Computer Networks Multiple Choice Questions on “SMTP”.
1. When the mail server sends mail to other mail servers it becomes ____________
a) SMTP server
b) SMTP client
c) Peer
d) Master
Answer: b
Clarification: SMTP clients are the entities that send mails to other mail servers. The SMTP servers cannot send independent mails to other SMTP servers as an SMTP server. There are no masters or peers in SMTP as it is based on the client-server architecture.
2. If you have to send multimedia data over SMTP it has to be encoded into _______
a) Binary
b) Signal
c) ASCII
d) Hash
Answer: c
Clarification: Since only 7-bit ASCII codes are transmitted through SMTP, it is mandatory to convert binary multimedia data to 7-bit ASCII before it is sent using SMTP.
3. Expansion of SMTP is ________
b) Simple Message Transfer Protocol
c) Simple Mail Transmission Protocol
d) Simple Message Transmission Protocol
Answer: a
Clarification: SMTP or Simple Mail Transfer Protocol is an application layer protocol used to transport e-mails over the Internet. Only 7-bit ASCII codes can be sent using SMTP.
4. In SMTP, the command to write receiver’s mail address is written with the command _______
a) SEND TO
b) RCPT TO
c) MAIL TO
d) RCVR TO
Answer: b
Clarification: RCPT TO command is followed by the recipient’s mail address to specify where or to whom the mail is going to through the internet. If there is more than one receiver, the command is repeated for each address continually.
5. The underlying Transport layer protocol used by SMTP is ________
a) TCP
b) UDP
c) Either TCP or UDP
d) IMAP
Answer: a
Clarification: TCP is a reliable protocol, and Reliability is a mandatory requirement in e-mail transmission using SMTP.
6. Choose the statement which is wrong incase of SMTP?
a) It requires message to be in 7bit ASCII format
b) It is a pull protocol
c) It transfers files from one mail server to another mail server
d) SMTP is responsible for the transmission of the mail through the internet
Answer: b
Clarification: In SMTP, the sending mail server pushes the mail to receiving mail server hence it is push protocol. In a pull protocol such as HTTP, the receiver pulls the resource from the sending server.
7. Internet mail places each object in _________
a) Separate messages for each object
b) One message
c) Varies with number of objects
d) Multiple messages for each object
Answer: b
Clarification: It places all objects into one message as it wouldn’t be efficient enough if there are different messages for each object. The objects include the text and all the multimedia to be sent.
8. Typically the TCP port used by SMTP is _________
a) 25
b) 35
c) 50
d) 15
Answer: a
Clarification: The ports 15, 35 and 50 are all UDP ports and SMTP only uses TCP port 25 for reliability.
9. A session may include ________
a) Zero or more SMTP transactions
b) Exactly one SMTP transactions
c) Always more than one SMTP transactions
d) Number of SMTP transactions cant be determined
Answer: a
Clarification: An SMTP session consists of SMTP transactions only even if no transactions have been performed. But no transactions in the session might mean that the session is inactive or is just initiated.
10. Which of the following is an example of user agents for e-mail?
a) Microsoft Outlook
b) Facebook
c) Google
d) Tumblr
Answer: a
Clarification: Among the options, only Microsoft Outlook is an e-mail agent. Google is a search engine and Facebook, and Tumblr are social networking platforms. Gmail and Alpine are some other examples of e-mail agent.
11. When the sender and the receiver of an email are on different systems, we need only _________
a) One MTA
b) Two UAs
c) Two UAs and one MTA
d) Two UAs and two MTAs
Answer: d
Clarification: The sender’s User Agent (UA) submits the message to a Message Transfer Agent (MTA). Then the MTA sends the message to another MTA i.e. a mail relay. Then the receiver receives the message from the mail relay whenever it is available.
12. User agent does not support this ___________
a) Composing messages
b) Reading messages
c) Replying messages
d) Routing messages
Answer: d
Clarification: The user agent is basically a software program that allows the user to send, and receive e-mail messages. Routing of the message is done by the Message Transfer Agent.