| 摘要 |
PROBLEM TO BE SOLVED: To provide an authentication technique for the countermeasure of security used for a computer network by inserting a probe into at least one of plural files and identifying a position where the probing is executed in the computer network. SOLUTION: A communication traffic stream which enters and leaves a private network 130, etc., is consecutively monitored inside a fire wall 180. In this monitoring mode, a probe is inserted at random into a file arriving at the network 130. If this probing is executed at the client side, a signal is extracted to show a security warning. Thus, the wall 180 secures identification between the probe and a client and produces a security warning if a security warning showing the execution of a specific probe is received. |
