Encrypted data in the cloud? Be sure to control your own keys

Data encryption in the cloud is an absolute requirement these days.

By Linda Musthaler, Network World |  Security, cloud storage

September 05, 2014, 1:15 PM — This column is available in a weekly newsletter called IT Best Practices.  Click here to subscribe.  

With cloud computing there's no longer a question about whether you should encrypt data. That's a given. The question today is, who should manage and control the encryption keys?

Whether talking to an infrastructure provider like Amazon or Microsoft, or a SaaS provider, it's imperative to have the discussion about key control. The topic is more relevant than ever as more companies move regulated data into the cloud and as concerns about dataprivacy grow.

Protecting regulated data is top-of-mind in the U.S. where regulations such as PCI and HIPAA dictate that third parties not be able to access an organization's sensitive data. Even if the data is strongly encrypted, it's a compliance compromise if a cloud service provider has access to a full key that can decrypt the information without the data owner's knowledge or permission.

European countries, especially Germany and France, are more concerned with data privacy. They are troubled by the fact that U.S.-based cloud vendors can be subpoenaed by the U.S. government to provide access to specific information, even if it resides outside the United States. Last April, Microsoft was ordered to hand over a customer's emails to U.S. authorities, even though the data was held in a data center in Ireland. If Microsoft also held the data's encryption key, the vendor could be compelled to provide that to authorities as well.

When it comes to processing and storing data in the cloud, organizations need to control their own encryption keys. What's more, this ownership must be established before contracting for a cloud application or platform.

One key management and encryption company, Porticor, has an interesting way to address these issues. When we first introduced you to Porticor as a startup company in 2012, we mentioned the company uses a split-key approach to key management (seeNew key technology simplifies data encryption in the cloud). This approach has gained a lot of traction in the past two years, with a significant partnership with HP validating the notion of a "safe deposit box" for encryption keys that puts the customer in control.

Porticor provides both encryption schemes and key management technology, but it is the latter that is the distinct service offering. Porticor's Virtual Private Data (VPD) solution is a cloud-based virtual appliance. The encryption engine and the key management function are software based and hosted in the cloud, allowing the solution to become part of the cloud infrastructure for platforms (e.g., AWS, VMware, HP Cloud Services, etc.) and for SaaS offerings.

According to Porticor CEO Gilad Parann-Nissany, the company has two customer segments. One is the end user organization that is deploying its applications on AWS or a similar cloud infrastructure. The other is SaaS providers who want to offer their customers a range of encryption schemes and, most importantly, the ability for those end customers to control their own keys.

In developing its Virtual Key Management Service, Porticor followed the principle of a bank safe deposit box. When data in the cloud is encrypted, the key is split such that Porticor holds one part of the key and the customer holds the other--the master key. As with a safe deposit box, the customer can't decrypt the data without the key held by Porticor, and Porticor can't decrypt the data without access to the customer's master key. The keys must pair to provide access to the encrypted data, thus putting the user in control of the data. To further enhance security, the keys themselves are encrypted by the customer's master key.

This solution has been designed to basically snap into cloud infrastructures, so it is apparently possible to bring up secure encrypted disks in a matter of minutes and entire database systems in a matter of hours. Porticor makes extensive use of APIs and offers RESTful APIs in order to integrate with cloud systems and applications.

In addition, Porticor's solution can work on multiple levels. For example, customers can encrypt a complete database or a complete file store, and at the same time they can get granular in order to encrypt a single field of an application. Porticor's customers often use these capabilities in tandem to address a specific need. This multi-level capability is especially important for SaaS providers that want to enable users to encrypt, say, a field containing a credit card number, but not necessarily the entire database. Moreover, different encryption schemes can be applied to each element that is being encrypted; for example, order-preserving encryption will be applied to the ZIP code field.

Porticor's encryption and key management approach received quite a boost when HP selected the vendor to partner with for its own cloud-based Atalla security solution. Porticor's technology has been integrated into the HP stack to provide secure cloud encryption. An HP cloud encryption customer can now automatically store their part of the encryption key the master key directly into a FIPS Level II compliant hardware security module that is part of the Atalla security system.

The imperative for encryption for data in the cloud grows stronger every day--for security, for compliance, for privacy, and for peace of mind. Organizations that are putting their data in the cloud need options in which they control the encryption keys. Porticor's cloud-based Virtual Private Data system addresses those needs at the infrastructure level to reduce complexity while providing strong security.