Secure Emails with PGP, SSL, TLS, Enforced TLS and S/MIME

Email protocols were considered insecure until the introduction of SSL and TLS. The basic protocols (SMTP, POP3 and IMAP4) did not have the mechanism to encrypt and provide data integrity for mail messages between two connections. Initially, SSL was added to email clients and later its successor, the TLS (SSLv3), was added to mail clients as well as to the SMTP protocol.Before the introduction of SSL and TLS, email protocols were considered insecure.

The basic protocols (SMTP, POP, and IMAP) did not have the mechanism to encrypt and provide data integrity for mail messages between two connections. Initially, SSL was added to email clients and later its successor, the TLS (SSLv3), was added to mail clients as well as to the SMTP protocol.

SMTP with TLS provides encryption and authentication. When both the client and the server (mail client and SMTP server or two SMTP servers) support TLS they both encrypt all data communications (passwords as well as the email message body itself) and guard against eavesdroppers. This is critical for companies that require by law or are concern about transferring sensitive data over the public Internet.

At Simplicato, we realized that these protocols are mandatory for some of our customers, which are in the financial and insurance businesses. All our servers are configured to handle SSL and TLS for mail clients and SMTP servers.