Network system using WSD protocol, comprising plurality of devices capable of changeover between representative device and non-representative device, and management method therefor

A network system using a WSD protocol, comprising a plurality of devices capable of changeover between a representative device and a non-representative device, wherein the representative device comprises:

• a command transmitting unit that transmits a command for requesting information required by the representative device for network management from the non-representative device, when the non-representative device has joined a network or when there is a change in a state of the non-representative device;
• a command receiving unit that receives a command including the information sent from the non-representative device that has received the command;
• a management unit that manages the information received by the command receiving unit as device management information;
• a representative device selecting unit that selects a next representative device using the device management information when representative device functions of the representative device are to be disabled;
• an inheritance information generating unit that generates inheritance information for delegating authority as the representative device and inheriting the device management information;
• and
• an authority inheriting command transmitting unit that sends the inheritance information to the next representative device,
• wherein the representative device selecting unit selects one of:
• a non-representative device from which the command receiving unit received the command at the oldest time in the device management information, a non-representative device that has the least used frequency in the device management information, and a non-representative device that has the highest performance in the device management information, as the next representative device, and
• wherein upon receiving the authority inheriting command, the non-representative device rewrites itself to the representative device, and notifies other devices on the network that it has become the representative device, using the command transmitting unit.