Equipment Identity Register (EIR)
The EIR is a database that maintains records of mobile devices based on their IMEI (International Mobile Equipment Identity) numbers.
Functions of EIR:
-
Device Authentication:
Verifies the IMEI of a mobile device before allowing it to connect to the network. -
Maintaining Device Lists:
-
Whitelist: Devices allowed to access the network.
-
Greylist: Devices under monitoring (e.g., malfunctioning or suspicious devices).
-
Blacklist: Devices banned from the network due to theft, fraud, or other issues.
-
Home Location Register (HLR)
The HLR is a central database that stores permanent subscriber information required for authentication, call routing, and roaming. It works in coordination with the VLR (Visitor Location Register) and MSC (Mobile Switching Centre) to track and manage users.
Functions of HLR:
-
Subscriber Information Storage:
Maintains IMSI (International Mobile Subscriber Identity), MSISDN (phone number), service subscriptions, and authentication keys. -
Location Management:
Keeps track of the current location of subscribers by storing the identity of the VLR where they are currently registered. -
Authentication and Security:
Works with the AuC (Authentication Centre) to verify subscribers and prevent unauthorized access to the network.