SMTP, simple mail transfer protocol, typically running on port 25, is a protocol used by mail servers and programs to send and receive email.
POP, post office protocol, typically running on port 110, is a protocol used by email users to get access to the email stored on their mail servers.
In the real world an email will a follow a path such as :
POP, post office protocol, typically running on port 110, is a protocol used by email users to get access to the email stored on their mail servers.
In the real world an email will a follow a path such as :
- User sends email using SMTP to their outgoing mail server
- That outgoing mail server relays the email using smtp through one or more mail servers
- The destination mail server receives the email using SMTP
- The destination user retrieves their email from that server using POP