Abstract: A communication system includes a relay device and a diagnosis target device. The relay device includes a port configured to connect a diagnostic tool. The diagnosis target device is connected to the relay device via a bus. When the diagnosis target device has received specific data whose source appears to be the diagnostic tool, the diagnosis target device sends an inquiry signal for inquiring of the relay device about a monitoring result for the specific data. The relay device determines in response to the inquiry signal whether the specific data is legitimate data from the diagnostic tool. The relay device sends the monitoring result including a determination result to the diagnosis target device.

Abstract: A processor of a vehicle monitoring device obtains log information of an event that has occurred in a vehicle on-board device, determines whether a diagnosis is necessary based on the obtained log information, and transmits a diagnostic data set to an external server when determining that a diagnosis is necessary. The diagnostic data set transmitted to the server by the processor includes log information based on which a diagnosis is determined to be necessary, log information that is obtained prior to the determination, and log information that is obtained after the determination.

Abstract: A communication system includes a relay device and a diagnosis target device. The relay device includes a port configured to connect a diagnostic tool. The diagnosis target device is connected to the relay device via a bus. The relay device determines whether a communication path of diagnostic data for diagnosing the diagnosis target device is correct when the relay deice has received the diagnostic data, the diagnostic data being data that is transferred between the relay device and the diagnostic tool. The relay device sends to the diagnosis target device a monitoring result including a determination result as to whether the communication path of the diagnostic data is correct.

Abstract: An exhaust gas purifying catalyst (10) according to the present invention is an exhaust gas purifying catalyst including the first catalyst layer (12). The first catalyst layer (12) includes the first section (14) and the second section (15) in the exhaust gas flow direction. The first section (14) is located on the upstream side in the exhaust gas flow direction relative to the second section (15). A catalyst layer (16) contains a catalytically active component including a specific element. The concentration of the specific element in the catalyst layer (12) is higher in the first section (14) than in the second section (15), in terms of mass per unit volume. When the first section is divided in half along the thickness direction of the first catalyst layer (12), the ratio of a1 to a2, a1/a2, is 1.

Abstract: An exhaust gas purifying catalyst (10) according to the present invention is an exhaust gas purifying catalyst including the first catalyst layer (12). The first catalyst layer (12) includes the first section (14) and the second section (15) in the exhaust gas flow direction. The first section (14) is located on the upstream side in the exhaust gas flow direction relative to the second section (15). A catalyst layer (16) contains a catalytically active component including a specific element. The concentration of the specific element in the catalyst layer (12) is higher in the first section (14) than in the second section (15), in terms of mass per unit volume. When the first section is divided in half along the thickness direction of the first catalyst layer (12), the ratio of a1 to a2, a1/a2, is 1.