The current standard is version 4 revision 1 of the protocol (IMAP4rev1).
Most IMAP clients generally leave messages on the server unless the user decides to delete them.
This enables multiple clients to connect and manage the same mailbox on an IMAP server simultaneously.
The default port number that an IMAP server listens on is 143.
The server requires a username and password to authenticate a client.
TLS/SSL are cryptographic protocols for secure communication over computer networks.
They are based on the exchange of X.509 certificates and public keys for encrypting and decrypting messages.
Digital certificates are issued by a certificate authority (CA) trusted by both parties involved in the communication.
This directly affects the quality of your service, because your clients or employees rely on email every day.
If the server uses TLS/SSL security, it is also important to monitor the certificate expiration date.
