Google has opened the doors to one of its data centers to show how it protects customer data in this report from silicon.com.
A video released by Google on YouTube shows how it guards its data centers using a range of security measures - from biometric IDs for staff to the complete destruction of defunct hard drives.
Google's data centers handle information relating to everything from a search on Google.com to an e-commerce transaction through Google Checkout.
The security process starts with the design of Google's servers - with the machines custom-built to Google's specifications and running a specialized, stripped-down version of the Linux OS.
Google claims that the customized hardware and software limits the vulnerabilities of the machines.
Photo credit: Google/YouTube.com
Google staff have to go through a series of identity checks to gain access to the data center building and different parts of the facility.
Staff at the datacenters carry identity badges that are made using lenticular printing, which makes them difficult to forge.
In some of Google's datacenters, staff identity is checked by scanning their irises, as seen here.
Photo credit: Google/YouTube.com
Google takes a variety of steps to protect customer data stored on its data center hard drives, a rack of which are seen here.
Customer data is stored in multiple locations, the files that store the data are given random file names and are not written in clear text, so they are not easily readable by people.
If there is a fire or any other disruption at the data center, customers are able to access their data from another data center location.
Photo credit: Google/YouTube.com
Google tracks the location and status of each hard drive in its data centers.
If there is a problem with a hard drive, it's reformatted and retested. If the drive does not pass these tests it's then removed, and the data on the drive is overwritten and verified to make sure it contains no customer data.
Photo credit: Google/YouTube.com
Drives that are no longer in use at the datacenter are destroyed in a multistep process to ensure that the data they contained is not recoverable.
The first step is putting drives into the crusher, where a steel piston is pushed through the drive deforming the drive's platters and making them unreadable.
Photo credit: Google/YouTube.com
The next stage of the destruction process is putting the drives through a shredder that reduces the drives into fragments.
Photo credit: Google/YouTube.com
Information stored on hard drives inside the data centers is also backed up on magnetic tapes, such as the banks of tapes seen here.
Photo credit: Google/YouTube.com
Video surveillance allows Google staff to monitor datacenters, with the help of video analytics software that can detect anomalies in the video and tip off security staff.
Some data centers also have thermal imaging cameras to identify the heat signature of potential intruders.
Photo credit: Google/YouTube.com
Each data center has emergency back-up generators, which are capable of powering the data centers in the event of a power failure.
Data centers are connected to the internet via high-speed fibre optic cable, with multiple redundant connections to provide access to the data center in the event of the failure of a single connection.
Photo credit: Google/YouTube.com