HLR information¶
HLR (Home Location Register) - mobile operator database, in which he stores information data about each connected subscriber.
HLR information - information, which is provided by a number of providers.
To use a service, customer sends query to HLR provider.
Query contains E.164 number of interest.
HLR provider responds with information data related to this number, such as:
- MCC-MNC code of operator, to which subscriber is connected
- subscriber availability status
- is subscriber in roaming or not
- cell identifier, to which subscriber has registered at the moment
- etc
HLR response content could vary depending on:
- HLR provider
- chosen tariff plan.
For example, HLR provider might request additional fee for more information in responses.
To produce a response, HLR provider might appeal to:
- directly to mobile operators
- to his local databases, in which he caches the results of previous queries
- to his local databases, which consists of replicated data from other HLR providers.
- to other HLR providers
As far as HLR information is constantly changing due to Number portability, the relevance of provided information depends on the data source chosen and on the response speed.
Also, price depends on what data source has been chosen by HLR provider.
Obviously, direct query to mobile operators will cost more than local database lookup.
Smartswitch can act both as the HLR information supplicant and the HLR information supplier (see section HLR dipping).
After response has been received from HLR supplier, Smartswitch puts it into HLR cache.