Adaptive supervisory rate for wireless intrusion detector

Abstract

A supervisory signal is received from the first wireless safety sensor at a first supervisory rate, the supervisory signal repeatedly validating that the first wireless safety sensor remains operably coupled to the safety system controller. A first safety sensor alert is received from the first wireless safety sensor, and in response, the first supervision rate is changed to a higher second supervision rate. A supervisory signal is received from the first wireless safety sensor at a second supervisory rate, the supervisory signal repeatedly validating that the first wireless safety sensor remains operably coupled to the safety system controller. When a second safety sensor alarm is received from the first wireless safety sensor within a predetermined period of time after the first safety sensor alarm, an alarm condition detection alarm is issued from the safety system controller.

Description

Technical Field

[0001] The present disclosure generally relates to security systems. More specifically, the present disclosure relates to security systems having wireless sensors. Background Art

[0002] Many security systems employ security sensors that are disposed about a facility protected by the security system. In some cases, individual security sensors may be susceptible to tampering in an attempt to break into the facility. If individual security sensors only check in with the security panel infrequently, it is possible for the security system to not report an alarm condition for a long period of time, particularly if the security system must verify an alarm condition detected by a security sensor before the security system reports the detected alarm condition. Verification of alarm conditions detected by security sensors may be desirable to reduce false alarms and thus increase the robustness of the security system. When so provided, if a security sensor is tampered with and goes offline before the detected alarm condition can be verified by the security system, the detected alarm condition may not be reported until, for example, the corresponding security sensor misses its next infrequent check-in time. It may be desirable to enable the security system to vary the rate at which security sensors check in to help avoid missing detected alarm conditions. Summary of the invention

[0003] The present disclosure relates generally to security systems, and more particularly to adaptive supervision rates for wireless security sensors within security systems. An example may be found in a method for operating a security system controller. The illustrative method includes receiving a supervision check-in signal from a first wireless security sensor at a first supervision rate, the supervision check-in signal repeatedly confirming to the security system controller when received that the first wireless security sensor remains operably coupled to the security system controller. A first security sensor alarm is received from the first wireless security sensor, the first security sensor alarm indicating an alarm condition detected by the first wireless security sensor. In response to receiving the first security sensor alarm from the first wireless security sensor, the first supervision rate is changed to a second supervision rate, wherein the second supervision rate is a higher rate (e.g., more frequent) than the first supervision rate. The method includes determining when a supervision signal is not received from the first wireless security sensor at the second supervision rate before receiving a second security alarm from the first wireless security sensor confirming the alarm condition of the first security sensor alarm, and in response, the security system controller issues a tamper alarm associated with the first wireless security sensor.

[0004] Another example may be found in a method for operating a security system including a plurality of security sensors. The exemplary method includes repeatedly verifying at a first supervision rate that each of the plurality of security sensors is in operation. When a first alarm is received from any of the plurality of security sensors, the first supervision rate of each of the plurality of security sensors is dynamically adjusted to a second supervision rate that is higher than the first supervision rate. The exemplary method includes repeatedly verifying at the second supervision rate that each of the plurality of security sensors is in operation.

[0005] Another example may be found in a method for operating a security system controller. The exemplary method includes receiving a supervisory signal from a first wireless security sensor at a supervisory rate assigned to the first wireless security sensor, the supervisory signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller. The exemplary method includes receiving a supervisory signal from a second wireless security sensor at a supervisory rate assigned to the second wireless security sensor, the supervisory signal, when received, repeatedly confirming to the security system controller that the second wireless security sensor remains operably coupled to the security system controller. In this example, the supervisory rate assigned to the first wireless security sensor is different from the supervisory rate assigned to the second wireless security sensor. The exemplary method includes: receiving a first security sensor alarm from the first wireless security sensor, the first security sensor alarm indicating an alarm condition detected by the first wireless security sensor; and receiving a second security sensor alarm from the first wireless security sensor within a predetermined time period of the first security sensor alarm, the second security sensor alarm confirming the alarm condition. The exemplary method includes issuing an alarm condition detection alarm from the security system controller after receiving the second security sensor alarm from the first wireless security sensor within the predetermined time period. In some cases, and in response to receiving the first security sensor alert from the first wireless security sensor, the supervision rate assigned to the first wireless security sensor may be changed to a higher supervision rate.

