Computer Networks Multiple Choice Questions on “Ports”.
1. Multiple objects can be sent over a TCP connection between client and server in a persistent HTTP connection.
a) True
b) False
Answer: a
Clarification: Persistent connections are kept active after completing transaction so that multiple objects can be sent over the same TCP connection.
2. HTTP is ________ protocol.
a) application layer
b) transport layer
c) network layer
d) data link layer
Answer: a
Clarification: HTTP is an Application layer protocol used to define how messages are formatted and transmitted through the World Wide Web.
3. In the network HTTP resources are located by __________
a) Uniform resource identifier
b) Unique resource locator
c) Unique resource identifier
d) Union resource locator
Answer: a
Clarification: The Uniform Resource Identifier is a name and locator for the resource to be located by the HTTP. The URLs and URNs are derived through the identifier.
4. HTTP client requests by establishing a __________ connection to a particular port on the server.
a) User datagram protocol
b) Transmission control protocol
c) Border gateway protocol
d) Domain host control protocol
Answer: b
Clarification: HTTP clients perform requests using a TCP connection, because the TCP connection provides a more reliable service. UDP is not a reliable protocol, border gateway protocol is used on top of TCP, while domain host control protocol is a network layer protocol.
5. In HTTP pipelining __________
a) multiple HTTP requests are sent on a single TCP connection without waiting for the corresponding responses
b) multiple HTTP requests cannot be sent on a single TCP connection
c) multiple HTTP requests are sent in a queue on a single TCP connection
d) multiple HTTP requests are sent at random on a single TCP connection
Answer: a
Clarification: HTTP pipelining helps the client make multiple requests without having to waiting for each response, thus saving a lot of time and bandwidth for the client.
6. FTP server listens for connection on which port number?
a) 20
b) 21
c) 22
d) 23
Answer: b
Clarification: Port 20 is used for FTP data. Port 22 is used for SSH remote login. Port 23 is used for TELNET.
7. In FTP protocol, a client contacts a server using ______ as the transport protocol.
a) Transmission control protocol
b) User datagram protocol
c) Datagram congestion control protocol
d) Stream control transmission protocol
Answer: a
Clarification: The clients use the Transmission Control Protocol for FTP as it’s more reliable than UDP, DCCP, and SCTP, and reliability of file transfer is required to be as high as possible for FTP.
8. In Active mode FTP, the client initiates both the control and data connections.
a) True
b) False
Answer: b
Clarification: In Passive mode of FTP, the client initiates both data and control connections, while in Active mode, the client initiates the control connection and then the server initiates the data connection.
9. The File Transfer Protocol is built on __________
a) data centric architecture
b) service oriented architecture
c) client server architecture
d) connection oriented architecture
Answer: c
Clarification: The FTP connection includes a Server and a Client which wish to share files. The server can have multiple clients at the same time while the client communicates with only one server at a time.
10. In File Transfer Protocol, data transfer cannot be done in __________
a) stream mode
b) block mode
c) compressed mode
d) message mode
Answer: d
Clarification: In Stream mode, the data is transferred in a continuous stream. In Block mode, data is transferred after being divided into smaller blocks. In Compressed mode, data is transferred after being compressed using some compression algorithm.