Link selector in a modular physical access control system

A device comprising:

• a memory storing instructions;
• and
• a processor configured to execute the instructions to:
• receive an instruction from an administration device;
• identify a link selector in the instruction, wherein the link selector corresponds to an attribute of a first domain object that specifies how a target resource of a second domain is to be controlled by the first domain object;
• query a database of contracts to determine that target resource is able to fulfill the contract, based on contracts associated with the target resource;
• generate a resource contract between the first domain object and the target resource of the second domain object, based on determining that the target resource is available to be controlled by the first domain object, wherein the resource contract indicates the target resource of the second domain object is controlled by the first domain object;
• and
• enable the first domain object to communicate with the target resource of the second domain object in accordance with the generated resource contract.

A non-transitory computer-readable memory device storing instructions executable by a processor, the non-transitory computer-readable memory device comprising:

• one or more instruction to receive an instruction from an administration device;
• one or more instruction to identify a link selector in the instruction, wherein the link selector corresponds to an attribute of a first domain object that specifies how a target resource of a second domain is to be controlled by the first domain object;
• one or more instruction to query a database of contracts to determine that target resource is able to fulfill the contract, based on contracts associated with the target resource;
• one or more instruction to generate a resource contract between the first domain object and the target resource of the second domain object, based on determining that the target resource is available to be controlled by the first domain object, wherein the resource contract indicates the target resource of the second domain object is controlled by the first domain object;
• and
• one or more instruction to enable the first domain object to communicate with the target resource of the second domain object in accordance with the generated resource contract.