Blocking network access for unauthorized mobile devices

A system comprising:

• one or more servers, including a memory and a processor and associated with a first network, to:
• receive one or more identifiers associated with respective user devices of the first network;
• store the one or more identifiers;
• receive a query from a network device associated with a second network,
• the query including a request for information to identify whether a user device is authorized to access the second network,
• the first network being associated with a network that services a geographic region associated with the user device, and
• the query being transmitted based on an identifier associated with the user device;
• determine the identifier associated with the user device;
• determine whether the identifier matches one of the stored one or more identifiers;
• determine that the user device is not authorized to access the second network based on determining that the identifier matches one of the stored one or more identifiers;
• determine that the user device is authorized to access the second network based on determining that the identifier does not match one of the stored one or more identifiers;
• and
• provide, to the network device, a response to the query,
• the response to query identifying whether the user device is authorized to access the second network based on determining that the user device is not authorized to access the second network or based on determining that the user device is authorized to access the second network.

A non-transitory computer-readable medium storing instructions, the instructions comprising:

• a plurality of instructions which, when executed by one or more processors associated with a first server of a first network, cause the one or more processors to:
• receive a first query from a network device associated with a second network,
• the first query including a request for information to identify whether a user device is authorized to access the second network,
• the first network being associated with a network that services a geographic region associated with the user device, and
• the first query being transmitted to the first server based on an identifier associated with the user device;
• determine the identifier associated with the user device;
• provide, to a second server, a second query including the identifier,
• the second query including a request for information to identify whether the identifier of the user device is being stored by the second server;
• receive, from the second server, a response to the second query,
• the response to the second query identifying that the identifier of the user device is being stored by the second server;
• determine, based on the response, that the user device is not authorized to access the second network;
• provide, to the network device, a response to the first query,
• the response to the first query identifying that the user device is not authorized to access the second network, and
• the network device denying the user device access to the second network based on the response.