Communication apparatus

A communication apparatus for controlling communication between an own area, to which the communication apparatus belongs and to which a level is assigned, and another area, to which a different level from the level of the own area is assigned, in a hierarchical network including areas to which levels are assigned, the communication apparatus comprising:

• a link-information storage unit that stores therein link information indicating a network connection status across the hierarchical network;
• a link-information transmitting unit that transmits collected link information of the own area indicating a network connection status in the own area to another area assigned a different level from the level assigned to the own area, the collected link information being collected in certain cycles;
• a link-information determining unit that determines, when receiving link information from another area assigned the different level, whether received link information is new link information that is newer than link information stored by the link-information storage unit;
• and
• a link-information advertising unit that stores new link information into the link-information storage unit and advertises the new link information in the own area when the link-information determining unit determines that the received link information is the new link-information, and discards the received link information without storing and advertising the received link information, when the link-information determining unit determines that the received link information is not the new link-information.