Chapter 7. Connection-oriented Nets: X.25 and ATM

This chapter covers connection-oriented networks, discussing X.25 and ATM in detail. Although X.25 may be dying out, I think it's worth studying as an example of a connection-oriented reliable network layer. There are all sorts of fascinating details—for example, that the sequence number when launched by the source can be different from the sequence number as received by the destination. And when you understand X.25 you can easily understand ATM.