IP addresses were never intended as a means to identify a physical location, but over time several ancillary technologies and processes have made this possible. Many services provide physical location based on IP address but they do so by aggregating many different data points, including:
- Autonomous System Numbers (ASN) assigned by the Internet Assigned Numbers Authority (IANA)
- IP hierarchies from a Regional Internet Registry (RIR), National Internet Registry (NIR), or a Local Internet Registry (LIR)
- Internet Service Provider (ISP) IP information
- Named host and node details
- Self-reported information
These pieces of information are combined with other details that may be known, such as the physical address of a company office or data center, to provide reasonably accurate location details. However, it is very easy to fool such a system accidentally or intentionally. For example, if you update your Facebook status from the on-board WiFi on a Delta Airlines flight it will likely say that you are at Hartsfield-Jackson International Airport in Atlanta, Georgia as this is Delta's home base and the location most associated with the IP address of the plane or network you are on.