Cisco Emergency Responder

I have been asked to research the feasibility of providing certain features of the CER within the FreePBX/Asterisk framework.

Is anyone else familiar with those features and how they might be accomplished using FreePBX?

I know, its a broad question.

The new E911 stuff that was just added to the latest version of FreePBX should be VERY close to what is offered in CER, without the $6000 price tag.

Apparently there’s one feature in particular that my management is asking about. The ability to track the last extension that dialed 911 and have emergency services inbound go to that extension even if it isn’t the normal target of the inbound route.

Submit a Feature Request. I’m sure that the notification component of the module can be extended to do that.

Which module would be the most appropriate? Inbound routes?

I’d have to wonder how FreePBX will manage the configuration of ERLs, considering that Emergency Responder uses SNMP and CDP against Cisco Catalyst switches in order to map Cisco SCCP phones to ERLs, and provide phone-roaming without updates.

That ERL is how callback happens - the outbound 911 call is mapped to an ERL that is a known Cisco switch(s) and all CDP discovered phones.

There are other ways to build ERLs though, including a manual import.

Callback is essentially an outbound translation pattern that provides ELIN to the PSAP, and a temporary inbound translation pattern is built to forward the call back to the last calling party.

It won’t. ERLs as implemented by Cisco are part of their expensive solution. Free telephony and SIP have no features that even pretend to look like that. For FreePBX, “ERL-lite” (which isn’t how FreePBX and Asterisk would handle this anyway) is going to have to be based on some kind of physical localizations either in the extension config in the server or something in the phone. The latter is a challenge since almost no hardware purveyors have given any thought to this, even in their new offerings. Older installations are going to be forced to manage this largely through the implementation of DIDs for locations at the minimum level of aggregation reasonable.

Now, part of the issue is that Cisco’s SCCP is a ‘server-centric’ protocol where the bulk of the processing, and therefore most of the control, is all server-side. This is why loading a Skinny phone with SIP firmware cripples the phone - the endpoints for an SCCP network interface are basically dumb terminals. So, since the processing of the call in a SIP network is largely at the endpoint, and the processing of a call in a CUCM network is at the server, a different approach is obviously going to be required.

Currently, the “extension” configuration for the SIP network includes a ‘e911’ Caller ID which is mapped to a reasonable location. With the limitations in place (and there are a couple of HUGE discussions that have been raging elsewhere in the forum for weeks), a different solution needs to be addressed here.

So, the local notification piece (let someone in reception know where the emergency is) should be the part when the “last call” component is fleshed out. There is a relatively wide constellation of use-cases for this, including single family dwellings, small businesses, factories, farms, stadiums, airports, and a dozen more, so a single solution that scales is something that really requires some thought. With the relatively short-notice for the requirements for this, a single FreePBX solution that meets all of the needs is going to be a challenge. I’m sure the new e911 module that Sangoma has put together is a start, but it’s probably going to be refined more and more over iterations of the different use cases.

Callback (currently) is handled as part of the extension configuration, so it is incumbent on the service providers (lower-case local IT guys) to be cognizant of the locations of the extensions, even though they technically follow the instrument (which is the SIP vs SCCP part) and move when the phone moves. Automating that is going to be a challenge, since most of the components in a SIP implementation are invisible. We don’t have CDP and DHCP through the network since these are things that SIP has never been concerned about.

In the past, people have added this functionality in either the ‘post-hook’ contexts or in the outbound route contexts. There have been lots of discussions on it over the past couple of years and Sangoma has added a new module for E911 notification and management. I haven’t even looked at it, so I’m working second-hand, but based on following the discussions, I’m going to guess that adding a “last 911 call” component to the rest of the notification code should be relatively simple.

I have opened an issue here:

[url fixed to be accessible to all - mod]

The more open equivalent to CDP is LLDP and specifically for location information it would be LLDP-MED. But for many this might mean upgrading switches. And there’s nothing I’m aware of currently that ties this information in to Asterisk/FreePBX automatically.

Try searching for 911 with the magnifying glass in the upper right corner.

That looks like a non-public URL but thank you for opening a ticket ! EDIT: Now it works thanks so much mod!! And I see the “Temporary inbound route for emergency services” issue you opened is addressed by some other solutions mentioned elsewhere in these forums, but labeled differently eg. “Dynamic call back numbers”.

This topic was automatically closed 31 days after the last reply. New replies are no longer allowed.