Abstract: A switching apparatus for learning a source address set in a packet in an address learning table and delivering a packet on the basis of an address learned in the address learning table includes an address learning unit for limiting a number of learned addresses such that a number of learned addresses for each user group in the address learning table is equal to or less than an address learning upper limit value for the user group.

Abstract: A bridge apparatus is provided, which apparatus includes a tag attaching mechanism for attaching a plurality of VLAN tags to a frame, a queue configured to store the frame according to the VLAN tags attached thereto, and a read control unit configured to control a read rate for reading the frame from the queue. The VLAN tags are stacked, and a first VLAN tag of the stacked VLAN tags is used for user identification, and a second VLAN tag of the stacked VLAN tags is used for base location route identification. Also, band control is conducted based on the VLAN tags.

Abstract: A packet switching device for receiving and forwarding a packet, comprises a counter for indicating a storage capacity of specified packets in stored packets, and means for starting a forwarding restriction of the specified packets if the counter exceeds a preset forwarding restriction start threshold value. The forwarding restriction is a process of, e.g., lowering a priority of the specified packets in the received packets. The packet switching device further comprises means for canceling the forwarding restriction when the counter becomes smaller than a preset forwarding restriction terminating threshold value.

Abstract: A switching apparatus for learning a source address set in a packet in an address learning table and delivering a packet on the basis of an address learned in the address learning table includes an address learning unit for limiting a number of learned addresses such that a number of learned addresses for each user group in the address learning table is equal to or less than an address learning upper limit value for the user group.