Patent ID: 8593997

Claim:
An apparatus, comprising: a transmitting unit configured to transmit a first group of data units, which is a sequential transmission pattern, and a second group of data units having the same message length of the first group of data units, which is a divided transmission pattern to another apparatus, wherein each data unit of said first group includes a request message for a response, and data units of said second group include divided messages, wherein the sequential transmission pattern is a pattern that will cause a collision between uplink and downlink lines and the divided transmission pattern is a pattern that will not cause a collision; a receiving unit configured to receive response messages, each of which is returned by said another apparatus in response to detecting at the another apparatus, said request message of said each data unit of said first group, and to receive divided response messages that are returned by said another apparatus in response to a detection of a message obtained by assembling the divided messages at the another apparatus; and a judging unit configured to judge that when a loss rate of the response messages received at said apparatus from said first group is smaller than a loss rate of the divided response messages received from said another apparatus, a full duplex/half duplex mismatch is determined as present on a network path between the apparatus and the another apparatus.