1、1Chapter 2 Application Layer1. 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 archite
2、cture, 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 sendin
3、g process, receiving processC input process, output process D communicating process, connecting process3. A socket is the interface between within a host. A the network layer and the link layerB the link layer and the physical layerC the application layer and the transport layerD the transport layer
4、 and the network layer4. In the following applications, which one is a loss-tolerant application? A E-mail B file transfer C instant messaging D real-time audio5. In the following applications, which one is a bandwidth-sensitive application? A E-mail B web application C real-time audio D file transf
5、er6. The service of TCP cant guarantee .A delivery of all data without error B delivery of all data in the proper orderC the rate of delivery D congestion control7. In the following applications, which one uses UDP? 2A E-mail B web application C file transfer D DNS8. In the following descriptions ab
6、out 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,
7、 and also suppose HTTP uses persistent connection without pipelining, the total response time is .A 2RTT B 8RTT C 12 RTT D 14RTT10. In HTTP response message, if the requested HTTP protocol version is not supported, the status code is .A 200 B 301 C 400 D 50515 CACDC 610 CDABD11. The port number of w
8、eb application is .A 25 B 20 C 80 D 5312. 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 server13. In the following descriptions about persistent connection, which one is not correct? A The server leaves the
9、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 T
10、CP connections to transfer a file, there are .3A control connection and data connectionB receiving connection and sending connectionC client connection and sever connectionD program connection and process connection15. In the following descriptions about FTP, which one is correct?A FTP is p2p archit
11、ecture. B FTP sends its control information out-of-band.C FTP uses persistent connection. D FTP is a stateless protocol.16. In the commands of FTP, which one does not have parameter? A USER B PASS C LIST D STOR17. The Internet mail system has three components which they are .A user agent, SMTP, POP3
12、 B SMTP, POP3, IMAPC user agent, SMTP, IMAP D user agent, SMTP, mail server18. If the status code in HTTP response message is 404, it means .A Request succeeded. B The requested document doesnt exit on this server.C This is a generic error code indicating that the request could not be understood by
13、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 messages objects into one message, and SMTP sends ever
14、y object one by one.D HTTP requires each message to be in 7-bit ASCII format, and SMTP doesnt impose this 4restriction.20. The headers in the MIME message must include except .A From B Content-type C Content-transfer-encoding D MIME version1115CCBAB 1620 DDBBD21. In the following protocol, which one
15、 is stateless? A POP3 B SMTP C FTP D IMAP22. DNS means .A Data Name System B Data National SystemC Domain Name System D Domain National System23. There are three classes of DNS server except .A Root DNS server B Local DNS serverC TLD server D Authoritative DNS server24. DNS provides some services ex
16、cept .A Host aliasing B Mail server aliasingC Load distribution D A single point of failure25. There are three architectures for locating content in P2P file sharing, KaZaA uses . A Centralized Directory （Napster） B Query Flooding(Gnutella)C Exploiting Heterogeneity (p141) D Incentive Priorities 26.
17、 There are three architectures for locating content in P2P file sharing, Napster uses .A Centralized Directory (p137) 5B Query Flooding C Exploiting Heterogeneity D Incentive Priorities27. The following architectures in P2P file sharing, which is an overlay network? A Centralized Directory B Query F
18、looding(p139) C Exploiting Heterogeneity D Incentive Priorities 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 timeC round-trip time D prefix-matching time29. Suppose A ( with a Web-based e-mail account ) sends
19、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 IMAP30. In the four following options, which protocol is included in Mail Access Protocol? A SMTP B DHCP C IMAP D FTP31. In FTP commands, is used to send user password to t
20、he server.A User B Pass C Retr D Stor32. The function of the additional header field in MIME Content-Type is .A to convert the message body to its origin non-ASCII formB to determine what actions it should take on message bodyC to send an E-mail to the receiving user agentD to indicate what type the
21、 message is633. 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 application34. In the four following options, which is not a centralized DNS designs problem? A a single point of failure B traffic volume C dist
22、ant centralized database D slow (maintenance)35. In the following options, from the application developers perspective, which is not correct? A the network architecture is fixedB the network architecture provides a specific set of services to applicationsC the application architecture is designed by
23、 the physical devicesD the application architecture dictates how the application is organized over the various end systems36. There are three predominant architectures used in modern network applications, which one is not included? A the client-server architecture B the P2P architectureC a hybrid of
24、 the client-server and P2P architectureD a hybrid of the client-server and browser-server architecture37. 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, cal
25、led the client.C The server has a fixed, well-known address, called IP address.7D Clients do not directly communicate with each other.38. are often used to create a powerful virtual server in C/S architecture. A Peers B Server farm C server stack D local server39. A process sends messages into, and
26、receives messages from, the network through its .A socket B program C client D peer40. Which one is not defined by an application-layer protocol? A the types of messages exchangedB the syntax of various message typesC the semantics of the fieldsD rules for determining when and how to translate the s
27、ocket41. HTTP can use two types of connections, which are .A persistent and non-persistent connectionB connection with pipelining and without pipeliningC TCP and UDPD parallel and serial connection42. takes for a small packet to travel from client to server and then back to the client.A RDT B thresh
