[PCI DSS 3.0] 9.9.1 Maintain an up-to-date list of devices. The list should include the following:

9.9.1 Maintain an up-to-date list of devices. The list should include the following:
• Make, model of device
• Location of device (for example, the address of the site or facility where the device is located)
• Device serial number or other method of unique identification.

9.9.1.a Examine the list of devices to verify it includes:
• Make, model of device
• Location of device (for example, the address of the site or facility where the device is located)
• Device serial number or other method of unique identification.

9.9.1.b Select a sample of devices from the list and observe device locations to verify that the list is accurate and up to date.

9.9.1.c Interview personnel to verify the list of devices is updated when devices are added, relocated, decommissioned, etc.

Keeping an up-to-date list of devices helps an organization keep track of where devices are supposed to be, and quickly identify if a device is missing or lost.
The method for maintaining a list of devices may be automated (for example, a device-management system) or manual (for example, documented in electronic or paper records). For on-the-road devices, the location may include the name of the personnel to whom the device is assigned.