| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a simple security system capable of detecting whether a suspicious person has invaded a premise or not and identifying an invasion site.SOLUTION: In a PBX 100, an operation mode setting unit (MODE) 101 sets one of two operation modes, i.e. a telephone mode for a normal telephone function and a security mode for monitoring whether a suspicious person has invaded or not for each one of areas that are a first security object area 11 and a second security object area 12 obtained by division in a site. When the security mode is set in the first security object area 11, for example, peripheral sound is collected by the microphones of respective telephone sets 120-122 within the area 11. When abnormal sound indicating the invasion of a suspicious person is detected by one of the telephone sets, for example, a telephone set 120 and a connection request is received from the telephone set 120, a state is set to a one-way sound pass connection state for transferring the sound from the telephone set 120 to a telephone set 110 of a security office 10 via a conference trunk 102. Besides, information for identifying the telephone set 120 by which abnormal sound has been detected is held in a storage area 103.</p> |