28、old C RTT D overhead43. The default mode of HTTP uses .A non-persistent connection with pipeliningB non-persistent connection without pipeliningC persistent connection with pipeliningD persistent connection without pipelining44. In HTTP request messages, the request line has three fields, there are
29、.A the method field, the URL field and the HTTP version field8B the method, the connection and URL fieldC the user-agent, the method and HTTP version fieldD the user-agent, the URL and the HTTP version field45. In the header lines of HTTP request message, if the field of Connection is close, it spec
30、ifies .A the host on which object residesB what type of the user agentC that the browser wants the server to close the connection after sending the requested objectD which language can the browser receive46. In HTTP response message, if the status code is 404, it means .A request succeeded and the i
31、nformation is returned in the responseB requested object has been permanently movedC the requested HTTP protocol version is not supported by the serverD the requested document does not exist on this server47. is a network entity that satisfies HTTP requests on the behalf of an origin Web server.A pr
32、oxy server B local server C DNS server D Web server48. In the following four options about web cache, which one is not correct? A A web cache is both a server and a client at the same time.B A web cache is purchased and installed by an ISP.C A web cache can raise the response time for a client reque
33、st.D A web cache can reduce traffic on an institutions access link to the Internet.49. The request message in the conditional GET must include the header line.9A Last-Modified B Last-ReferencedC If-Modified-Since D If Referenced-Since50. FTP uses two parallel connections to transfer a file, they are
34、 .A TCP and UDP connectionB connection with pipelining and without pipeliningC control an data connectionD client-server and browser-server connection51. In FTP commands, which one is used to ask the server to send back a list of all files in the current remote directory? A USER B PASS C LIST D RETR
35、52. In the Internet mail system, allow users to read, reply to, forward, save and compose message.A User agents B mail servers C SMTP D TCP53. The two key MIME headers for supporting multimedia are .A Content-Type and MIME-VersionB Content-Type and Content-Transfer-EncodingC Content-Transfer-Encodin
36、g and MIME-VersionD MIME-Version and MIME-Type54. For Internet mail, the mail access protocol is used to .A transfer mail from the recipients mail server to the recipients user agentB transfer mail from the senders mail server to the recipients mail serverC translate the mail from the senders mail s
37、erverD translate the mail into the recipients mail server55. POP3 progresses through three phases, which they are .10A authorization, translation and transactionB authorization, translation and updateC authorization, transaction and updateD translation, transaction and update56. In the following fou
38、r services, which one can not provide by DNS? A Host aliasing B Mail server aliasingC translate hostname to IP addressesD translate MAC addresses to IP addresses57. There are three classes of DNS servers, there are .A root DNS server, top-level domain DNS server and local DNS serverB root DNS server
39、, top-level domain DNS server and authoritative DNS serverC root DNS server, local DNS server and authoritative DNS serverD root DNS server, local DNS server and top-level domain DNS server58. In the following four options about POP3, which one is not correct? A The user agent employed only three co
40、mmands: List, Retr and QuitB The server does not carry state information across POP3 sessionsC The port number is 110D The POP3 protocol does not provide any means for a user to create remote folders and assign messages to folders.59. A resource record in DNS distributed database is a four-tuple, wh
41、ich field can be ignored?(p132) A Name B Value C Type D TTL60. In the following four options about DNS resource record, which one is correct? 11A The meaning of Name and Value depend on Type. B The meaning of Value and Type depend on Name. C If Type=A, then Name is a domain and Value is the IP addre
42、ss for the hostname. D If Type=MX, then Name is domain and Value is the IP address for the hostname. 61. In the following four options about DNS messages, which one is not correct? A There are only two kinds of DNS message.(p133) B Both query and reply message have the same format. C The header sect
43、ion in DNS message has 12 bytes. D The authority section contains the resource records for the same that was originally queried. 62. In DNS message, contains information about the query that is being made.(p133) A authority section B question section C answer section D additional section63. There ar
44、e three techniques are employed in most any P2P file-sharing systems, which one is not include? （p144） A Request queuing B incentive priorities C parallel downloading D Response queuing64. In the following four options about P2P file-sharing, which one is not correct? A P2P file-sharing is highly sc
45、alable.B P2P file-sharing relies on P2P architecture.C The means for locating content in different P2P file-sharing are different.D P2P file-sharing systems not only share MP3s,but also videos, software, documents and images.65. In MIME header lines, specifies the name of the SMTP server that sent t
46、he message (from), the name of the SMTP server that received the message (by), and the time an which the receiv12ing server received the message. A Received B From C To D MIME-Version 66. If the header line Connection is close, it means that the client wants .A persistent connection with pipeliningB
47、 persistent connection without pipeliningC nonpersistent connectionD not connection67. In HTTP request message, the entity body is empty with the method, but is used with the method.A GET, POST B POST,GET C GET, HEAD D POST, HEAD68. In HTTP response message, if the Date: header ;one indicates the time Fri. 08 Aug. 2008 12:00:00 GMT, the Last-Modified: header line can not be .A Fri. 08 Aug. 2008 11:00:00 GMT B Fri. 08 Aug. 2008 11:30:00 GMTC Fri. 08 Aug. 2008 12:00:00 GMT D Fri. 08 Aug. 2008 12:30:00 GMT69. In the following four options, which one is not the part of cookie tec
