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101 Guide
3 min

What Is Secure Email? Guide To Email Encryption And Authentication

Posted by Picture of Sam Kendall Sam Kendall

Secure email solutions use email encryption and identity authentication to protect email contents from interception and manipulation, ensuring messages are delivered to the right people. Secure email software often includes additional features such as outbound security triggers, audit trails, and access control.Mailock free account signup banner

What's the risk?

Email was invented a long time ago. It hasn't changed much since, but the world around it has. The internet has become a centre for communication, making email a valuable target for those who would exploit it.

The need for cross-compatibility puts limits on how much the underlying technology behind email can change to meet rising threats. This means emails and attachments sent "in the clear" can be intercepted unless an encryption tool is used. They can also be accessed within recipient inboxes if credentials are stolen and an account is taken over.

This is not a problem for everyday emails, but for businesses and individuals sending confidential documents it can be costly.

Who is secure email designed for?

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Secure email can be used by anyone who needs to send sensitive information or documents and make sure they reach the right people. Most often, secure email is used by businesses in regulated sectors to deliver important information to customers, colleagues, and partners without exposing it to email risk.

How does secure email work?

Secure emails work just like email, with some added security benefits.

End-to-end encryption is used to disguise the contents, metadata, and attachments of an email so it can't be opened without the right key.

To obtain the right key, a recipient must pass an authentication challenge requiring them to verify their identity (for example, by answering a secret question or by entering an SMS code). This is called multi-factor authentication and it is effective at blocking 99.9% of automated cyber-attacks.

What data needs protecting?

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Sending sensitive information via open-risk email, whether by negligence or accident, can be harmful.

Regulators have the authority to impose fines on businesses that violate privacy laws, not to mention the impact on your reputation. If an email contains personal information, documents, or data that could harm your business if it was intercepted or tampered with in transit, it should be sent securely.

In sectors such as the financial services, regulators also require confirmation of delivery, making identity authentication an important feature for secure email solutions when it comes to compliance.

Industry focus: financial services

Our latest research on users of secure email indicates the types of document regularly protected using our Mailock solution. The survey, conducted primarily with professionals working in the UK financial services, found:

  • 45% regularly protect anti-money-laundering documents
  • 61% regularly protect proposal and policy documents
  • 42% regularly protect investment valuations
  • 50% regularly protect banking details

Financial services usage of secure email by type of doument

What's the best secure email solution?

When you're looking at protection for outbound emails, there are two key elements to consider regarding security: encryption strength and authentication types.

Many email providers use TLS (transport layer security). Others use PGP (pretty good privacy). These are both forms of encryption. However, they are no longer considered completely secure due to vulnerabilities and a lack of protection for emails at rest. For truly secure email, messages must be secured with at least AES-256 end-to-end encryption.

Depending on the level of security and flexibility you need, you should also be mindful of authentication types. Do you want recipients to authenticate themselves with an SMS code or a fingerprint? Each of these has pros and cons in terms of ease-of-use and security.

Further reading

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