Provided is an information processing device in which a sub response part (SRP) provides a response on behalf of a main response part (MRP) for enabling a provision of an easy coordination between the MRP and the SRP in protocol process. A network connection part is for receiving a packet from an external network. A distribution function part of a filter part distributes the packet to either one the MRP and the SRP based on a packet distribution condition. A duplicate function part of the filter part, if no response data is stored in the SRP, duplicates the packet received and gives the packets to the MRP and the SRP. Thereby, the SRP receives response data from the MRP to store the same in a response data storage area and provides a response on behalf of the MRP using the stored response data.