Patent ID: 7120171

Claim:
A packet data processing apparatus for processing a packet data stream received through a packet-switched network, wherein: said packet data processing apparatus comprises: a network interface unit for receiving packet data constituting said packet data stream from said packet-switched network; a buffer for temporarily storing said packets received by said network interface unit; a processing unit for sequentially reading and processing the packet data stored in said buffer; and a monitoring unit for monitoring a state of said buffer periodically; and said monitoring unit comprises: an underflow or overflow processing part which periodically judges whether the buffer is in a state of underflow or overflow, and if the buffer is in the state of underflow or overflow, performs a process to have an amount of data stored in the buffer to be equivalent to a predetermined amount for absorbing transmission fluctuation, and a synchronous processing part which makes said processing unit skip at least one packet data to be read and processed next by said processing unit, if a number of the packet data stored in said buffer shows a tendency of increasing from a predetermined number of packet data, successively a given number of times; and which makes said processing unit suspend operation during a period of time required for reading and processing at least one packet data, if the number of the packet data stored in said buffer shows a tendency of decreasing from the predetermined number of packet data, successively the given number of times.