___ b. The absence of G in a routing table entry means that the
          destination host or network can be reached in a single
          transmission.

   ___ c. The D option in a routing table meant that the entry had
          timed out and was logically deleted.

7. One of the "rules" governing the issuance of ICMP redirects was
   that the router must be configured to do so. Identify one other
   condition that should be verified before a router issues a redirect:






8. One of the "rules" governing the honoring or ICMP redirects is
   that the specified new router can't be the original source of
   the message. Identify one other condition that must be true before
   a redirect should be honored.




9. The code value in the ICMP redirect message specifies whether or
   not the redirect was for a host or an entire network address. It
   also specifies if the redirect applies to:

   a. A particular transport       b. A particular type of
      protocol (UDP, TCP, etc)        service

   c. A particular length of       d. All of the above.
      time.