> emergency routing service for pbx


e999_logoAll 999 calls in the UK are routed to Emergency Call Centres that are operated either by BT or Cable & Wireless (C&W). The BT Emergency Call Centre handles 80% of UK 999 calls.

Both the BT and C&W Emergency Call Centres can process 999 calls that originate from anywhere in the UK. In other words they do not serve a specific location.

At each Emergency Call Centre there is a location database that is provisioned with the phone number of each phone line in the UK, together with the location information that is associated with that line.

When a 999 call is received at an Emergency Call Centre a database query is initiated so that the phone number associated with the call automatically triggers a screen pop-up that displays the location of the caller to the 999 operator.

This system works fine for 999 calls that originate on phone lines that serve domestic or small business premises, but if the phone lines are attached to an IP-PBX that serves multiple sites (sometime hundreds of sites) then there is a problem.

The problem is that the location information stored in the BT (or C&W) emergency location database is that of the PBX server on which the phone lines are terminated. The location information for the PBX server may be completely irrelevant since the 999 caller could be at a different site in a different part of the UK.

Barriers to a 999 solution for IP-PBXs

Assume that an organisation with a multi-line IP-PBX serving multiple sites has implemented an enhanced 999 solution that can attach calling line identity information (CLI) to a 999 call that references the precise location of the caller.

For example, if someone makes a 999 call from the London office the IP-PBX sets the CLI to 0300 999 0001, if the 999 call is made from the Manchester the CLI is set to 0300 999 0002 and if the 999 call is from the Glasgow office then the CLI is set to 0300 999 0003.

That organisation may reasonably think that all that is required to implement an enhanced 999 routing service is the deployment of an ISDN2 or ISDN30 connection that allows flexible presentation of emergency-only CLIs.

They would then need to request that BT or C&W provision ther 999 location databases with their emergency CLIs together with the specific addresses of the offices in London, Manchester and Glasgow.

Unfortunately, this apparently simple solution is not possible.

The main problem is that both the BT and C&W 999 routing services remove presentation CLIs from 999 calls and replace these with the network CLI of the ISDN line. As explained above, this would reference the location of the PBX server and is therefore likely to be completely different from the location of the 999 caller.

One of the reasons that this is done is that it is only the main CLI of the ISDN line and its location that is provisioned in the BT and C&W 999 location databases. In other words, ISDN presentation CLIs are not provisioned in the 999 location databases.

It would seem to be a straightforward matter to request that BT (or C&W) allow presentation CLIs to be used for 999 calls on a case-by-case basis and that these CLIs and their locations are provisioned in the 999 location database.

However, we have been advised by BT and C&W that for technical and other reasons this is not possible.

Solution: ConneXon E999 Emergency Routing Service

In order to implement a comprehensive enhanced 999 solution for workplace PBX phone system it is necessary to deploy an emergency routing service that bypasses existing ISDN lines and routes 999 call direct to the BT, or C&W, Emergency Call Centres.

To support their Emergency Gateway appliance ConneXon have developed a dedicated UK Emergency Routing Service and have chosen to route 999 calls from its customers directly to the BT Emergency Call Centre.

Although the ConneXon Emergency Routing Service is designed to add value to the ConneXon Emeregncy Gateway appliance it can also be used as a standalone service that can be provisioned on any IP-PBX.

The ConneXon Emeregncy Routing Service uses dedicated trunks that route calls directly to the BT 999 operator without any modification or removal of the CLI attached by the workplace PBX or the ConneXon Emergency Gateway appliance.

ConneXon would allocate CLIs for each Emergency Response Location deemed appropriate by the customer (eg room, floor, building and civic address) and would provision that CLI together with the location information in the BT 999 location database.

The customer would configure their PBX (or the Emergency Gateway) so that when a 999 call is made the appropriate CLI is attached to the call.

The ConneXon E999 Emergency Routing Service is a cost effective solution for organisations that wish to implement an enhanced 999 solution.

Deployment Scenarios

As mentioned above, the ConneXon E999 Emergency Routing Service supports the ConneXon E999 Emergency Gateway appliance, but it is also offered as a standalone service for organisations that have PBXs that are capable of applying a CLI mask according to the location of the caller.

Most IP-PBXs have this capability.

The ConneXon Emergency Gateway can identify precise 999 Emergency Response Locations that can be as granular as office, room or floor in addition to the civic address. It also offers may added value features such as Safety-Desk monitoring, text and email alerts and call recording.

The diagram at this link shows how the E999 Emergency Routing Service would operate in a PBX network that includes an E999 Emergency Gateway.

For those organisations that do not require the location granularity and value added features of the Emergency Gateway then it may be possible to use their PBX’s existing capabilities to attach location based CLIs for 999 calls. Most modern IP-PBXs have this capability as long as sites on the PBX network have clearly defined unique IP subnets.

If a location based CLI can be attached to a 999 call then a comprehensive enhanced 999 service can be offered by configuring the PBX to route all 999 calls to the SIP trunks provided by the ConneXon Emergency Routing Service.

The diagram at this link shows how the E999 Emergency Routing Service would operate in a PBX network that does not include an E999 Emergency Gateway.

Get in touch with us if you have a specific requirement or if you wish to discuss how your business could make better and more cost-effective use of its existing telecommunications and internet infrastructure and services.