| 2.1 | We have mentioned IP versions 4 and 6. What happened to version 5 and what were versions 0, 1, 2, and 3? (Hint: Find the IANA's "Internet Protocol" registry. Feel free to skip ahead to the solution if you cannot visit http://www.iana.org.) |
| 2.2 | Where would you look to find more information about the protocol that is assigned IP version 5? |
| 2.3 | With Figure 2.15, we said that TCP assumes an MSS of 536 if it does not receive an MSS option from the peer. Why is this value used? |
| 2.4 | Draw a figure like Figure 2.5 for the daytime client/server in Chapter 1, assuming the server returns the 26 bytes of data in a single TCP segment. |
| 2.5 | A connection is established between a host on an Ethernet, whose TCP advertises an MSS of 1,460, and a host on a Token Ring, whose TCP advertises an MSS of 4,096. Neither host implements path MTU discovery. Watching the packets, we never see more than 1,460 bytes of data in either direction. Why? |
| 2.6 | In Figure 2.19, we said that OSPF uses IP directly. What is the value of the protocol field in the IPv4 header (Figure A.1) for these OSPF datagrams? |
| 2.7 | In discussing SCTP output, we said that the SCTP sender must wait for the cumulative acknowledgment point to pass sent data before the data could be freed from the socket buffer. If a selective acknowledgment shows that data is acknowledged beyond the cumulative acknowledgment point, why can't the data be freed? |
