Today, many popular communication and file-sharing technologies have adopted end-to-end encryption to ensure secure data transmission for their users. But what does end-to-end encryption mean? How does end-to-end encryption differ from other forms of data protection, and why is it more secure? This blog will answer those questions.

What is end-to-end encryption (E2EE)?

End-to-end encryption (E2EE) is a secure data transfer method that focuses on protecting the exchange of data from device to device. With E2EE, data is encrypted on the sender’s device and is only ever decrypted on the recipient’s device – never in the cloud. And, because data is only encrypted and decrypted on users’ endpoints, it is called “end-to-end encryption.”

How does end-to-end encryption work?

Encryption works by scrambling data so that only someone with specific knowledge or access (often referred to as a key) can unscramble the data. With end-to-end encryption, this scrambling and unscrambling process works by using a unique cryptographic key pair – called the user’s public and private key pair – to encrypt and decrypt a message.

When someone wishes to send an email or file to a colleague, that information is encrypted on the sender’s endpoint (computer or smartphone) by downloading the colleague’s public key which is stored in the cloud. This public key can be shared with everyone. The private keys, however, are securely stored on the colleague’s device and are only available to that individual. This private key is used to decrypt the data. This encryption process establishes a secure communication channel that safeguards sensitive information.

By storing the user’s private cryptographic key on their endpoint, the keys are never available to the cloud. Since the cloud cannot access the decryption keys, it can never decrypt the data which means that criminals and nosy third parties cannot see the data either. Therefore, it offers individuals and businesses a powerful way to exchange information and store sensitive data without sacrificing privacy or security.

Example of end-to-end encryption

Alice and Bob create accounts on the system. The end-to-end encrypted system provides each with a public-private key pair, whereby their public keys are stored in the cloud, and their private keys are stored on their device.

Alice wants to send Bob an encrypted message. She uses Bob’s public key to encrypt her message to him. Then, when Bob receives the message, he uses the private key on his device to decrypt the message from Alice. When Bob wants to reply, he simply repeats the process, encrypting his message to Alice using Alice’s public key.

​​In this example, end-to-end encryption operates by encrypting the data at the sender’s endpoint and decrypting it only on the intended recipient’s device. This guarantees that the data remains confidential throughout the transmission process, making it impossible for unauthorized parties to access the information being exchanged.

How End-to-End Encryption (E2EE) Differs from Other Encryption Practices

To put end-to-end encryption’s groundbreaking approach to secure data transmission into context, it’s essential to understand current and legacy encryption practices implemented to protect communications and file sharing. Each encryption method has its own uses and limitations, which underscore the need for a more scalable and easy-to-use information-sharing model for data in transit and at rest.

  1. PGP: Pretty Good Privacy (PGP), the forerunner for end-to-end message encryption, employs a similar encryption method – referred to as asymmetric encryption – in which a sender uses a public key to encrypt messages, and the recipient uses a unique private key to decrypt the messages. This way, even if the email or file is intercepted, it remains secure as it can only be deciphered with the user’s private key. There are a few significant problems with PGP encryption. First of all, there’s no way to recreate a lost private key. In addition, the public key distribution system is decentralized and therefore difficult to scale. Lastly, device loss can lead to data loss within the PGP system.
  2. S/MIME: Another popular end-to-end encryption technique is Secure/Multipurpose Internet Mail Extensions (S/MIME). Used by the Department of Defense, S/MIME relies instead on digital certificates for encryption. Like PGP, S/MIME also uses Public Key Infrastructure (PKI) for asymmetric encryption to protect emails, meaning either a central authority or an individual can manage the public and private keys. However, S/MIME requires inefficient management overhead to update expired certificates, and it is not available to web-based email clients like Gmail.
  3. SSL/TLS: SSL/TLS is a point-to-point encryption system widely used today that ensures secure communication between a user’s device and the cloud or a webapp. While SSL/TLS is essential for securing data during transmission over the internet, it has limitations as it only ensures the security of the communication channel. This means that intermediaries, such as email or messaging service providers, could potentially have access to the unencrypted content of the messages, compromising privacy.

Although PGP, S/MIME, and SSL/TLS are popular email encryption techniques they all have notable drawbacks. The shortcomings of current and legacy encryption systems have inspired the adoption of modern end-to-end encryption as a new, better form of data security that is effective, user-friendly, and scalable.

PreVeil is an example of a new type of end-to-end encrypted communication and file-sharing. Like PGP, PreVeil uses asymmetric public and private keys to ensure that only the sender and recipient can view the data. However, unlike PGP and S/MIME, the platform manages the sharing of your public keys, so you don’t have to. In addition, with PreVeil’s end-to-end encryption model, lost keys can be recreated to avoid data loss.

How is End-to-end encryption used

Due to the superior security results and minimized attack surface, end-to-end encryption is quickly gaining traction across industries that rely on secure data exchange. Let’s look at real-world examples of end-to-end encryption in popular data exchange apps.

Messaging Apps: Securing Conversations with End-to-End Encryption

WhatsApp exemplifies how end-to-end encryption is implemented within secure messaging apps. When a user sends a message, the app encrypts the information using a unique private encryption key on the sender’s device. This encrypted message is transmitted over the internet and can only be decrypted on the receiver’s device, which possesses the corresponding private decryption key. This means that even if the message is intercepted during transmission or on the server, it remains encrypted and unreadable to anyone who needs the appropriate decryption key. WhatsApp uses end-to-end encryption to maintain the confidentiality of its users’ conversations.

