Homework 2

Please do the following problems.
  1. Problem 2.4 (both books)
  2. Problem 2.7 (8e) A TCP segment consisting of 1500 bits of data and 160 bits of header. This is then transmitted through two networks, each of which uses a 24-bit packet header. The destination network has a maximum packet size of 800 bits. How many bits, including headers, are delivered to the network layer protocol at the destination?
  3. Problem 2.8 (8e) Why is UDP needed? Why can't a user program directly access IP?
  4. Problem 2.11 (8e), This is 2.8 in (7e)
  5. Problem 2.14 (8e). The TFTP specification (RFC 1350) states that the transfer identifiers (TIDs) chosen for a connection should be randomly chosen, so that the probability that the same number is chosen twice in immediate succession is very low. What would be the problem of using the same TIDs twice in immediate succession?
  6. 2.15 (8e) In order to be able to retransmit lost packets, TFTP must keep a copy of the data it sends. How many packets of data must TFTP keep at a time to implement this retransmission mechanism?