Mastering Dual Encryption with Bluemetrix

Like other modern advancements in data protection, dual encryption is rooted in a central and broader goal of DORA and similar regulations: to enhance the security, privacy, and resilience of data across the financial ecosystem. While most regulations – including DORA, GLBA, PCI DSS, and FFIEC – do not explicitly require dual encryption, many financial institutions see it as a practical enhancement to meet the regulation’s security expectations.

Yet, like many data initiatives, implementation is often far more complex in practice than it appears on paper. In this blog, we’ll break down the idea of dual encryption and share Bluemetrix’s approaches needed for a secure and streamlined implementation.

Breaking Down Dual Encryption

The concept of Dual encryption, also known as double encryption, is a cryptographic technique that protects data by encrypting it twice using two separate encryption algorithms or keys. Its defense-in-depth model makes unauthorised access significantly more difficult, even if one encryption layer is compromised, the data remains protected by the second, adding an extra level of security that many financial institutions now see as essential for safeguarding highly critical and sensitive data.

Dual encryption is centred around 3 steps, each necessary in order to safeguard critical data against increasingly sophisticated cyber threats.

1. The first layer. The original data (known as plaintext) is encrypted using a symmetric algorithm such as AES (Advanced Encryption Standard). This transforms the data into ciphertext, a scrambled, unreadable format.

2. The second layer. The ciphertext from the first layer is then encrypted again, either with different encryption algorithms i.e. RSA an asymmetric algorithm, or with the same algorithm using a different key.

3. Decryption. To retrieve the original data, the user must decrypt the data in the reverse sequence by first removing the second encryption layer using the appropriate key or algorithm and then decrypting the original ciphertext using the first key.

The Importance of Dual Encryption in Modern Finance

With the rising complexity of financial systems and the tightening regulatory demands, where resilience and confidentiality are non-negotiable, many institutions are voluntarily turning to dual encryption. The National Security Agency (NSA) notes that "in some high-assurance systems, the use of two separate cryptographic modules is a requirement for certain types of classified data", while NIST discourages "relying on a single point of failure", both reinforcing its necessity in high stakes environments.

To understand how this translates in a financial setting, consider a high-risk wire transfer that requires dual authorisation. For example, one from a front-office trader and another from a senior treasury officer. Each approval comes from a separate system with different credentials and controls. If either approval is missing, the transaction doesn't go through. This mirrors how dual encryption works when data is encrypted in two independent layers, often using different algorithms or keys. Even if one layer is compromised, the second continues to protect the data.

From a practical, operational standpoint, dual encryption becomes especially effective when vaultless tokenization is used as one of the layers. Even if an attacker gains access to the encrypted data, it's unusable without both decryption keys. Without the complete chain of access, there's no way to interpret the original information, just as a transaction can’t be completed with only partial authorization. This layered protection is what makes dual encryption a powerful defense mechanism in DORA-aligned or broader financial IT risk management and third-party data sharing strategies.

In practical terms, this means:

• Resilience during cyber incidents. In general, dual encryption helps replace sensitive financial data with non-sensitive data. When one layer of encryption is breached, the second layer remains to protect critical data.

• Reduced breach severity. If encrypted data is exposed, the breach may be treated as a low-impact incident under most compliance reporting rules, since tokenized data is not considered a data breach.

• Greater third-party assurance. Because secure data sharing increases scrutiny on vendors and service providers, dual encryption provides added confidence during audits and compliance checks by ensuring sensitive data remains protected across environments.

A Role of Data Security Platform to Dual Encryption

Building on the principles of dual-layer protection, Bluemetrix introduces a complementary layer of encryption using SecureToken: one that is NIST and FIPS 140-3 ready for scalable data protection. Some traditional encryption methods rely on external vaults or redirection loops, but

with SecureToken, your sensitive data never leaves your environment.

In the sections below, we illustrate how SecureToken integrates into dual encryption architectures for both data at rest and data in transit.

Data At Rest

In most enterprise deployments, the first encryption layer is implemented at the storage level. For those financial services operating on Cloudera on-prem environments, this is typically handled by Ranger KMS, which applies block- or file-level encryption. In Cloudera Public Cloud, encryption is usually provided by cloud-native volume encryption or external key management services.

SecureToken applies second layer of encryption upstream– during ingestion – before data is written to disk. It encrypts the sensitive columns (e.g., customer IDs, account numbers) while preserving their format. This makes it easy to continue using the data across Spark, Hive, Impala, and other downstream tools without revealing real values. Because encryption is applied at the application or query layer in parallel with storage-level, this generates a true dual encryption structure, with both layers operating independently and transparently.

Data In Transit

For in-transit protection, most institutions rely on Transport Layer Security (TLS) 1.2 to encrypt data as it moves between services, users, or external APIs. However, TLS secures only the transport layer, but not with the data content if it’s intercepted after decryption (e.g., at a reverse proxy, logging layer, or downstream consumer).

SecureToken closes this gap by encrypting sensitive data before it leaves the originating service — such as Impala or Hive — ensuring that sensitive fields or tables are already protected before transmission begins. As the encrypted data moves from Service A to Service B (e.g., to HDPS, ADLS, or S3), TLS handles channel or network encryption, while SecureToken ensures an additional, independent layer is in place at the field level.

To learn more about how modern teams are using SecureToken to meet dual encryption objectives, check out our whitepaper for more. If you’d like to learn more about the enabling solution of Cloudera native tokenization in your compliance, request a demo from a Bluemetrix expert today.