Email is the preferred method of communication for businesses, but is effectively a plaintext communication sent from email clients to receiving email servers or from one server to another, leaving the content of messages in transit vulnerable to compromise without additional protection via encryption technology such as the Transport Layer Security (TLS) standard.

What Is TLS & How Does It Help Keep Email Private?

TLS is a cryptographic protocol that offers end-to-end encryption technology for messages “in transit” from one secure email server that has TLS enabled to another,  helping to protect user privacy and prevent eavesdropping or content alteration. For optimal security and privacy of message content, TLS is required between all servers handling email communications (including hops between internal and external servers). 

TLS secures email communications by encrypting messages from mail server to mail server, making it more difficult for hackers to intercept and read messages. “Opportunistic TLS” describes a scenario in which TLS is used by both sending and receiving parties to negotiate a secured session and encrypt a message, and represents the most secure implementation of the TLS protocol.

It is recommended that all clients and servers insist on mandatory usage of TLS in their email communications - preferably the most recent version, TLS 1.3.

Next Steps

You can read more about how TLS helps to secure email communications and how to configure TLS for the Postfix mail Transfer Agent (MTA), Microsoft 365 Exchange Online and Google Workspace to help secure your email communications in a recent blog post.

Want to learn more about how to protect the privacy of your email with TLS? Get in Touch>>

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