A network node for detecting a communication device in a local network and identifying a type of the detected communication device, comprising: a detecting unit that detects a search message sent out by a communication device in the local network, the search message including an indicator of a target node to be searched for; a generating unit that generates a response message upon detection of the search message, the response message including a network address at which the communication device can access the network node and an indicator of the target node; a sending unit that sends the response message to the communication device as a response to the search message; a receiving unit that receives a request message addressed to the network address from the communication device, the request message including identification information which corresponds to a type of the communication device; an extracting unit that extracts the identification information from the request message; and a reporting unit that reports the identification information to an identifying unit that identifies the type of the communication device based on the identification information, characterized by that: the request message further includes unique information which distinguishes the communication device from another communication device; the extracting unit extracts, from the request message, the_ unique information in addition to the identification information; the reporting unit reports, to the identifying unit, the unique information in association with the identifying information; and the identifying unit is configured to identify the type of the communication device by searching a database for a type which is associated with the identification information, and the identifying unit is further configured to, if two or more types which are associated with the identification information is found by the searching, identify the type of the communication device by searching the database for a type which is associated with both the identification information and another identification information reported by the reporting unit in association with the unique information. a detecting unit that detects a search message sent out by a communication device in the local network, the search message including an indicator of a target node to be searched for; a generating unit that generates a response message upon detection of the search message, the response message including a network address at which the communication device can access the network node and an indicator of the target node; a sending unit that sends the response message to the communication device as a response to the search message; a receiving unit that receives a request message addressed to the network address from the communication device, the request message including identification information which corresponds to a type of the communication device; an extracting unit that extracts the identification information from the request message; and a reporting unit that reports the identification information to an identifying unit that identifies the type of the communication device based on the identification information, characterized by that: the request message further includes unique information which distinguishes the communication device from another communication device; the extracting unit extracts, from the request message, the_ unique information in addition to the identification information; the reporting unit reports, to the identifying unit, the unique information in association with the identifying information; and the identifying unit is configured to identify the type of the communication device by searching a database for a type which is associated with the identification information, and the identifying unit is further configured to, if two or more types which are associated with the identification information is found by the searching, identify the type of the communication device by searching the database for a type which is associated with both the identification information and another identification information reported by the reporting unit in association with the unique information. the request message further includes unique information which distinguishes the communication device from another communication device; the extracting unit extracts, from the request message, the_ unique information in addition to the identification information; the reporting unit reports, to the identifying unit, the unique information in association with the identifying information; and the identifying unit is configured to identify the type of the communication device by searching a database for a type which is associated with the identification information, and the identifying unit is further configured to, if two or more types which are associated with the identification information is found by the searching, identify the type of the communication device by searching the database for a type which is associated with both the identification information and another identification information reported by the reporting unit in association with the unique information.