Ruleset for operator name display
RULESET FOR OPERATOR DISPLAY
The ruleset for network name display is:
1) If the Mobile Country Code (MCC) and Mobile Network Code (MNC) from the cell site match the MCC and MNC on the SIM, the Service Provider Name on the SIM is used (e.g. this would be the case with an old Omnipoint SIM in New Jersey).
2) If the MCC-MNC combination does not match, the phone checks a table in its firmware for an entry corresponding to the MCC and MNC received. If found, the network name from that entry is displayed.
3)If no table entry is found, the country abberviation (or the MCC if no country name entry is found in firmware) and the MNC are displayed.
There are somewhat different rules if both phone and SIM support EONS, which appears to allow the Service Provider Name on the SIM to be mapped to multiple MCC-MNCs.
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