Secure Messaging and File Sharing

How it Works: Secure Messaging with Cellcrypt

Cellcrypt provides real-time and offline secure messaging that meets the demands of high-security environments. The process involves encrypting and delivering messages, files, voice calls, and video conferencing sessions through a series of robust procedural steps, ensuring end-to-end security and compliance. Whether you’re sharing mission-critical updates or sensitive documents, Cellcrypt ensures your communications stay private, tamper-proof, and resilient—even on compromised networks.

1. Message Delivery Over TLS – But Not Reliant On It

Cellcrypt uses TLS (Transport Layer Security) to create encrypted tunnels between devices and servers. However, unlike conventional messaging apps, Cellcrypt does not rely solely on TLS. Every message is further encrypted at the application layer before transmission.

Even if TLS were to fail—or the server were compromised—your message content would remain entirely unreadable for any third party.

2. End-to-End Encryption by Default

Each message is encrypted on the sender's device and only decrypted on the recipient's device, ensuring:

• True end-to-end confidentiality. Only the sender and receiver can access the message content through their own encryption and decryption keys.

• No exposure of message content to Cellcrypt servers, administrators, or network intermediaries.

Message attachments, such as files, photos, and videos, are also encrypted end-to-end, with encryption keys shared securely and separately via the messaging protocol. The encryption process uses a decryption key to convert ciphertext back into plaintext, ensuring that sensitive information remains secure and accessible only to authorized parties.

3. Unique Encryption Per Message

For every single message and file:

• A new symmetric encryption key is generated.

• This key is used once and never reused, ensuring forward secrecy at the message level.

• Keys never leave the endpoints in plaintext and are never stored on any server.

  
  

This provides unprecedented granularity in security—a compromise of one message has no impact on any others.

4. Post-Quantum Cryptography (PQC) Built In

Cellcrypt implements post-quantum secure key exchange algorithms such as CRYSTALS-Kyber and Classic McEliece to protect messages against future quantum attacks. This ensures:

• Messages sent today remain secure, even decades from now.

• Resistance to "harvest now, decrypt later" strategies used by adversaries.

5. Metadata Minimisation

Unlike consumer-grade apps, Cellcrypt ensures that metadata is protected. The system avoids exposing:

• Message content

• Sender and recipient identities

• Timestamps and communication patterns

All metadata is either encrypted, anonymised, or stored under complete customer control—never accessible by Cellcrypt.

6. Offline Support with Secure Store-and-Forward

Recipients don't have to be online. Messages are:

• Encrypted on the sender's device

• Stored temporarily on the Cellcrypt server (also encrypted)

• Forwarded to the recipient when they come online

Stored messages auto-expire after a configurable retention period (default: 7 days), and all data is encrypted at rest.

7. Tamper Detection and Authentication

Cellcrypt uses:

• 521-bit elliptic curve digital authentication

• 128-bit Message Authentication Codes (MACs) to detect any unauthorised modification

• A cryptographic fingerprint to alert users if a contact's keys change, indicating a possible reinstallation or attack

These mechanisms protect against spoofing, tampering, and impersonation—ensuring your conversations are authentic and unaltered

As you can see, Cellcrypt’s security features are comparable to consumer encrypted messaging apps like Signal, offering advanced end-to-end encryption and privacy for all communications, but with the enhanced security, enterprise control and management needed for business / government communications.

Why It Matters

Standard messaging apps require trust in the platform. Cellcrypt removes that requirement. 

Recognized as a leader in encrypted communication for enterprises, Cellcrypt sets industry standards for security and compliance. Designed for Zero-Trust environments, Cellcrypt ensures that even if your network, server, or device is compromised, your messages remain protected.

From encrypted chat to secure file transfer—Cellcrypt messaging is built to withstand modern surveillance and future quantum threats. Cellcrypt enhances your collaborative efforts by allowing you to create group chats for private messaging and file sharing directly within the app. These features enhance productivity and facilitate secure, efficient communication within your organisation.

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Ideal for governments, enterprises, and businesses, Cellcrypt Secure Messaging meets the highest standards of confidentiality and operational security.​

Conclusion

Secure communication is a non-negotiable requirement for businesses and organizations aiming to protect sensitive data and uphold confidentiality.

By prioritizing end-to-end encryption, secure collaboration tools, and digital sovereignty, organizations can maintain complete control over their communication channels and data. These measures not only reduce the risk of data breaches and cyber threats but also ensure compliance with industry regulations and foster trust among customers and employees.

Businesses increasingly adopt encrypted messaging apps to mitigate cybersecurity risks as remote work increases, highlighting the growing importance of secure communication in modern workplaces..

As the world continues to embrace digital transformation, investing in robust secure communication solutions is essential for safeguarding the integrity and confidentiality of business operations. By doing so, organizations can confidently navigate the evolving landscape of data protection, maintain their reputation, and build lasting relationships with stakeholders through secure, reliable, and compliant communication.

Companies that implement encrypted communication can build trust with their clients and gain a competitive edge in their respective industries and the use of encrypted messaging apps, such as Cellcrypt, can save businesses significant time and money by preventing data breaches, further emphasizing their value in a competitive and security-conscious market. .