What advantage would this have over the scheme described in the text?

PROBLEMS

1. In our example transport primitives of Fig. 6-2, LISTEN is a blocking call. Is this strictly necessary? If not, explain how a nonblocking primitive could be used. What advantage would this have over the scheme described in the text?

2. Primitives of transport service assume asymmetry between the two end points during connection establishment, one end (server) executes LISTEN while the other end (client) executes CONNECT. However, in peer to peer applications such file sharing systems, e.g. BitTorrent, all end points are peers. There is no server or client functionality. How can transport service primitives may be used to build such peer to peer applications?

3. In the underlying model of Fig. 6-4, it is assumed that packets may be lost by the network layer and thus must be individually acknowledged. Suppose that the network layer is 100 percent reliable and never loses packets. What changes, if any, are needed to Fig. 6-4?

4. In both parts of Fig. 6-6, there is a comment that the value of SERVER PORT must be the same in both client and server. Why is this so important?

5. In the Internet File Server example (Figure 6-6), can the connect( ) system call on the client fail for any reason other than listen queue being full on the server? Assume that the network is perfect.

6. One criteria for deciding whether to have a server active all the time or have it start on demand using a process server is how frequently the service provided is used. Can you think of any other criteria for making this decision?