This chapter is challenging, exciting, and, ocassionally, maddening. In addition to the difficulty of the individual pieces, students have the challenge of putting them together. They should think in terms of the ultimate goal which is data transfer so they need three programs:

1. A gateway program.

2. A server program.

3. A client program.

This chapter is very difficult. Keeping in mind that Calvin is an undergraduate institution

1. I plan to use it as a major project.
2. I may decide to give the students part of the project.
3. I will set out clear layers of expectations depending on the abilities and experience of the students. At the risk of trying to predict what will happen four months from now, I expect one or two students to do essentially the whole project. I expect 3-5 students to get through 8.3. I expect 3-5 students to get through 8.2. The rest of a class of 12 will not be able to do this. I will let you know.

   Experiment 8.4 presents special difficulties. You have to take into account all the vagaries of datagram transmission, packets lost, corrupted, delivered out of order, etc. The use of a timer complicates debugging (UNDERSTATEMENT). The coordination of three programs is an ongoing headache. In spite of all this, this is an extremely rewarding project.