Patent ID: 7286539

Claim:
A packet forwarding apparatus for controlling forwarding of communication packets between each of user terminals and a management server comprising: a plurality of first interface units each accommodating an access line connected to at least one user terminal; a second interface unit connected to the management server for managing communication control information to be used in communication between the user terminals and a wide-area network; and a control unit, wherein said control unit is provided with a management table comprised of a plurality of table entries each indicating, in association with a fixed address of the user terminals, a relationship between a connection port identifier for specifying the first interface unit to which the user terminal is connected and specific header information which is dynamically assigned to the user terminal by said management server and applied to each user packet by the user terminal, and wherein said control unit judges whether new specific header information can be assigned to the user terminal by said management server based on the number of assigned specific header information associated with the fixed address of the user terminal indicated by said management table, while any of the user terminals is executing with said management server a predetermined communication protocol procedure prior to communication with said wide-area network, and discards, when it is determined that the specific header information should not be assigned to the user terminal, a packet received from the user terminal or a packet received from said management server and addressed to the user terminal.