[0006] The above summary is provided to facilitate understanding of some innovative features unique to the present disclosure, but is not intended to be a complete description. A comprehensive understanding of the present disclosure can be obtained by viewing the entire specification, claims, drawings and abstract as a whole. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The present disclosure may be more fully understood by considering the following description of various examples in conjunction with the accompanying drawings, in which:

[0008] Figure 1 is a schematic block diagram illustrating an exemplary security system;

[0009] FIG. 2A to FIG. 2Care flow charts that collectively illustrate illustrative methods for operating a security system controller;

[0010] Figure 3 is a flow chart illustrating an exemplary method for operating a security system including a plurality of security sensors; and

[0011] Figure 4A and Figure 4B are flow charts that collectively illustrate illustrative methods for operating a security system controller.

[0012] Although the present disclosure is subject to various modifications and alternative forms, the details thereof have been shown by way of example in the accompanying drawings and will be described in detail. However, it should be understood that it is not intended to limit the present disclosure to the specific examples described. On the contrary, it is intended to cover all modifications, equivalents and alternatives that fall within the essence and scope of the present disclosure. DETAILED DESCRIPTION

[0013] The following description should be read with reference to the accompanying drawings, in which similar elements in different drawings are numbered in the same manner. The accompanying drawings are not necessarily drawn to scale, and they depict examples that are not intended to limit the scope of the present disclosure. Although examples of various elements are shown, those skilled in the art will recognize that many of the examples provided have suitable alternatives that can be utilized.

[0014] It is assumed herein that all numbers are modified by the term "about" unless the content clearly dictates otherwise. The recitation of numerical ranges by endpoints includes all numbers subsumed within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0015] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0016] It should be noted that references to "one embodiment", "some embodiments", "other embodiments", etc. in the specification indicate that the described embodiments may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, these phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it is contemplated that the feature, structure, or characteristic may be applied to other embodiments, whether or not explicitly described, unless otherwise explicitly stated to the contrary.

[0017] Figure 11 is a schematic block diagram illustrating an exemplary security system 10. The exemplary security system 10 may include a plurality of security sensors 12, labeled 12a, 12b through 12n, respectively. The security system 10 may include dozens, hundreds, or even thousands of security sensors 12. The security system 10 may include a variety of different types of security sensors 12, such as window open sensors, door open sensors, glass break detectors, motion detectors, fire sensors, smoke sensors, gas sensors, etc. In some cases, each of the security sensors 12 may communicate with a security panel 14. In some cases, at least some of the security sensors 12 may be wireless security sensors that communicate with the security panel 14 via any of a variety of different wireless communication protocols. The wireless security sensors may be battery powered.

[0018] In some cases, the security panel 14 may be part of the security system controller 16. In some cases, the security panel 14 may include the security system controller 16. In some cases, the security panel 14 and the security system controller 16 may be separate. In some cases, for example, at least some features of the security panel 14 and / or the security system controller 16 may be disposed in one or more edge controllers, while other features of the security panel 14 and / or the security system controller 16 may be disposed in one or more remote or cloud-based servers.

[0019] In the example shown, the security system controller 16 communicates with a central monitoring station 18. In some cases, the central monitoring station 18 may be configured to monitor alarms and other alerts from a plurality of different security systems 10 within a plurality of different facilities. For example, the central monitoring station 18 may be configured to display a dashboard that displays various alarms and other alerts so that a person can quickly see and ascertain what is happening in each facility. In some cases, the security system controller 16 may include the central monitoring station 18.

