Electronic mail is likely one of the most handy communication channels for companies and people, because of its accessibility. However this additionally makes e mail inclined to cybercriminals who try to entry delicate knowledge by intercepting emails in transit or hacking into e mail servers.
One of many predominant traces of protection in opposition to this assault is e mail encryption, a extensively used solution to safe the knowledge despatched over e mail.
Now, you in all probability have a flurry of questions on this matter, like:
- What’s e mail encryption?
- How do encrypted emails work?
- Why do you have to encrypt emails?
Learn on to search out the solutions to those and different frequent questions on encryption and find out how Twilio SendGrid secures emails in transit.
What’s e mail encryption?
At the beginning, e mail encryption scrambles the content material of an e mail, changing it into an unreadable format referred to as ciphertext. As soon as an e mail is encrypted, solely a licensed consumer (the recipient) can decrypt it and consider the unique message. Anybody else who tries to intercept the message will solely have the ability to see the ciphertext—thus, defending the contents of the e-mail.
How does e mail encryption work?
Electronic mail encryption makes use of cryptographic keys or strings of characters that substitute the unique knowledge to seem random. And in contrast to the easy cryptographic keys that individuals can create, e mail encryption providers generate keys utilizing complicated algorithms that scramble the info past human recognition.
So how do senders and recipients use these keys to encrypt and decrypt messages? There are 2 methods:
- Symmetric cryptography: The sender and the recipient use a single, non-public key to encrypt and decrypt the message. This implies the sender must share the important thing with the recipient to allow them to decrypt the message.
- Uneven cryptography: The sender makes use of a public key to encrypt the message, then the recipient makes use of a personal key (that solely they know) to decrypt it. That is also referred to as public-key cryptography, and in contrast to symmetric encryption, the sender and recipient don’t have to share the important thing.
Nonetheless, right this moment, probably the most extensively used varieties of encryption are inclined to depend on a mixture of symmetric and uneven cryptography, as we’ll focus on later.
Why ought to senders encrypt emails?
Earlier than we reply that, let’s begin with a reminder that you must by no means ship delicate data, like passwords or Social Safety numbers, over e mail.
That mentioned, emails typically comprise private details about the recipient, like their tackle, or enterprise data not supposed for the general public. And with out encryption, dangerous actors might intercept that data and use it to commit id theft, fraud, and different crimes in opposition to people or companies.
This is the reason encryption is so necessary: it ensures that no particular person or entity intercepts the content material of the e-mail alongside the best way or, in some instances, because it sits in e mail servers.
Moreover, attributable to legal guidelines just like the Normal Knowledge Safety Laws, regulators can tremendous companies if prospects’ private knowledge is compromised. Nonetheless, encryption can assist keep away from this.
Lastly, encryption is a vital component of e mail safety that may in the end affect the sender’s repute and deliverability.
What are the various kinds of e mail encryption?
There are 3 frequent varieties of e mail encryption used right this moment. Let’s have a look at how these work, plus a safe different for sending extremely delicate data.
TLS
Transport layer safety (TLS) is a protocol that encrypts e mail knowledge because it travels from the sender’s e mail server to the recipient’s—although it doesn’t encrypt it at its vacation spot. TLS makes use of uneven and symmetric cryptography to encrypt e mail knowledge. Meaning it generates and exchanges a session key by means of uneven cryptography, then the sender and recipient use this key to encrypt and decrypt the message.
Many e mail suppliers, together with SendGrid, use opportunistic TLS encryption by default (extra on this beneath). This prevents cybercriminals from studying the contents of an e mail whereas it’s in transit, generally known as a man-in-the-middle assault.
Most net servers additionally use TLS for safe searching—you may acknowledge it because the lock image on an internet browser while you’re on a safe web site. The sort of encryption replaces its predecessor, Safe Sockets Layer (SSL).
Subsequent, we’ll have a look at varieties of encryption that safe knowledge on the server.
PGP
Fairly Good Privateness (PGP) was the primary profitable implementation of a public-key encryption resolution for e mail.
Within the easiest phrases, PGP encryption works by producing a random session key that the sender encrypts utilizing the recipient’s public key. The sender then shares the encrypted session key with the recipient, who can decrypt it with their non-public key. Lastly, the recipient makes use of this session key to decrypt the message.
PGP encryption protects knowledge because it travels and on the server. This is called data-at-rest encryption or end-to-end e mail encryption, and it means solely the supposed recipient can decrypt the message. Thus, it protects delicate data from cybercriminals who may goal your e mail server.
To make use of PGP encryption, customers usually have to obtain an add-on—suppliers like Outlook, Apple, and Thunderbird have PGP add-ons obtainable. Nonetheless, the sender and recipient should each set up the add-ons and allow PGP encryption to ship safe messages.
S/MIME
Safe/Multipurpose Web Mail Extensions (S/MIME) is a extensively used protocol for sending encrypted messages with a digital signature. Like PGP, S/MIME supplies end-to-end encryption, securing messages in transit and on the e-mail server.
This protocol additionally allows the sender to digitally signal the message, authenticating their id and the integrity of the info they ship. So it offers the recipient peace of thoughts that the message comes from a official sender and nobody intercepted or altered the content material alongside the best way.
S/MIME additionally makes use of uneven encryption, requiring public keys from a certificates authority. This implies the sender makes use of the recipient’s public key to encrypt the message, then the recipient decrypts it with their non-public key. Moreover, the sender makes use of their non-public key to digitally signal the message.
Most main e mail suppliers—together with Microsoft (Alternate and Outlook), Google, and Apple—assist S/MIME encryption by means of plugins. Nonetheless, each the sender and the recipient have to allow S/MIME encryption to ship safe messages. Moreover, directors can arrange S/MIME encryption for all the e-mail customers of their group.
Internet portal
Internet portals are a safe different to make use of when you must share extremely delicate knowledge, resembling protected well being data or monetary data, because it’s greatest to not ship that data over e mail. Not solely is it not well worth the threat of compromising the recipient’s knowledge, however rules just like the Well being Insurance coverage Portability and Accountability Act (HIPAA) typically prohibit it.
With this methodology, the sender notifies the recipient through e mail that they’ve a brand new encrypted message. The recipient should then log into the safe portal to retrieve the message. This fashion, you possibly can nonetheless benefit from the comfort of speaking over e mail whereas defending the recipient’s knowledge and complying with rules like HIPAA.
Safe emails in transit with Twilio SendGrid
Wish to know the way Twilio SendGrid secures your messages? By default, SendGrid makes use of opportunistic TLS encryption for outbound emails. This implies we try to ship e mail over a TLS-encrypted connection so long as the recipient’s server accepts an inbound TLSv1.1 or larger connection. Nonetheless, if the recipient’s server doesn’t assist TLS, we ship the message unencrypted.
You may as well go for the enforced TLS setting, which lets you specify the recipient has to assist TLS. Nonetheless, in case you select to implement TLS and the recipient’s inbox supplier doesn’t settle for the TLS encryption, we received’t ship the message. You’ll see this as a block occasion with the outline “TLS required however not supported.”
Now that you’ve got a greater understanding of e mail encryption, be taught extra concerning the different e mail safety elements that affect sender repute and deliverability in our 2022 Electronic mail Deliverability Information.
Or in case you’re prepared to start out sending safe emails with SendGrid, join free right this moment.
