1. A device information gathering method comprising: allowing a device information gathering apparatus to transmit a packet to a randomly generated Internet Protocol (IP) address and to receive a syn-ack packet as a response; allowing the device information gathering apparatus to parse the syn-ack packet and thus to extract Transmission Control Protocol (TCP)/IP fields; allowing the device information gathering apparatus to compare the TCP/IP fields and an Operating Systems (OS) fingerprint rule, which is in JavaScript Object Notation (JSON) format, and thus to generate an OS fingerprint of the randomly generated IP address, wherein the OS fingerprint rule stores TCP/IP field value corresponding to OS and version of the OS as attribute-value pair; allowing the device information gathering apparatus to transmit a packet corresponding to the protocol of a predetermined port of the randomly generated IP address to the predetermined port and to receive traffic as a response; allowing the device information gathering apparatus to extract banner information and service information from the traffic; and allowing the device information gathering apparatus to compare the banner information and the service information with a service fingerprint rule, which is in JSON format, and thus to generate a service fingerprint of the predetermined port, wherein the service fingerprint rule stores value of the banner information and the service information corresponding to application providing service and version of the application as attribute-value pair.