112 / 911 emergency question

[corre44]

Hi There,

Most of our customers are call centers and they ask us to block all outbound calls from extensions which don't have agents logged in.
But that conflicts with local law which clearly states that all phones need to be able to dial 911 or 112 calls. And the law even states that the person dialing the emergency number doesn't even have to dial an ARS access digit/string.
Simply dialing 911 or 112 should work.
So, all our customer's phones have COR 0 (FRL 0).
All our customer's PBX systems have a Route Pattern 1 with several trunk groups assigned to it and FRL 0.
All our customer's ARS is configured with "string-112, min-3, max-3, route-1, type-pubu".
This means that any station in the PBX can dial 0 (ARS access digit) and 112 and the call is placed.
The question here is: how can I make it work without them having to dial the 0 for the ARS? I saw something in a blog mentioning "ars digit-conversion" but I don't know how that works and when I try to set it up I get a "denial event".
Thanks in advance.

Cheers

[alb293]

There are a few ways to do it. You can do it in the ars digit conversion table, but it would be better to add the 0 in the routing patterns. For instance, I have two routing patterns for 911: 911 and 11. That way, if a user fails to dial the extra 9 to dial externally, and just dials 911 (system sees this as dialing "11"), it will still go through. The 9 is inserted in the routing pattern. This is required by law in the US. Google "Kari's Law" for more info.

[corre44]

Okay, I think I'm missing something here.
In the US, the emergency is 911 and it is usual to find the ARS access digit to be 9.
Which means that people will either dial 9 for accessing the ARS and then 911 (full string is 9911) or people will only dial 911.
In the latter, the system is "dumb" and thinks the 9 is still the ARS access digit.
That means in the US, tech guys need to cover for both possibilities.

In Europe OTOH, the usual digit for accessing the ARS is 0 (except UK) and the emergency number is 112.
So, we have to cover both scenarios. Either 0112 or just 112.
In this case, how would I use the "ars digit-conversion" in order to allow the stations to just dial 112 and place the call through a landline?
The config options are, Matching Pattern, Min, Max, Del, Replacement String, Net, Conv, ANI, Req.
I was wondering it would look like:
pattern-112, min-3, max-3, del-0, string-0112, net-ars, conv-n,req-n
But this fails miserably on me with a denial event, whereas dialing 0112 from the phone works just great.
Thanks in advance.
Cheers

[alb293]

It's the same problem in both countries. You don't want the user to have to dial an access number for emergency calls. The way to do this in the route pattern (which is what worked for me, I didn't even attempt the ars digit conversion) is as follows:
You will need a routing pattern for each location, using the local trunks there. Set up your routing pattern for the 211 condition. Enter the location Trunk Group, FRL 0, NPA for that location, nothing in the next 4 fields is necessary, then in Inserted Digits put "0". Save this routing pattern.
Then, in the ARS analysis table for each location, enter dialed string 211, Total Min 3, Total Max 3, the routing pattern that you created for the 211 condition in that location, then Call Type "emer". Save.

[alb293]

The ARS should work as well, but you will still need to edit the table for each location:
"change ars digit-conversion location X"
I prefer the route patterns, as the ARS digit conversion is kind of hidden when tracing calls. It aids in troubleshooting.

[corre44]

[Note] I was writing this while you posted the previous 2 posts...

Okay, I've been reading the manual and it seems that, if I use the ars digit-conversion, apparently I don't need to use 0112 as the replacement string. I just need to use 112 in the replacement string and set the net as ars.
I've tried that and it didn't work. Denial event.
But suddenly, it seems to me that the ars digit-conversion is not what I am looking for. I am looking for a way to dial 112 and make the system understand that this is not an internal call and that it needs to check the ARS tables in order to choose a route pattern to place the call.
In the UK/US this works great because you guys use the 9 for outbound calls. So, the person dials 911 and without knowing is already dialing the ARS access digit. And then you use the ars digit-conversion to convert 11 into 911 again.
This is not what happens in EU world. We dial 0 for outbound calls and our emergency number is 112.
This would work only if our ARS access digit was 1. The system would interpret 1 as the ARS access digit and then we would use the ars digit-conversion to convert 12 into 112. Easypeasy.
Now, how do we make this work for 112 with 0 as the ARS access digit?
Thanks in advance.
Cheers

[corre44]

Set up your routing pattern for the 112 condition.
Enter the location Trunk Group, FRL 0, NPA for that location, nothing in the next 4 fields is necessary, then in Inserted Digits put "0". Save this routing pattern.
Then, in the ARS analysis table for each location, enter dialed string 112, Total Min 3, Total Max 3, the routing pattern that you created for the 211 condition in that location, then Call Type "emer". Save.

This isn't working for me. And it's not making sense either.
First thing is, how does the dialed string even gets to the ARS analysis table if the station is not dialing 0 in front of the 112.
Now, let's say that it gets there. I dial 112 and the system uses the ARS tables, finds a match which states that the call is 'emer' type and that it needs to be routed throug the routing pattern 1.
Routing pattern 1 is setup with a single trunk group 1, with FRL 0 and it has a 0 in the inserted digits.
To me, that means that I dialed 112, went through the ARS tables, found the routing pattern 1 table and now the call is being routed to trunk group 1 with '0 112'.
In this what it does? It adds a 0 and tries to put the call through trunk 1? If so, this is definitely not what I am looking for.
But please correct me if I am wrong (I must be): does the call even get to look at the ARS tables? Because I'm not dialing any 0, just 112. If so, how can the call be looking at the ARS tables in the first place?
Thanks in advance.
Cheers

[alb293]

It won't hit ARS at all, you're right. Can't use ARS digit conversion or Routing Tables, since you have to hit the ARS in the first place to get routed. Try the dialplan analysis table. You'll need to set 112 as a udp type call, length 3. You don't have any extensions that start 112, do you?


So, change dialplan analysis, add 112. Then change uniform-dialplan, add 112 len 4, del 0, insert "0", net ars, conv n
It will then hit the ars table as 0112.


Try that. I am an idiot.

[corre44]

Hi alb293,

Thanks for your help.
Still no joy. Denial station xxxx.
I've removed any previous configuration that we had been trying out.
Then I changed the 'dialplan analysis' and added string-112, length-3, type-udp.
After that I changed the 'uniform-dialplan' and added pattern-112, len-4 (tried with 3 too), del-0, insert-0, net-ars. Still doesn't work.
I even tried to delete all 3 digits and insert 0112 but I still get a denial station... :-(
Any ideas?
Thanks in advance.

Cheers

[alb293]

What do you get on the trace for that call?