Which of the following are Internet standard protocols for email retrieval?
Each correct answer represents a complete solution. Choose two.

A.
SNMP

B.
POP3

C.
SMTP

D.
IMAP4

Explanation:

IMAP4 and POP3 protocols are Internet standard protocols for email retrieval.
Internet Message Access Protocol 4 (IMAP4) is an e-mail message retrieval protocol that allows email clients to retrieve e-mail messages from e-mail servers.
Post Office Protocol version 3 (POP3) is a protocol used to retrieve e-mails from a mail server. It is
designed to work with other applications that provide the ability to send e-mails. POP3 is mostly
supported by the commercially available mail servers. It does not support retrieval of encrypted emails. POP3 uses port 110.
Answer option A is incorrect. Simple Network Management Protocol (SNMP) is a part of the TCP/IP
protocol suite, which allows users to manage the network. SNMP is used to keep track of what is
being used on the network and how the object is behaving.

Answer option C is incorrect. Simple Mail Transfer Protocol (SMTP) is a protocol for sending e-mail
messages between servers. E-mailing systems use this protocol to send mails over the Internet.
SMTP works on the application layer of the TCP/IP or OSI reference model. The
SMTP client typically initiates a Transmission Control Protocol (TCP) connection to the SMTP server
on the well-known port designated for SMTP, port number 25. However, e-mail clients require POP
or IMAP to retrieve mails from e-mail servers.
Reference: “http://en.wikipedia.org/wiki/Internet_Message_Access_Protocol”