Understanding Signalling Types For Monitored Alarms: What They Mean?
Single Path vs Dual Path Alarm Monitoring: What’s the Difference?
When choosing an alarm monitoring solution, understanding the difference between Single Path (SP) and Dual Path (DP) signalling is important. The signalling path determines how alarm events are transmitted from your premises to the Alarm Receiving Centre (ARC) and can have a significant impact on resilience, reliability and compliance requirements.
What Is Single Path (SP) Alarm Signalling?
Single Path (SP) signalling uses a single communication route to transmit alarm events.
This route may use:
- IP connectivity via Ethernet
- Radio communications using 4G or 5G mobile networks
Because there is only one communication path available, a failure affecting that route may interrupt signalling until the fault is resolved.
What Is Dual Path (DP) Alarm Signalling?
Dual Path (DP) signalling uses two independent communication routes, providing greater resilience and reducing the risk of complete communication loss.
Typical dual-path configurations include:
- IP + Radio (Ethernet and 4G/5G)
- Radio + Radio (multiple SIMs operating on independent mobile networks)
If one communication route fails, the system can continue to signal using the secondary path.
Why Dual Path Signalling Is Commonly Recommended
The main advantage of dual-path signalling is redundancy.
If one signalling path becomes unavailable because of a broadband failure, network outage or local infrastructure issue, the secondary path remains available to maintain communication with the Alarm Receiving Centre.
This additional resilience is often required by insurers and may be considered for higher-risk premises.
Why Hard-Wired Connections Are Often Preferred
Whilst Wi-Fi connectivity may be suitable in some circumstances, hard-wired Ethernet connections are generally preferred for alarm signalling because they typically offer greater stability and reduced reliance on wireless infrastructure.
Dedicated wired connections can also help minimise potential issues caused by interference, wireless coverage limitations or local network changes.
Common Signalling Issues Identified During System Reviews
When reviewing monitored alarm systems, common issues include:
- Legacy communicators still reliant on ageing technologies
- Single-path signalling where dual-path resilience may be more appropriate
- Poorly documented ARC arrangements
- Inadequate signalling grades for current insurer requirements
- Network infrastructure changes that affect signalling performance
Many organisations are surprised to discover that their signalling arrangements no longer match their insurer’s expectations or the current risk profile of the premises.
Polling Times and Catastrophic Failure Reporting
Alarm signalling devices are regularly polled to confirm that communication remains available.
If the communicator fails to respond within the defined period, the Alarm Receiving Centre receives a communication loss notification.
| Single Path | Dual Path | Catastrophic Failure Reporting |
|---|---|---|
| SP2 | DP1 | 25 Hours |
| SP3 | DP2 | 31 Minutes |
| – | DP2+ | 11 Minutes |
| – | DP3 | 4 Minutes |
| – | DP4 | 3 Minutes |
Signalling standards and catastrophic failure reporting times have evolved significantly in recent years, with newer SP and DP classifications replacing older grading terminology. 【1-331687】【2-0b7cc1】
What Is DP2+?
DP2+ is commonly selected because it provides a good balance between resilience, reporting speed and ongoing running costs.
For many commercial properties, schools and public-sector buildings, DP2+ offers an appropriate level of protection whilst maintaining cost-effectiveness.
When Might a Higher Signalling Grade Be Required?
Insurers may specify minimum signalling grades based on risk assessments, asset values and occupancy characteristics.
Higher signalling grades such as DP3 or DP4 may be considered where faster communication failure reporting is required or where risk profiles justify enhanced resilience. Certain fire alarm applications may also require higher levels of signalling performance. 【1-331687】【3-4d8472】
Frequently Asked Questions
What is the difference between Single Path and Dual Path signalling?
Single Path uses one communication route, whilst Dual Path uses two independent routes to provide greater resilience.
What happens if a communication path fails?
With Dual Path signalling, communication can continue via the secondary path. Single Path systems rely on their sole signalling route remaining available.
Do insurers require Dual Path signalling?
Many insurers specify signalling grades based on risk assessments and property characteristics. Requirements vary depending on the risk profile of the premises.
What is catastrophic failure reporting?
Catastrophic failure reporting refers to the time taken for a complete communication failure to be identified and reported to the Alarm Receiving Centre.
Final Thoughts
Selecting the correct alarm signalling solution is just as important as choosing the alarm system itself. The appropriate signalling grade should consider the level of risk, insurer requirements, operational needs and the importance of maintaining continuous communication with the Alarm Receiving Centre.
If you’re unsure whether your current alarm monitoring solution is appropriate, i Security can review your signalling arrangements and provide practical advice on Single Path, Dual Path and insurer-compliant alarm monitoring solutions.