COMMUNICATION SYSTEM, METHOD, AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To enable reduction in a processing load while appropriately protecting security.SOLUTION: A communication packet on a communication protocol includes in its header information: an encryption flag indicating whether the communication packet is encrypted or not; upper-level layer information indicating information on an upper-level layer to be used for communication of the communication packet; and a stream ID for identifying communication performed on the communication protocol. On the basis of a stream ID associated with a host name of a server device 20, a client device 10 sets an ID number not overlapping with the stream ID in use corresponding to the host name as a stream ID when staring communication. Each of the devices 10, 20 selects whether the communication packet is to be encrypted or not, sets the encryption flag on the basis of the selection result, and sets upper-layer information. Each of the devices 10, 20 transmits and receives a plurality of communication packets with different stream IDs set thereto, on a single lower-level layer connection.SELECTED DRAWING: Figure 4