XNET Request/Grant/Deny Ownership Concept
This ownership mode applies to:
- Fire+Voice Panels: UL-864 9th ed.
- Fire-only Panels: UL-864 10th ed. and ULC-S527
The norms require a unique point of control (SPOC) for fire and voice systems.
In multi-stations systems, a software mechanism allows for assigning the ownership of fire panels to no more than one client station at a time (Request/Grant/Deny mechanism).
The owner station has full control over sending control commands such as acknowledge and reset to the panels it owns, and it is the only station enabled to issue commands to those panels. Operators of other stations can see what is happening in the panels, but if they try to command them, they will receive a Command denied error.
If you are operating a station that is the owner of a panel, what you can see and control is entirely determined by your user privileges. All other stations at your site are not permitted to send any commands to that panel.
From the owner station, you can contact authorized operators of other stations to transfer ownership to one of them. Similarly, while operating a non-owner station, you can request ownership to the owner station. To always ensure a safe assignment, a supervised protocol is applied during the transfers of ownership.
Requesting Ownership to the Owner Station
If you are operating a station that is not the owner of a selected panel, you can issue a Request for ownership. The request is forwarded to the owner station where a dialog box displays to enable the operator to accept or deny the request.
NOTE 1:
Whenever the system server starts, devices have no owner, and the same is true when a new device is added. In such a case, a request of ownership is automatically accepted. Whenever a management station stops or loses connection with the server, the related ownerships are reset to no owner.
NOTE 2:
A pre-configured timeout exists (120 seconds) to accept or deny a request. If the timeout expires, the ownership is automatically transferred to the requesting station. A longer timeout (5 minutes) is also applied to handle station failure conditions. All this allows for forcing a change of ownership if the owner station operator is not able to reply or if the owner station is somehow disconnected.
Transferring Ownership from the Owner Station
If you are operating an owner station, you can transfer ownership to another station. First, you select the station to which ownership will be transferred. A message is then forwarded to the selected station, where a dialog box displays to allow the operator to accept or deny the transfer.
NOTE:
A pre-configured timeout exists (120 seconds) to accept or refuse the ownership given from the owner. If the timeout expires, the transfer of ownership is refused. This prevents transferring the ownership to an operator who is not able to reply.
Request of Ownership Scenarios
The following describes system behavior in different scenarios for Requests of ownership based on operator acceptance or denial, and what happens if a request/transfer times out.
Let’s assume there are three stations:
- A station, owner of a set of roots of ownership
- B and C stations requesting ownership
The following scenarios may occur:
Request of Ownership Scenarios | |
Scenario | Result |
B requests ownership to A. A gives ownership within 120 seconds. | B becomes the owner. On A, the dialog box closes. |
B requests ownership to A. The timeout to accept/deny ownership expires. | B becomes the owner. On A, the dialog box remains open, and the operator can only click the Close button. |
B requests ownership to A. The timeout to accept/deny ownership expires. B requests a different ownership to A. | B becomes the owner of the first root of ownership. In the dialog box on A, the Accept Selection and Deny All buttons become available so that the operator can proceed with the request to transfer the second ownership. |
B requests ownership to A. A denies ownership. | A remains the owner. On A, the dialog box closes. |
B repeatedly requests ownership of the same root to A. A may accept/deny ownership or let the timeout expire. | One of the following occurs:
In all of the cases, the dialog box contains a single Requested Transfer item (despite repeated requests). |
B requests many roots of ownership in a single request to A. A may accept/deny ownership or let the timeout expire. | One of the following occurs:
In all of the cases, the dialog box contains all the Requested Transfer items. |
B requests many roots of ownership in a single request to A. C requests to A the same roots of ownership requested by B and possibly more. A may accept/deny ownership or let the timeout expire. | On A, two dialog boxes appear: one for B and the other for C. Assuming that the operator on A is working on the dialog box from B, s/he may accept, deny, or allow timeout of ownership requests. Based on actions on A, the C dialog box updates its Requested Transfer items accordingly, but remains open (the operator can click the Close button.) |
B requests many roots of ownership in a single request to A. C requests many roots of ownership to in a single request A (which are not the same requested by B). A may accept/deny ownership or let the timeout expire. | On A, two dialog boxes appear: one for B and the other for C. Assuming that the operator on A is working on the dialog box from B, s/he may accept, deny, or allow timeout of ownership requests. The C dialog box does not update its Requested Transfer items and remains open (the operator can click the Close button.) |
B requests ownership to A. A closes the client application. | Ownership is reset and B becomes the new owner immediately upon request. |
B requests ownership to A. For some reason, the dialog box on A does not display. This condition continues until the timeout expiration. | After a timeout of 5 minutes, ownership is automatically transferred to B. |
B requests ownership to A. For some reason, the dialog box on A does not display. This condition ends before the timeout expiration (for example, switchover completed).