[0020] In some cases, if a first sensor alarm (e.g., motion, tampering, etc.) is received from any of the wireless security sensors, the security system controller may be configured to wait for the wireless security sensor to send a second sensor alarm that confirms the first sensor alarm before presenting an alarm notification to the operator of the CMS. This may help reduce the number of false alarms that must be handled by the operator of the CMS. However, if an intruder removes and / or destroys the wireless security sensor, such as after the first wireless security sensor issues the first sensor alarm, the second sensor alarm that confirms the first sensor alarm may never be received, and thus the alarm notification may not be provided to the operator of the CMS until a missing sensor alarm is generated at the next supervision time. When the supervision rate is, for example, once every 2 hours, then after the intruder removes and / or destroys the wireless security sensor, there will be up to 2 hours without a missing sensor alarm being generated for the first wireless sensor. In this case, the missing sensor alarm may serve as a confirmation of the first sensor alarm, and thus may cause the alarm notification to be presented to the operator of the CMS. To help avoid such delays, once the first sensor alarm is received from the first wireless security sensor, the supervision time of the first wireless security sensor is switched to a higher supervision rate (e.g., if the normal supervision rate is once every 2 hours, it is changed to once every 2 minutes once the first sensor alarm is received). After the supervision rate is changed to the higher supervision rate, a missed sensor alarm will be generated within a relatively short period of time (e.g., within 2 minutes), which causes a corresponding alarm notification to be presented to an operator of the CMS.

[0021] FIG. 2A to FIG. 2C 2 are flow charts that collectively illustrate an exemplary method 20 for operating a security system controller, such as security system controller 16. Method 20 includes receiving a supervisory signal from a first wireless security sensor, such as security sensor 12a, at a first supervisory rate that, when received, repeatedly verifies to the security system controller that the first wireless security sensor remains operably coupled to the security system controller, as indicated by block 22. The supervisory signal may be considered a heartbeat or check-in signal that identifies the first wireless security sensor and, in some cases, a current state of the first wireless security sensor. The current state may include, for example, a battery charge of a battery powering the first wireless security sensor and / or an operational state of the first wireless security sensor. These are merely examples.

[0022] The first supervision rate may be set to reduce power consumption of the battery of the first wireless security sensor by performing appropriately infrequent supervision check-in wireless transmissions from the first wireless sensor. In some cases, the first supervision rate may depend on the security level of the security system. For example, according to one standard (EN50131-1, Section 8.8.4.1, "Periodic communication"), for a Class 1 security panel, the maximum allowed interval between periodic communication signals or messages is 240 minutes, for a Class 2 security panel, the maximum allowed interval is 120 minutes, for a Class 3 security panel, the maximum allowed interval is 100 seconds, and for a Class 4 security panel, the maximum allowed interval is 10 seconds. A Class 1 intruder alarm system is only of interest to residential properties (there is no insurance requirement for the alarm system). A Class 2 intruder alarm system would be most residential properties and low-risk businesses (e.g., a florist). A Class 3 intruder alarm system would be suitable for high-risk residential properties and most commercial properties (e.g., a newsstand selling cigarettes). A Class 4 intruder alarm system would be suitable for extremely high-risk residential properties and higher-risk commercial properties (e.g., a gold store). These are just examples.

[0023] return Figure 2A , receiving a first security sensor alarm from the first wireless security sensor, the first security sensor alarm indicating an alarm condition detected by the first wireless security sensor, as indicated by block 24. In response to receiving the first security sensor alarm from the first wireless security sensor, changing the first supervision rate to a second supervision rate, wherein the second supervision rate is a higher rate (e.g., more frequent) than the first supervision rate, as indicated by block 26. The method 20 includes determining when a supervision signal is not received from the first wireless security sensor at the second supervision rate prior to receiving a second security alarm from the first wireless security sensor confirming the alarm condition of the first security sensor alarm, and in response, the security system controller issues a tamper alarm associated with the first wireless security sensor, as indicated by block 28.

[0024] When a supervisory signal is received from the first wireless security sensor at a second supervisory rate prior to receiving a second security alarm from the first wireless security sensor that confirms the alarm condition of the first security sensor alarm, the supervisory signal from the first wireless security sensor repeatedly confirms to the security system controller that the first wireless security sensor remains operably coupled to the security system controller, as indicated by block 29. In this example, a second security sensor alarm is received from the first wireless security sensor within a predetermined time period of the first security sensor alarm, the second security sensor alarm confirming the alarm condition of the first security sensor alarm, as indicated by block 30. For example, the predetermined time may be configurable. After receiving the second (i.e., confirming) security sensor alarm from the first wireless security sensor within the predetermined time period, an alarm condition detection alarm is issued from the security system controller, as indicated by block 32.

