http://www.youtube.com/watch?feature=player_embedded&v=qxZO-0wMcEc Cloud storage for businesses has emerged as something of a contentious issue among IT administrators and security professionals. Employees have taken to using consumer-centric services such as Dropbox and Box.com to transfer work materials to and from the cloud, raising issues related to everything from encryption to privacy regulations. SpiderOak aims to quiet some of those enterprise-related concerns with its SpiderOak Blue Private Cloud, which allows users to keep encrypted data in an onsite private cloud, hidden from outsiders’ private eyes. It seems like an evolution on SpiderOak Blue, announced in April, which allowed companies to store data in SpiderOak’s cloud. SpiderOak’s products are built on what it calls a “zero knowledge” system of storing data within the cloud. “Let’s say you have a computer,” SpiderOak CEO Ethan Oberman explained in a rather helpful video posted on the company’s Website (and embedded above). “You upload that data into SpiderOak. The way we did this is, this data is actually encrypted locally on your machine, and the only thing SpiderOak sees is a bunch of encrypted data blocks in ones and zeros.” That data is uploaded and stored on SpiderOak’s servers in its encrypted format; it stays encrypted when the time comes to download the data. “This is a complete zero-knowledge privacy environment,” Oberman said, adding that data is only decrypted on machines belonging to the user. SpiderOak Blue Private Cloud lets companies bring that “zero knowledge” encryption model behind the corporate firewall, with all data remaining in the onsite cloud. Clients have a choice of deploying SpiderOak Blue Private Cloud on either the latter’s hardware or their own. Additional features include “easy” internal and external sharing, sync and backup functionality, unlimited computer connections, single sign-on, and administrative data viewing and restore. The use of a private cloud may raise scalability questions that don’t usually come into play with public clouds. For companies with a powerful need to lock down their data as much as possible, however, something like a “zero knowledge” system could prove very attractive.