In one embodiment, a method includes receiving, at a tracking server from a user device, a hash value associated with a tracking device. The hash value is computed based on at least a unique identifying value associated with the tracking device. The hash value is configured to expire after a predetermined period of time. The method includes determining that the received hash value is not expired. The method includes identifying the tracking device based on a comparison between a stored hash value and the received hash value. The method includes updating one or more records stored in a database accessible to, and maintained by, the tracking server that are associated with the identified tracking device based on the received hash value.