SilentKnight IP Alarm System Resiliency on Disaster Recovery and ISP changes - Manual (Page 5)

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Automatic Disaster Recovery
During disasters when the CMS staff must evacuate its facility or when the CMS IP Service goes down,
Internet Service Providers are usually unable to forward the IP address space on their Internet connection to
another location. In these circumstances, prior to falling back to a phone line communication, the IPDACT
automatically switches the IP to its secondary CMS.
In compliance with the NFPA-72
4 signaling standard for OT-PSDN 5 , the CMS notices the IP
communication failure of a subscriber account within 90 seconds. IPDACTs send polling request packets
every 90 seconds to the Main CMS and wait for the receiver response within that time interval (two-way
polling). If the IP polling fails, the system goes on backup, so that:
• The main receiver triggers a Communication Loss alarm on that account.
• The IPDACT switches to its backup receiver, keeping the complete Alarm Monitoring service.
The IPDACT will switch back to the main receiver on a normal operation as soon as the main IP
communication has been recovered.
Changing the CMS location or IP Service Provider
Instead of relying on the IP Alarm Monitoring Service on an external DNS service, IPDACTs make use of
IP tracking mechanisms offered by the ARLY communication protocol; so that they can be reprogrammed
with the new CMS IP addresses (backup and main) with very little effort from the CMS administrator and
no manual reprogramming in each Fire Panel location. Furthermore, during the CMS IP address space
modification, the Alarm Monitoring Service will not be disrupted.
During the Fire Panel installation, the VisorALARM downloads into the IPDACT the IP addresses of the
Main and Backup CMSs. The VisorALARM picks the IP addresses from the appropriate IPDACT
programming pattern in its Data Base. On the other hand, the VisorALARM keeps track of the IPDACTs
contact IP address since it caches it during the last polling interval.
When the IP address space of the CMS is modified, the IPDACTs are reprogrammed without disrupting the
Alarm Monitoring Service, following these steps:
1. The new IP address space is activated into the Main CMS. All the IPDACTs in the field switch to
the Backup CMS, as the IPDACTs haven’t been informed yet on how to reach the Main CMS in
the new address.
2. The new IP address from the Main CMS is edited into the appropriate programming pattern of the
Backup VisorALARM Data Base. With a one-click operation into the VisorALARM Manager
Application
6 , the IPDACTs are batched reprogrammed.
3. Once the batch reprogramming is completed, all the IPDACTs in the field will then reconnect to
the Main CMS at the new address.
4 NFPA: National Fire Protection Association
5 OT-PSDN: Other Transmission technologies – Packet Switched Data Networks. This standard details the
features required for an IP Communicator device so it does not need to fallback to a telephone alarm
transmission in case that the IP Communication goes down.
6 The VisorALARM Manager Application is the Windows based tool used for configuring and monitoring
the VisorALARM and the registered IPDACT accounts from the CMS dependencies.