[0025] exist Figure 2B Continuing above, in some cases, the method 20 may also include receiving an acknowledgment of the alarm condition detection alarm, as indicated by block 34. In response to receiving the acknowledgment of the alarm condition detection alarm, changing the second supervision rate back to the first supervision rate of the first wireless security sensor, as indicated by block 36. Thereafter, receiving a supervision signal from the first wireless security sensor at the first supervision rate, the supervision signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller, as indicated by block 38. In some cases, the acknowledgment of the alarm condition detection alarm is received from a user via a user interface of a central monitoring station (CMS), such as central monitoring station 18. In some cases, the security system controller includes a security panel that is operably coupled between the first wireless security sensor and the CMS.

[0026] In some cases, a missing device alarm may be issued by the security system controller when a supervisory signal is not received from the first wireless security sensor at a first supervisory rate, the missing device alarm indicating that the first wireless security sensor no longer remains operably coupled to the security system controller. In some cases, a missing device alarm may be issued when a supervisory signal is not received from the first wireless security sensor at a second supervisory rate, the missing device alarm indicating that the first wireless security sensor no longer remains operably coupled to the security system controller. In some cases, the security panel issues a missing device alarm when a supervisory signal is not received from the first wireless security sensor at the second supervisory rate prior to receiving a second security alarm from the first wireless security sensor confirming an alarm condition of the first security sensor alarm, wherein the missing device alarm triggers a tamper alarm at the CMS, as indicated by block 39.

[0027] In some cases, method 20 may also include receiving a supervisory signal from a second wireless security sensor (such as security sensor 12b) at a first supervisory rate that, when received, repeatedly verifies to the security system controller that the second wireless security sensor remains operably coupled to the security system controller, as indicated by block 40. In response to receiving a first security sensor alarm from the first wireless security sensor, the first supervisory rate may be changed to a second supervisory rate for a second wireless security sensor (e.g., in addition to the first wireless security sensor), as indicated by block 42. Thereafter, a supervisory signal can be received from the second wireless security sensor at a second supervisory rate that, when received, repeatedly verifies to the security system controller that the second wireless security sensor remains operably coupled to the security system controller, as indicated by block 44.

[0028] exist Figure 2C Continuing above, the method 20 may also include receiving an acknowledgement of the alarm condition detection alert, as indicated at block 46. In response to receiving the acknowledgement of the alarm condition detection alert, the second supervision rate may be changed back to the first supervision rate for both the first wireless security sensor and the second wireless security sensor, as indicated at block 48. Thereafter, a supervision signal may be received from the first wireless security sensor at the first supervision rate, the supervision signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller, as indicated at block 50. Likewise, a supervision signal may be received from the second wireless security sensor at the second supervision rate, the supervision signal, when received, repeatedly confirming to the security system controller that the second wireless security sensor remains operably coupled to the security system controller, as indicated at block 52.

[0029] Figure 3 is a flow chart illustrating an exemplary method 54 for operating a security system, such as the security system 10, that includes a plurality of security sensors, such as the security sensor 12. The exemplary method 54 includes repeatedly verifying that each of the plurality of security sensors is in operation at a first supervision rate, as indicated by block 56. When a first alarm is received from any of the plurality of security sensors, the first supervision rate is dynamically adjusted to a second supervision rate that is higher (more frequent) than the first supervision rate for each of the plurality of security sensors, as indicated by block 58. The exemplary method 54 includes repeatedly verifying that each of the plurality of security sensors is in operation at a second supervision rate, as indicated by block 60.