| Ownership is automatically transferred to B as soon as the condition ends. |
The client application fails on A. | After a timeout of 5 minutes, ownership is automatically transferred to B. |
B requests ownership to A. A client application crashes before displaying the request. | Ownership is reset and B becomes the new owner immediately upon request. |
B requests ownership to A. A client application crashes after displaying the request. | Ownership is reset and B becomes the new owner upon the crash. |
B requests ownership to A. The dialog box displays on A. B client application crashes. A either accepts the transfer or lets the timeout expire. | The root of ownership no longer has an owner. |
B requests ownership to A. The dialog box displays on A. B client application crashes. A denies ownership. | A remains the owner. |
Transfer of Ownership Scenarios
The following describes system behavior in different scenarios for Transfers of ownership based on operator acceptance or denial, and what happens if a request/transfer times out.
Let’s assume there are three stations:
- A station, owner of a set of roots of ownership that it wants to transfer
- B and C stations, receiving ownership
The following scenarios may occur:
Transfer of Ownership Scenarios | |
Scenario | Result |
A transfers ownership to B. B accepts within 120 seconds. | B becomes the owner. The dialog box closes on B. |
A transfers ownership to B. B denies the transfer. | A remains the owner. The dialog box closes. |
A transfers ownership to B. The timeout to accept the request expires. | A remains the owner. The dialog box remains visible and the operator can only click the Close button. |
A transfers ownership of the same panel to B and C. | The dialog box displays both on B and C. The first station that accepts the transfer becomes the owner. The status of the request in the dialog box of the second client station becomes |
A transfers ownership to B. B requests ownership to A. | The dialog box displays both on A and B. If A accepts the request or B accepts the transfer, B becomes the owner. The status of the request in the dialog box of the station that did not accept the request or transfer becomes |
A transfers ownership to B. C requests ownership to A. | The dialog box displays both on A and B. If B accepts the transfer, it becomes the new owner. Otherwise, if A accepts the request, C becomes the new owner. The status of the request in the dialog box of the station that did not accept the request or transfer becomes |
A transfers ownership to B. A client application crashes or closes before B accepts, denies or the timeout expires. | The root of ownership no longer has an owner. The dialog box displays on B, and the status of the transfer becomes |
A transfers ownership to B. B crashes or closes the client application. | A remains the owner. |
A transfers ownership to B. B performs a switchover. | The dialog box closes on B, while A remains the owner. |
A Transfers ownership of a panel to B. A Transfers ownership of another panel to B. | The dialog box on B displays a list of all of the items for transfer. |
A transfers ownership of a panel to B. The timeout for B expires. A transfers ownership of another panel to B. | In the dialog box on B, the status of the first request becomes The second request is appended to the end of the dialog box list. |
A transfers ownership of a panel to B. Before the timeout for B expires, A transfers ownership of another panel to B. | In the dialog box on B, the status of the requests becomes |
Configuration Reference
In Desigo CC management stations, the ownership mode is controlled by a configuration option of the network.
In the configuration of the XNET fire control panel, in the Management Station Properties tab, make sure the check box Configured for Display only is selected.
This setting does not impact operations and does not prevent control of the fire network from Desigo CC when the Request/Grant/Deny feature is used.