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Which of the following is NOT an email protocol?
- SMTP
- IMAP
- NTP
- POP
Explanation:
Network Time Protocol (NTP) is used to synchronize the clock of computers on the network. Synchronization of time is important in areas such as event logs, billing services, e-commerce, banking and HIPAA Security Rules.
Simple Mail Transport Protocol (SMTP) is an application protocol, so it operates at the top layer of the OSI model. SMTP is the default protocol for sending e-mail in Microsoft operating systems. SMTP provides client and server functions and works with the Internet and UNIX. it is used to send and receive messages.
Post Office Protocol version 3 (POP3) and Internet Mail Access Protocol 4 (IMAP4) are client email programs. They are used to retrieve email from the server. POP3 and IMAP are the most popular protocols for receiving e-mail protocols.
The following is a list of the common ports in use:
– TCP Port 20 – FTP (File transfer Protocol) data
– TCP Port 21 – FTP
– TCP Port 22 – Secure Shell (ssh), Secure Copy (scp), or Secure FTP (SFTP)
– TCP Port 23 – Telnet
– TCP Port 25 – Simple Mail Transfer Protocol (SMTP)
– TCP/UDP Port 53 – Domain Name System (DNS)
– UDP Port 67 Dynamic Host Configuration Protocol (DHCP) Server
– UDP Port 68 Dynamic Host Configuration Protocol (DHCP) Client
– TCP Port 80 HyperText Transfer Protocol (HTTP)
– TCP Port 110 – Post Office Protocol version 3 (POP3)
– TCP Port 123 – Network Time Protocol (NTP)
– TCP Port 143 – Internet Mail Access Protocol
Objective: Security Monitoring
Sub-Objective: Describe the function of these protocols in the context of security monitoring: DNS, NTP, SMTP/POP/IMAP, HTTP/HTTPS
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