[0030] In some cases, an alarm condition detection alarm is issued by the security system when a second alarm is received from the same security sensor of the plurality of security sensors from which the first alarm was received, as indicated by block 62. In some cases, the method 54 may also include receiving an acknowledgement of the alarm condition detection alarm, as indicated by block 64. In response to receiving the acknowledgement of the alarm condition detection alarm, the second supervision rate may be dynamically adjusted back to the first supervision rate for each of the plurality of security sensors, as indicated by block 66. The method 54 may include repeatedly verifying that each of the plurality of security sensors is in operation at the first supervision rate, as indicated by block 68. A missing device alarm may be issued when one or more of the plurality of security sensors is not verified to be in operation.

[0031] FIG. 4A to FIG. 4B 1 are flow charts that collectively illustrate an exemplary method 70 for operating a security system controller, such as security system controller 16. Exemplary method 70 includes receiving a supervisory signal from a first wireless security sensor, such as security sensor 12a, at a supervisory rate assigned to the first wireless security sensor, the supervisory signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller, as indicated by block 72. Receiving a supervisory signal from a second wireless security sensor at a supervisory rate assigned to the second wireless security sensor, the supervisory signal, when received, repeatedly confirming to the security system controller that the second wireless security sensor remains operably coupled to the security system controller, wherein the supervisory rate assigned to the first wireless security sensor is different from the supervisory rate assigned to the second wireless security sensor, as indicated by block 74.

[0032] In some cases, security sensors located within the perimeter of a facility may be more likely to be tampered with by an intruder attempting to enter the facility. Because perimeter sensors are more likely to be tampered with, these security sensors may have a more frequent supervision rate than those security sensors that are less likely to be tampered with during an attempted intrusion. Security sensors within the interior of a facility may have a less frequent supervision rate. As an example, security sensors within the perimeter of a facility may have a supervision rate of 5 minutes, while security sensors within the interior of a facility may have a supervision rate of 2 hours. Other supervision rates are also conceivable. It is conceivable that the supervision rate of each of the sensors may be user-configurable, and each sensor may be assigned a desired supervision rate depending on the type of sensor, the location of the sensor, and / or any other characteristics of the sensor. In some cases, the supervision rate of each sensor may be changed according to a user-programmable schedule. For example, one or more of the sensors may be scheduled to have a more frequent supervision rate at night or when the building is closed, and may be scheduled to have a less frequent supervision rate during the day or when the building is open for business. These are just examples.

[0033] by Figure 4A Continuing, a first security sensor alarm is received from the first wireless security sensor, the first security sensor alarm indicating an alarm condition detected by the first wireless security sensor, as indicated by block 76. A second security sensor alarm is received from the first wireless security sensor within a predetermined time period of the first security sensor alarm, the second security sensor alarm confirming the alarm condition, as indicated by block 78. After receiving the second (confirmed) security sensor alarm from the first wireless security sensor within the predetermined time period, an alarm condition detection alarm is issued from the security system controller, as indicated by block 80.

[0034] refer to Figure 4B , the exemplary method 70 may include, in response to receiving the first security sensor alert from the first wireless security sensor, changing the supervision rate assigned to the first wireless security sensor to a higher supervision rate (more frequent) assigned to the first wireless security sensor, as indicated at block 82. The method 70 may include, in response to receiving the first security sensor alert from the first wireless security sensor, changing the supervision rate assigned to the second wireless security sensor to a higher supervision rate assigned to the second wireless security sensor, as indicated at block 84.

[0035] In some cases, the method 70 may include receiving an acknowledgement of the alarm condition detection alert, as indicated at block 86. In response to receiving the acknowledgement of the alarm condition detection alert, the supervision rate assigned to the first wireless security sensor may be changed from the higher supervision rate assigned to the first wireless security sensor back to the original supervision rate assigned to the first wireless security sensor, as indicated at block 88. In some cases, in response to receiving the acknowledgement of the alarm condition detection alert, the supervision rate assigned to the second wireless security sensor may be changed from the higher supervision rate assigned to the second wireless security sensor back to the original supervision rate assigned to the second wireless security sensor.

[0036] Although several exemplary embodiments of the present disclosure have been described in this manner, it will be readily understood by those skilled in the art that other embodiments may be made and used within the scope of the claims appended hereto. However, it should be understood that the present disclosure is in many respects merely illustrative. Details (especially details related to shape, size, arrangement of parts, and exclusion and order of steps) may be changed without exceeding the scope of the present disclosure. Of course, the scope of the present disclosure is defined in the language of the appended claims.

