Data Communication and Computer Networks Set 3

Data Communication and Computer Network

Questions and Answers 21 to 30

21.	HTTP (Hyper Text Transfer Protocol) has similarities to both of the following protocols (a)  FTP; SMTP                                      (b)  FTP; SNMP (c)  FTP; MTV                                        (d)  FTP; URL          (e)  SMTP; SNMP
22.	What is the bit combination used by the SAPI field of ISDN’s data link layer, to control call for end-to-end signaling in LAPD addressing format? (a)  000000              (b)  000010              (c)  010000              (d) 000001                               (e)  111111.
23.	Which category of AAL of ATM is intended to support connection-oriented data services? (a)  AAL1                 (b)  AAL2                (c)  AAL3                 (d)  AAL4                              (e)  AAL5.
24.	In the process of congestion control, the bits FECN and BECN of frame relay protocol are useful to (a)   Warn sender and receiver of congestion in the network respectively (b)   Warn receiver and sender of congestion in the network respectively (c)   Warn only receiver of congestion in the network respectively (d)   Warn only sender of congestion in the network respectively (e)   Indicate the congestion but no warning to either sender or receiver is given
25.	MIME allows what type of data to be sent through SMTP? (a)  Audio                                              (b)  Non-ASCII data (c)  Image                                              (d)  Video                             (e)  All of the above.
26.	Which of the following application protocol is a framework for managing devices in an internet using the TCP/IP protocol suite. (a)  SMTP                (b)  SNMP               (c)  FTP                   (d)  TELNET                               (e)  HTTP.
27.	Which of the following component of SMTP can transform non-SMTP mail to SMTP format and vice versa. (a)  mail spool         (b)  mail gateway                                   (c)  mail file (d)  mail exchanger (e)  none of the above.
28.	What names objects, defines the type of data that can be stored in an object, and encodes data for network transmission. (a)  MIB                   (b)  SMI                   (c)  SNMP               (d)  ASN.1                              (e)  BER .
29.	Flow Control in data communications (a)   Can be implemented using a CSMA/CD Protocol (b)   Makes a channel an error-free one. (c)   Can be implemented using a Stop-and-Wait Protocol (d)   Cannot be implemented on a simplex link (e)   None of the above.
30.	Which of the following is not correct regarding the Simple Mail Transfer Protocol (SMTP) and Post Office Protocol3 (POP3)? (a)   SMTP delivers email by having the source machine establish a TCP connection to port 25 of the destination machine (b)   SMTP and POP3  are  simple one ASCII protocols (c)   POP3 uses the port 20 by default to establish a connection (d)   POP3 is used for fetching email from a remote mailbox (e)   SMTP provides for mail exchange between users on the same or different computers.

Answers

21.	Answer :  (a) Reason : HTTP functions like a combination of FTP and SMTP . It is similar to FTP because it transfers files and uses the services of TCP. However , it is much simpler than FTP because it uses only one TCP connection.  HTTP is like SMTP because the data transferred between the client and the server look like SMTP messages.
22.	Answer : (d) Reason: 000001 bit combination used by the SAPI field of ISDN’s data link layer, to control call for end-to-end signaling in LAPD addressing format.
23.	Answer :  (c) Reason : AAL3 of ATM is intended to support connection-oriented data services.
24.	Answer :  (b) Reason : In the process of congestion control, the bits FECN and BECN of frame relay protocol are useful to Warn receiver and sender of congestion in the network respectively.
25.	Answer : (e) Reason : MIME allows audio, non-ASCII , video and image of data to be sent through SMTP.
26.	Answer :  (b) Reason : SNMP (Simple Network Management Protocol) is a framework for managing devices in an internet using the TCP/IP protocol suite.
27.	Answer :  (b) Reason : Mail gateway is the component of SMTP can transform non-SMTP mail to SMTP format and vice versa.
28.	Answer :  (b) Reason : SMI  is the  names objects, defines the type of data that can be stored in an object, and encodes data for network transmission.
29.	Answer : (c) Reason : Flow Control in data communications can be implemented using a Stop-and-Wait Protocol
30.	Answer :  (c) Reason : POP3 uses the port 20 by default to establish a connection is not correct regarding the Simple Mail Transfer Protocol (SMTP) and Post Office Protocol3 (POP3).