Home Location Register
The Home Location Register ( HLR ; German: Heimatortsregister ) is a (distributed) database and a central component of a cellular network . It is considered the home register of a mobile phone number , with each mobile station registered within a network and its associated mobile phone number being stored in the database. The mapping of each number to a visitor location register makes it possible, for example, to locate a mobile station within the network.
A failure of the HLR means that it is no longer possible to assign the respective participants. For a passively logged-in (inactive) device, the failure is initially not visible, it even supposedly remains logged into the network (via the VLR) - however, no more connections can be established and it can no longer be reached for incoming calls.
The following data is stored in the HLR:
- Semi-permanent data
- Temporary data