Claims

1. A method for operating a safety system controller, the method comprising: receiving a supervisory signal from a first wireless security sensor at a first supervisory rate, the supervisory signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller; receiving a first security sensor alarm from the first wireless security sensor, the first security sensor alarm indicating an alarm condition detected by the first wireless security sensor; in response to receiving the first security sensor alert from the first wireless security sensor, changing the first surveillance rate to a second surveillance rate, wherein the second surveillance rate is a higher rate than the first surveillance rate; as well as Prior to receiving a second security alarm from the first wireless security sensor confirming the alarm condition of the first security sensor alarm, determining when the supervisory signal is not received from the first wireless security sensor at the second supervisory rate, and in response, the security system controller issues a tamper alarm associated with the first wireless security sensor.

2. The method according to claim 1, comprising: when the supervisory signal is received from the first wireless security sensor at the second supervisory rate prior to receiving the second security alarm from the first wireless security sensor confirming the alarm condition of the first security sensor alarm, the supervisory signal from the first wireless security sensor repeatedly confirms to the security system controller that the first wireless security sensor remains operably coupled to the security system controller; receiving, from the first wireless security sensor, a second security sensor alarm within a predetermined time period of the first security sensor alarm, the second security sensor alarm confirming the alarm condition of the first security sensor alarm; as well as The security system controller issues an alarm condition detection alert after receiving the second security sensor alarm from the first wireless security sensor within the predetermined time period.

3. The method according to claim 2, comprising: receiving an acknowledgement of said alarm condition detection alarm; in response to receiving said acknowledgement of said alarm condition detection alert, changing said second supervision rate back to said first supervision rate of said first wireless security sensor; as well as A supervisory signal is received from the first wireless security sensor at the first supervisory rate, the supervisory signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller. 4 . The method of claim 3 , wherein the confirmation of the alarm condition detection alert is received from a user via a user interface of a central monitoring station (CMS). 5 . The method of claim 4 , wherein the security system controller comprises a security panel operably coupled between the first wireless security sensor and the CMS.

6. The method of claim 5, wherein the security panel issues a missing device alarm when the supervisory signal is not received from the first wireless security sensor at the second supervisory rate prior to receiving the second security alarm from the first wireless security sensor confirming the alarm condition of the first security sensor alarm, wherein the missing device alarm triggers the tamper alarm at the CMS.

7. The method according to claim 2, comprising: receiving a supervisory signal from a second wireless security sensor at the first supervisory rate, the supervisory signal, when received, repeatedly confirming to the security system controller that the second wireless security sensor remains operably coupled to the security system controller; in response to receiving the first security sensor alert from the first wireless security sensor, changing the first surveillance rate to the second surveillance rate of the second wireless security sensor; and A supervisory signal is received from the second wireless security sensor at the second supervisory rate, the supervisory signal, when received, repeatedly confirming to the security system controller that the second wireless security sensor remains operably coupled to the security system controller.

8. The method according to claim 7, comprising: receiving an acknowledgement of said alarm condition detection alarm; in response to receiving said acknowledgement of said alarm condition detection alert, changing said second supervision rate back to said first supervision rate for both said first wireless security sensor and said second wireless security sensor; receiving a supervisory signal from the first wireless security sensor at the first supervisory rate, the supervisory signal, when received, repeatedly confirming to the security system controller that the first wireless security sensor remains operably coupled to the security system controller; as well as A supervisory signal is received from the second wireless security sensor at the first supervisory rate, the supervisory signal, when received, repeatedly confirming to the security system controller that the second wireless security sensor remains operably coupled to the security system controller.

9. The method of claim 1, wherein the first wireless security sensor comprises one or more of a motion sensor, a glass break sensor, a fire sensor, a smoke sensor, and a gas sensor.

10. The method of claim 1, wherein the security system controller comprises one of: Security panels; Central Monitoring Station; and A security panel is operably coupled to the central monitoring station.

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