Email Security Protocols :
Email security protocols are the structures that protect your email from outside interference. Your email needs additional security protocols for a very good reason.
Secure Sockets Layer (SSL) and its successor, Transport Layer Security (TLS), are the most common email security protocols that protect your email as it travels across the internet.
SSL and TLS are application layer protocols. In internet communication networks, the application layer standardizes communications for end-user services. In this case, the application layer provides a security framework (a set of rules) that works with SMTP (also an application layer protocol) to secure your email communication.
From herein, this section of the article discusses TLS as its predecessor, SSL, was fully deprecated in 2015.
TLS provides additional privacy and security for communicating computer programs. In this instance, TLS provides security for SMTP.