Email Services: End-to-End Encryption of Sensitive Correspondence

When exchanging sensitive correspondence, email services that employ end-to-end encryption play a vital role in upholding data security and privacy. PreVeil is an excellent example of end-to-end encrypted email services. Sensitive information sent with PreVeil’s end-to-end encryption solution remains confidential throughout its journey, providing both senders and recipients peace of mind. By implementing robust encryption mechanisms at the device level and utilizing unique cryptographic keys for each user, PreVeil offers its users a solution for protecting sensitive emails from unauthorized access, data breaches, and surveillance. PreVeil’s rigorous end-to-end encryption email and file sharing solution supports compliance with data protection regulations across industries, including CMMC, ITAR, HIPAA, and more.

What are the advantages of end-to-end encryption

End-to-end encryption provides several crucial benefits that make it a powerful tool for data security, protecting against various threats and facilitating compliance with regulatory standards such as ITAR (International Traffic in Arms Regulations) and CMMC (Cybersecurity Maturity Model Certification).

Protection in Transit:

One of the primary advantages of end-to-end encryption is its ability to provide robust security during data transmission. End-to-end encryption significantly reduces vulnerability to unauthorized access or interception of data during transit by encrypting data at the sender’s device and decrypting it only at the recipient’s device. This allows for the confidentiality of sensitive information, even if it passes through unsecured or potentially compromised networks.

Data Integrity and Tamper-Resistance:

End-to-end encryption protects data from unauthorized access and ensures data integrity. As a result of the underlying cryptographic techniques, end-to-end encryption protects against tampering attempts or modifications to the encrypted data during transit. These cryptographic techniques, such as digital signatures and message authentication codes, use mathematical algorithms to ensure that the data remains unchanged and can be trusted by the recipient. By employing cryptographic techniques, end-to-end encryption guarantees the authenticity and reliability of the data exchanged.

Support for Compliance with ITAR and CMMC:

Compliance with regulations such as ITAR and CMMC is critical for organizations handling sensitive State Department or DoD information. End-to-end encryption plays a significant role in meeting these compliance requirements. It ensures that sensitive data, including export-controlled technical data and personally identifiable information (PII), is protected from unauthorized disclosure. By implementing end-to-end encryption, organizations can strengthen their overall cybersecurity posture and demonstrate compliance with these regulatory standards.

Limitations of End-to-End Encryption

While end-to-end encryption is widely regarded as one of the most secure methods to protect data, it is essential to understand its limitations and challenges. Here are three key aspects to consider:

  • Limited Accessibility for Law Enforcement: One of the main challenges of end-to-end encryption is that it prevents anyone, including law enforcement agencies, from accessing the encrypted data stored on servers or transmitted over networks. While this aspect ensures the privacy and security of individuals’ data, it can create difficulties for law enforcement investigations that rely on accessing and analyzing digital evidence. Striking a balance between privacy and the needs of law enforcement to investigate potential threats remains an ongoing challenge.
  • Vulnerability to Compromised Endpoints: End-to-end encryption relies on the endpoints’ security — the devices used by the sender and recipient — to encrypt and decrypt the data. If either endpoint is compromised through malware, hacking, or physical access, it can undermine the effectiveness of end-to-end encryption. Attackers may gain unauthorized access to decrypted data or intercept information before it gets encrypted. Ensuring the security of endpoints becomes crucial to maintaining the integrity and confidentiality of data.
  • Insecurity of Metadata: Another limitation of end-to-end encryption is that while it protects the content of the communication, it does not secure the associated metadata used to manage the system. Metadata includes information about the sender, recipient, timestamps, and other contextual data often considered valuable for analysis and tracking. Although the message contents remain encrypted, metadata can still provide important insights, such as patterns, frequency, or connections between individuals. Protecting metadata can be challenging as it often needs to be shared to enable communication, raising concerns about comprehensive privacy protection.

Understanding and addressing these challenges are essential for organizations and individuals seeking to effectively leverage the security benefits of end-to-end encryption. While it provides robust protection for data, it is crucial to evaluate these limitations and implement additional security measures where necessary to mitigate risks and maintain a comprehensive data security strategy.

End-to-End Encryption (E2EE) with PreVeil

PreVeil utilizes E2EE to provide a leading product in secure email communication and file sharing. Designed to focus on data privacy and security, PreVeil encrypts messages and attachments on the sender’s device and decrypts them only on the recipient’s device. This approach ensures that emails and files remain fully protected throughout transit and storage, safeguarding sensitive information from unauthorized access and interception.

PreVeil prioritizes compliance with regulations like ITAR and CMMC, making it an ideal choice for organizations handling sensitive government or military information. By embracing end-to-end encryption, PreVeil empowers organizations to maintain the confidentiality and integrity of their communications and data.

Learn more about how PreVeil uses end-to-end encryption to protect your data. Download our architectural whitepaper today.

Frequently Asked Questions

Can end-to-end encryption be hacked?

While hacking e2ee is possible, it is unlikely. First of all, hackers usually focus on attacking servers rather than endpoints and with e2ee, all data on the server is encrypted and hackers do not have the decryption keys. Similarly, if hackers attack the data in transit, they still don’t have the decryption keys. Lastly, attackers will often compromise a credential so it can be used in a remote attack. However, in e2ee systems, the attacker has no keys and cannot attack remotely.

Does end-to-end encryption have a backdoor?

A backdoor is a way for someone to bypass an encryption method’s normal security measures. With end-to-end encryption, a backdoor would be a way for someone to get access to a user’s private key. This type of access could be provided if the security provider keeps a copy of the private keys on a key server. While some e2ee providers have adopted this type of backdoor, PreVeil has not. At PreVeil, the only person who has a copy of the private key is the owner of the account.