Who would have thought that the BS8521:2009 protocol should see an upswing at the time when the analogue networks are in the process of being phased out? Continue reading to understand how digital care devices can work with Alarm Receiving Centres in Europe supporting the BS8521 protocol.

Dusting off the BS8521 Protocol

The British Standard BS8521:2009 was prepared as a request from purchasers and users of social care alarm systems to establish a common signalling protocol and compatibility between device manufacturers and Alarm Receiving Centres. The idea was good, but in practice most devices continued to communicate with the ARCs through already established and in many cases proprietary care protocols.

Today, many Alarm Receiving Centres have implemented support for BS8521:2009, although not widely known. In the years to come the new IP based protocols SCAIP and NOW-IP* will be the de facto standards.

What if your Alarm Receiving Centre only supports the analogue version of BS8521, but you want to connect digital devices? Would it be possible to establish a communication bridge between new digital units and legacy ARCs running BS8521:2009?

Seamless bridging between old and new worlds

Our serverless and cloud based Alarmbridge can handle both analogue and IP based protocols and make seamless bridging between the analogue and digital worlds. For example, a SCAIP alarm can easily be bridged into an analogue BS8521 alarm but bridging the alarm communication is not all! In like manner VoIP calls can be bridged with analogue voice calls to establish direct connection between users and alarm centre agents, and vice versa.

Below is a practical example of how digital devices, with or without SCAIP, can be incorporated into modern solutions and communicate with existing Alarm Receiving Centres that support legacy protocols.

Connect digital devices to analogue ARC – step 1

An alarm is sent from a digital device

An alarm is sent to Alarmbridge, as a SCAIP message, or as an event through an API integration
Connect digital devices to analogue ARC – step 2

Alarmbridge sends the alarm to the ARC

Alarmbridge establish a connection to the ARC and communicate via the analogue protocol BS8521:2009.
Connect digital devices to analogue ARC – step 2

Alarmbridge notifies the device

At the same time, Alarmbridge communicates with the SCAIP device, or the platform integrated through API, to inform that the alarm has been delivered to the ARC.
Connect digital devices to analogue ARC – step 3

Voice communication is setup with device

If the ARC would like to establish a voice call through the already established connection from the incoming alarm, Alarmbridge can send a message to the device asking it to setup a phone call (GSM or VoIP) into Alarmbridge.

Calling legs from device & ARC are joined

When the call is received, Alarmbridge can join the two calling legs into one session and the parties can talk to each other.

Future compatibility between care devices and Alarm Receiving Centres will be based on the new IP standards SCAIP and NOW-IP. However, one of the biggest challenges with the digital shift is to find ways for old analogue solutions to co-exist with modern solutions during a transition phase. Alarmbridge will allow for a smoother migration at your own pace and future-proof your service towards a fully digital world.

* The British Standard NOW-IP (also known as BS8521:2020) was released in 2020, enabling an IP signaling protocol specifically for group livings. Similar to SCAIP and CENELEC TS 50134-9, the protocol transmits alarm events using the SIP MESSAGE method and is able to set up voice communication using SIP VoIP.

Do you need to bridge from digital to BS8521?

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