Chapter 2 Application Layer
1. In the following four descriptions, which one is correct? A In C/S architecture, clients communicate with each other directly. B In C/S architecture, client has a fixed well-known address. C In P2P architecture, peers communicate with each other directly. D In P2P architecture, peer has a fixed well-known address.
2. In the context of a communication session between a pair of process, the process that initiates the communication is labeled as the , the process that waits to be contacted to begin the session is labeled as the .
A client process, server process B sending process, receiving process C input process, output process D communicating process, connecting process 3. A socket is the interface between within a host. A the network layer and the link layer B the link layer and the physical layer C the application layer and the transport layer D the transport layer and the network layer
4. In the following applications, which one is a loss-tolerant application?
A E-mail B file transfer C instant messaging D real-time audio 5. In the following applications, which one is a bandwidth-sensitive application? A E-mail B web application C real-time audio D file transfer 6. The service of TCP can’t guarantee . A delivery of all data without error B delivery of all data in the proper order C the rate of delivery D congestion control 7. In the following applications, which one uses UDP?
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A E-mail B web application C file transfer D DNS 8. In the following descriptions about HTTP, which one is not correct? A HTTP uses non-persistent connections in its default mode. B HTTP uses TCP as its underlying transport protocol. C HTTP is a stateless protocol. D HTTP is client-server architecture.
9. Suppose a web page consists of a base HTML file, 5 JEPG images and a java applet, and also suppose HTTP uses persistent connection without pipelining, the total response time is . A 2RTT B 8RTT C 12 RTT D 14RTT
10. In HTTP response message, if the requested HTTP protocol version is not supported, the status code is . A 200 B 301 C 400 D 505 11. The port number of web application is .
A 25 B 20 C 80 D 53
12. A network entity that satisfies HTTP requests on the behalf of an origin web server is . A server farm B server stack C proxy server D edge server 13. In the following descriptions about persistent connection, which one is not correct? A The server leaves the TCP connection open after sending a response. B Each TCP connection is closed after the server sending one object.
C There are two versions of persistent connection: without pipelining and with pipelining. D The default mode of HTTP uses persistent connection with pipelining. 14. FTP uses two parallel TCP connections to transfer a file, there are .
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A control connection and data connection B receiving connection and sending connection C client connection and sever connection D program connection and process connection
15. In the following descriptions about FTP, which one is correct?
A FTP is p2p architecture. B FTP sends its control information out-of-band. C FTP uses persistent connection. D FTP is a stateless protocol. 17. The Internet mail system has three components which they are . A user agent, SMTP, POP3 B SMTP, POP3, IMAP C user agent, SMTP, IMAP D user agent, SMTP, mail server 18. If the status code in HTTP response message is 404, it means . A Request succeeded.
B The requested document doesn’t exit on this server.
C This is a generic error code indicating that the request could not be understood by the server.
D Requested object has been permanently mover. 19. Comparison HTTP with SMTP, the correct is . A HTTP is a push protocol, and SMTP is a pull protocol. B In the default mode, both of them use persistent connection.
C HTTP places all of the message’s objects into one message, and SMTP sends every object one by one.
D HTTP requires each message to be in 7-bit ASCII format, and SMTP doesn’t impose this restriction.
20. The headers in the MIME message must include except .
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A From B Content-type C Content-transfer-encoding D MIME version
21. In the following protocol, which one is stateless?
A POP3 B SMTP C FTP D IMAP 22. DNS means .
A Data Name System B Data National System C Domain Name System D Domain National System 23. There are three classes of DNS server except .
A Root DNS server B Local DNS server C TLD server D Authoritative DNS server 24. DNS provides some services except .
A Host aliasing B Mail server aliasing C Load distribution D A single point of failure
28. The time it takes for a small packet to travel from client to server and then back to the client is . A round-travel time B next-hop time C round-trip time D prefix-matching time
29. Suppose A ( with a Web-based e-mail account ) sends a message to B ( who accesses his mail server using POP3), which application-layer protocol is not used? A HTTP B SMTP C POP3 D IMAP
30. In the four following options, which protocol is included in Mail Access Protocol? A SMTP B DHCP C IMAP D FTP 31. In FTP commands, is used to send user password to the server. A User B Pass C Retr D Stor
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32. The function of the additional header field in MIME Content-Type is . A to convert the message body to its origin non-ASCII form B to determine what actions it should take on message body C to send an E-mail to the receiving user agent D to indicate what type the message is
33. In the four following options, which application is organized as hybrid of C/S and P2P architecture?
A E-mail B OICQ C File transfer D Web application 35. In the following options, from the application developer’s perspective, which is not correct?
A the network architecture is fixed
B the network architecture provides a specific set of services to applications C the application architecture is designed by the physical devices
D the application architecture dictates how the application is organized over the various end systems
36. There are three predominant architectures used in modern network applications, which one is not included?
A the client-server architecture B the P2P architecture C a hybrid of the client-server and P2P architecture
D a hybrid of the client-server and browser-server architecture 37. In the following options about C/S architecture, which is not correct? A In C/S architecture, there is an always-on host, called the server. B In C/S architecture, there is an always-on host, called the client. C The server has a fixed, well-known address, called IP address.
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