Technologies for access control communications

A system, comprising:

• a server;
• an access control device configured to receive credential data from a mobile device presented to the access control device;
• and
• a gateway device communicatively coupled to the server and to the access control device, wherein the gateway device includes a memory having a gateway credential list stored thereon that identifies a plurality of credentials, each credential of the plurality of credentials being associated with a unique credential index, and wherein the gateway device is configured to:
• receive the credential data from the access control device;
• compare the credential data to the gateway credential list;
• transmit the unique credential index associated with the credential data to the server in response to a determination that the credential data matches a corresponding credential in the gateway credential list;
• and
• receive an access control decision associated with the credential data from the server in response to transmittal of the unique credential index.

A gateway device, comprising:

• a processor;
• and
• a memory comprising a gateway credential list and a plurality of instructions stored thereon, wherein the gateway credential list identifies a plurality of, wherein each credential of the plurality of credentials is associated with a unique credential index, and wherein execution of the plurality of instructions by the processor causes the gateway device to:
• receive, from an access control device, credential data received by the access control device from a mobile device in response to presentation of the mobile device to the access control device;
• compare the credential data to the gateway credential list;
• transmit, to a server, the unique credential index associated with the credential data in response to determining that the credential data matches a corresponding credential in the gateway credential list;
• and
• receive, from the server, an access control decision associated with the credential data in response to transmitting the unique credential index.