Chapter 2 Review

What information is used by a process running on one host to identify a process running on another host?

(1) the IP address, to identify the machine (2) the Port number, to identify the program/application.

Is P-2-P client, server, or both?

Both. You are the client when you download files from other people. But when other people download your files, you are the server. You can act like a client and a server at the same time.

A non-proprietary internet application and the application-layer protocols it uses: Google Flights

DNS lookup and http.

A non-proprietary internet application and the application-layer protocols it uses: E-mail

DNS lookup, SMTP, IMAP and POP.

A non-proprietary internet application and the application-layer protocols it uses: Peer-to-Peer File Sharing (P-2-P)

Gnutella, BitTorrent. (P-2-P is a hybrid, and also uses client-server).

What is an example of an application that requires no data loss and that is also highly time-sensitive?

High-frequency stock trading Text messaging

For a communication session between a pair of processes, which process is the client and which is the server?

The client starts the whole thing. The server waits for requests.

Suppose you want to do a transaction from a remote client to a server as fast as possible. Would you use UDP or TCP?

UDP is faster. There is no handshake (a round-trip), and there is no congestion control and flow control. The handshake, congestion- and flow control slow down TCP.