Carrier Identification

Devices running Android 9 can recognize subscription carrier information to provide an ID and a carrier name. Android maintains a carrier ID database, with matching rules for each carrier and its unique carrier ID. AOSP includes the content of the carrier ID database, in the file carrier_list.textpb. The unified database minimizes duplicate logic in apps that need to identify carriers and limits the exposure of carrier-identifying attributes.

To improve the coverage and accuracy of carrier identification, Android supports out-of-band and carrier ID table updates. Each update comes with a version number and is published to AOSP.

Implementation

Users who want to implement out-of-band updates can download the carrier_list.pb binary from AOSP. To view the readable format of the table, see carrier_list.textpb.

Place the carrier ID table in the /data/misc/carrierid/ data partition of the device. If the carrier ID table is newer than the existing version, the device persists the table to the carrier ID database class. The most recent information from the carrier ID database is picked up by the public methods getSimCarrierId() and getSimCarrierIdName().

Adding carrier ID information to the database

To add or update a carrier ID to the database, submit a request using the Carrier identification information form.

Your request is reviewed and if approved, the change is pushed to the AOSP code base at carrier_list.pb. You can then copy the updated list and incorporate it into your customized build.

Integrating carrier IDs with CarrierConfig

Starting from Android 10, carrier configuration supports using carrier IDs as keys to fetch carrier-specific configurations from CarrierService.

Integrating carrier IDs with CarrierConfig has the following advantages:

  • Consolidates all MCC/MNC pairs for each carrier into a single location removing duplicate or inconsistent data.
  • Creates a canonical identifier for each carrier and removes ambiguity.
  • Allows mobile virtual network operators (MVNOs) to be identified with individual IDs instead of having configurations as part of a mobile network operator (MNO).

Migrating configuration data to carrier IDs

To migrate configuration data from MCC/MNC pairs to carrier IDs, follow these steps:

  1. Group the carrier_config_mccmnc.xml files from a single carrier together. Use carrier_list.textpb as a reference to map the MCC, MNC, and MVNO information to a particular carrier.

  2. Merge the configurations into a single file.

  3. (Optional) Inherit data from MNOs. MVNOs inherit configurations from MNOs in the legacy carrier_config_mccmnc.xml file. Because carrier IDs allow all carriers including MVNOs to have a dedicated config file, it's recommended to include MNO data during migration.

  4. If the configuration for an MVNO carrier ID doesn't exist, fetch the configuration from its MNO carrier ID using getCarrierIdFromSimMccMnc.

  5. Rename the new file as carrier_config_carrierid_carrierid_carriername.xml where carrierid must correspond to a canonical_id and carriername should correspond to a carrier_name in carrier_list.textpb