Vehicular communication control apparatus

A vehicular communication control apparatus that is interposed, for relaying messages, between an Internet-protocol-based network and an in-vehicle local area network in order to enable transmission and reception of the messages between external tools connected to the Internet-protocol-based network and an in-vehicle electronic control unit connected to the in-vehicle local area network, the vehicular communication control apparatus comprising:

• a forwarding section for, upon receipt of the messages from the external tools, forwarding the messages to the in-vehicle electronic control unit that is to receive the messages, wherein the external tools include a first external tool and a second external tool provided separately from each other;
• a storing section for storing a class of a message from the first external tool when the forwarding section forwards the message from the first external tool to the in-vehicle electronic control unit, wherein the storing section stores the class of the message from the first external tool until communication, which is between the first external tool and the in-vehicle electronic control unit and is attributed to the message from the first external tool, is ended;
• and
• an interference determination section for, when the vehicular communication control apparatus receives a message addressed to the in-vehicle electronic control unit from the second external tool while the in-vehicle electronic control unit is communicating with the first external tool,
• making a determination as to whether or not an interference of operations of the in-vehicle electronic control unit is caused by the message from the second external tool and the message whose class is stored by the storing section, based on a class of the message from the second external tool and the class of the message stored by the storing section,
• wherein:
• when the interference determination section determines that the interference of operations of the in-vehicle electronic control unit is not caused, the forwarding section forwards the message from the second external tool to the in-vehicle electronic control unit.