Homomorphic Key Management

Protecting Your Keys Everywhere They Go

Porticor Virtual Key Management™ is the only solution that keeps your encryption keys safe at all times – even when they are in use in the cloud. The heart of Porticor’s key management system is the Master Key. Only you, the customer, hold the master key to your application, and without it, nobody can penetrate your encrypted data.

To guarantee the safety of your master key at all times, Porticor uses a powerful cryptographic technique called partially homomorphic encryption to protect the key while it is in use. Even if the key is hacked or stolen, it cannot be used by anybody but you.

What is Homomorphic Encryption?

Homomorphic encryption is a technique that enables mathematical operations to be performed on encrypted data. Porticor has developed a patent-pending technology that implements homomorphic techniques for combining and splitting encryption keys. It enables the Porticor Virtual Appliance to give the application access to the data store without ever exposing the master keys in an unencrypted state. It also ensures that if a master key is stolen, it can still never be used to access your data store.

How it Works

With Porticor, each data object (such as a disk) is stored in a Porticor Virtual Appliance and is encrypted using split-key encryption. Each key has two parts:

  • The first part, the Master Key, is retained by the application owner (you) and is never stored in open form in either your cloud account, or on the Porticor Key Management Server.
  • The second part, the project key, is stored on the Porticor Key Management Service

When the application needs to access the data store, the Porticor Virtual Appliance combines both parts of the key in a mathematical operation. Ordinarily, this would require both parts of the key to be exposed. However with Porticor, both parts of the key are encrypted before and during the startup of the virtual appliance. As a result, the keys are fully encrypted when they are resident in in your cloud account. Furthermore, Porticor encrypts the keys differently for every legitimate use. So even if your encrypted master key is stolen, it can never be used to access your data.

Ensuring High Performance

With Fully Homomorphic Encryption, all mathematical operations can be performed on encrypted data, but since it requires an enormous amount of computational resources, it isn’t yet feasible for a real-world system. With Partially Homomorphic Encryption, only select mathematical operations are supported, dramatically reducing the computational overhead. Porticor has developed a patent-pending implementation of Partially Homomorphic Encryption so that the most critical link in the encryption of data in the cloud – the keys – is also encrypted and secure. At the same time, you benefit from fast, reliable performance for your business-critical applications.

Understanding threats in the cloud and the benefits of Homomorphic Key Management

In order to manage and mitigate risk, you need to understand it. Threats to cloud security are widely publicized and they are real; but with Porticor, you get a level of data protection that is unavailable even in on-premise encryption solutions.

All data encryption systems, both in the cloud or in a physical data center, share a common vulnerability – they need to use the encryption keys. When the keys are in use, they can, in theory, be stolen. Porticor takes every known precaution, and has invented several new ones to mitigate this risk.

Porticor appliances are designed for security. The disks never contain the encryption keys and the memory is totally inaccessible – even to Porticor – without audited customer permission. Nevertheless, in the highly unlikely event that an appliance is breached and the encryption key is stolen, only the one data object that is in memory at that time is exposed. In order to access the rest of your data storage, the thief would need your Master Key. Thanks to homomorphic key management, your Master Key can never be stolen and used. As a result, the breach of a single object cannot lead to a breach of your entire system. This is a level of protection that even on-premise encryption solutions cannot offer. For a (highly technical, mathematical) analysis and proof of the strength of the approach, see here.