is queued with the predetermined reference value set up corresponding to the queue space the packet may be referred to as a packet necessitating bcn or causing bcn bcn may be managed according to the configuration of the queue 110 when the space of the queue 110 is configured so that packets can be queued according to an initial sender of each packet bcn according to the present invention may be managed according to initial senders of the packets however in general the queue space of a queue is configured in correspondence to ports and classes of an apparatus currently processing packets therefore in general the bcn according to the present invention also is managed according to ports and classes when it is determined that bcn is necessary the bcn detection block 106 obtains the bcn information for the bcn and provides the bcn information to the bcn notification block 114 the bcn information includes information on an initial sender of a packet necessitating bcn in particular the information on the initial sender of the packet includes transmission information for transmitting a generated bcn message to the sender the transmission information may include at least one of the sender internet protocol ip address of the packet the destination ip address of the packet sender port information destination port information and class information the bcn information can be obtained from the forwarding block 102 when receiving information that bcn is necessary and the bcn information from the bcn detection block 106.