Server and method for controlling external device

A server for controlling an external device, the server comprising:

• a communicator;
• a memory configured to store at least one natural language understanding (NLU) engine, which generates a command corresponding to a user's utterance;
• and
• a processor configured to:
• control the communicator to receive, via a first communication, from a pairing device paired to the external device, the user's utterance to control the external device and information about at least one external device registered with the pairing device,
• identify an NLU engine corresponding to the external device, from among the at least one NLU engine, based on the user's utterance and the information about the at least one external device, and
• provide the command controlling the external device based on the user's utterance, using the identified NLU engine,
• wherein the processor is further configured to:
• identify whether the external device is paired to the pairing device via a second communication,
• based on the external device being paired to the pairing device via the second communication, control the communicator to transmit an information corresponding to the external device and the provided command to the pairing device via the first communication, and
• based on the external device not being paired to the pairing device via the second communication, control the communicator to directly transmit the provided command to the external device via a third communication.