Method and system for detecting alarm system tampering

摘要

An alarm system monitors a home, business, or other property for fire, burglary, break-in, or other event that may warrant raising an alarm. The alarm system is configured to detect tampering, whereby someone intentionally impedes the ability of the system to raise an alarm or otherwise interferes the system's operation. An alarm panel of the alarm system communicates with a server. At certain times, the alarm system transmits a series of packets to the server using a unidirectional protocol. Upon receipt of one of the packets, the server alternates between monitoring for an incoming packet and ignoring any incoming packets. Detection of an incoming packet during a monitoring time period causes the server to transition to ignoring packets for a sleep period of time. Completion of the sleep period of time causes the server to return to monitoring for the monitoring period of time.

主权项

1. A server comprising:
a first communication interface that is configured to receive communications transmitted from an alarm panel, wherein the alarm panel is configured to transmit an arming notification, a disarm notification, an intrusion alarm, and packets transmitted periodically in a unidirectional communication protocol when a sensor connected to the alarm panel is triggered, wherein the alarm panel is further operable to stop transmitting packets in the unidirectional communication protocol when an alarm delay of the alarm panel expires or when the alarm panel is disarmed; a second communication interface that is configured for bidirectional communication with a central monitoring station; a processor that comprises:
a first connection to the first communication interface;a second connection to the second communication interface;memory; and processor executable instructions stored in the memory to perform the steps of:
monitoring for the arming notification transmitted from the alarm panel;monitoring for the disarm notification transmitted from the alarm panel;monitoring for the intrusion alarm transmitted from the alarm panel;responsive to receipt of the intrusion alarm, notifying the central monitoring station of the intrusion alarm;alternating between:
for a first period of time, monitoring the first communication interface for a packet of the packets transmitted periodically in the unidirectional communication protocol from the alarm panel when the sensor connected to the alarm panel is triggered; andfor a second period of time, ignoring the packets transmitted periodically in the unidirectional communication protocol from the alarm panel when the sensor connected to the alarm panel is triggered,wherein detection of the monitored-for packet of the packets transmitted periodically in the unidirectional communication protocol from the alarm panel during the first period of time suspends the packet monitoring of the first period of time and initiates the second period of time, andwherein completion of the second period of time without detecting the monitored-for disarm notification and without detecting the monitored-for intrusion alarm initiates a subsequent execution of the first period of time; andresponsive to a completion of the subsequent execution of the first period of time during which the monitored-for packet has not been detected, the monitored-for disarm notification has not been received, and the monitored-for intrusion alarm has not been received, notifying the central monitoring station of an occurrence of a tampering event.