2 stage dialing

[Eugene Meyer]

Hi all.

I'm trying to configure 2 stage dialing but without data connectivity (IP connectivity), between Avaya, and Cisco. Here is the scenario:

We have an Avaya Call centre in country A, who needs to make calls to clients in country B, however there is only Cisco infrastructure in country B. What Im trying to configure is for the Call Centre agents to dial the Cisco gateway in Country B (via an access code or something like that), the gateway will then provide a dial tone to the agent who can then dial a client in country B from the gateway, and have a called number CLI of an extension residing on the Call Manager in country B.

Its worth mentioning that there is no IP connectivity between the two systems, so the call legs will all be established over the PSTN.

A diagram of the call flow will look like this.

Avaya agent --> GW --> PRI --> Country A SP --> Country B SP --> PRI --> Cisco GW (provides dial tone to agent, and makes call to client) --> Client in country B.

I had a look at the below Cisco document on how to configure two stage dialing with dial-peers, but see that the gateways still require data connectivity. So my question is, will this be possible with the set up Im facing, and if so, how do I configure this? I am also aware that this opens the network up for Toll Fraud, but this will be a short/dirty work around until we can get SIP trunks between the Cisco GW and SP.

http://www.cisco.com/c/en/us/support/docs/voice/voice-quality/22373-1stage2stage.html

This section in specific.

When the user picks up Phone 1, the dial tone is heard from the PBX. The user enters the digits and then hears another dial tone from the PBX/CO connected to Router B. There are two ways to achieve this:

1. Use direct-inward-dial on Router A.

   With direct-inward-dial configured, when the PBX/CO seizes the port on the router and sends a setup message that contains the DNIS digits. The router uses those digits to match an outbound VoIP dial-peer and sends the call to the remote router. Router B then seizes the line to its PBX/CO and does not forward it any digits. The remote PBX/CO then provides a dial tone to the user on Phone 1. It then appears as if the user is connected to that PBX/CO.

   This is the configuration for Router A:

   dial-peer voice 99 pots
   destination-pattern 1234
   direct-inward-dial 
   
   !--- This command is needed so that the router !--- routes the call based on the dialed digits.
   
   port 1/0:0
   prefix 1234
   !
   dial-peer voice 100 voip
   destination-pattern 5678
   session target ipv4:192.168.1.2

   This is the configuration for Router B:

   
   !--- This dial-peer matches the entire destination pattern, !--- strips it all off, and does not send any digits to the PBX/CO.
   
   dial-peer voice 201 pots
   destination-pattern 5678
   port 1/0:0
   

[Vivek Batra]

Happy to Help :)

- Vivek

[Ayodeji Okanlawon]

Vivek (+5)

It makes sense now. With MVA you tie the Avaya PSTN number to the internal DN and from there if all works you can dial out with the internal DN..

Good stuff!

[Ayodeji Okanlawon]

+5 to Vivek (great work as always)

Hi,

I need to point out to you that enabling two stage dialling has a big security risk. My customer has incurred huge phone bill for doing this. When rogues seize your line, they get a secondary dial-tone and can dial whatever pattern you have on that gateway. If this is a PSTN pattern you run a massive risk of incurring huge phone bill. This is one of the reasons why this feature was disabled in later IOS. It used to be enabled by default, but it is no longer and you have to manually enable it as Vivek has pointed out.

We have a golden rule. Never enable two stage dialling on any gateway! You risk been sacked if you do..Its that serious. I mean the customer incurred almost £80,000,00 of phone bills

[Carlo Poggiarelli]

Hi 

First of all +5 to Deji for his usual precious suggestion.

Than...

you could setup an ivr through bacd script with dial by extension option.

More info here

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucme/bacd/configuration/guide/cme40tcl/40bacd.html#wp1058592

HTH

Regards

Carlo

[Eugene Meyer]

Hi Ayeodeji

Thanks for the emphasis on the risks involved with 2 stage dialing. As mentioned in my post, I am aware of the toll fraud, but this client is adamant in getting this to work. Personally I would never suggest 2 stage dialing, however the client managed to come across a document on google and feels this is the way to go. I think I know now how a doctor feels when they see a patient who googled their symptoms :-/

I will definitely tell them about the £80,000,00 phone bill though.

[Ayodeji Okanlawon]

Eugene,

If the customer insists this is what they want, by all means please provide it to them however write a caveat sealed in gold of the risks of toll fraud. Then go ahead and open their PSTN line to the world!!! I am sure they would love it when the bills roll in..

Another thing is that there is no way that the CLI of the call will be from country B. The CLI will be of the original caller. If this is the motivation to do this, you need to let them know that. In fact it is possible that the CLI will be the main number on the trunk since most telcos will not allow you to pass a CLI that is not part of the DDI on a trunk..

May I ask why they cant just dial the clients in SB directly? May be this will help us get a bigger picture of what they are trying to do..

[Eugene Meyer]

So the reason for this is, a couple of months ago the client moved a business unit out of their office in country B to country A, however the business untit still has to make regular calls to customers in country B. The customers now see the CLI on their mobile phones as a international number and refuses to answer the call for some reason. The client has seen a 45% drop in their business since this move was done. They did the same thing in another country (country C) that runs on Avaya end-to-end and apperantly got 2 stage dialing to work, and made a white list using the phone number/s of the agents in country A, so that only these agents are able to dial the gateway and receive a secondary dial tone. As far as I know the white list uses IP addresses and not phone numbers, but I dont know about Avaya. As for the CLI, Im sure its possible to manipulate the CLI to a number on the Call Manager in country B...right?

Im also trying to see if there is a way that I can setup an IVR on CUC (the client has a CUC server in country B). Once the IVR answers the call it will ask for a PIN, and only after the correct PIN has been received will the secondary dial tone be given. Two things with this:

1. Im not sure if this is possible, and still looking into this option

2. The client is using a very old dialer system in country A, so even is this is possible, Im not sure how the dialer will respond to the request for a PIN once a call has been established to the CUC server.

[Ayodeji Okanlawon]

OK, this has confirmed my suspicion. The main issue here is the CLI displayed.

No unity cant provide a way for secondary dial-tone..So that's most likely out of it..

It all depends on the way the clients are dialled. If these are fixed clients, then you can configure CUC call handlers to send calls to these numbers and you can manipulate the CLI from cucm..If these are not fixed numbers, then its almost impossible to do with CUC, because you cant have wild card dialling in CUC

[Eugene Meyer]

Sadly these are not fixed numbers...otherwise I would have setup somesort of forwarding on the CM in country B.

[James Hawkins]

If a customer approached me with this problem my reaction would be to try to solve it using an IVR running on a UCCX server. This would allow PIN protection which would make toll fraud unlikely and not require any changes to the gateways.

If you have the free resources to host a virtual UCCX server you can install one and run for 30 days with a demo license which is found on the ISO image. You may even find that the customers CUCM system was shipped with a free 5 seat UCCX license which many 8.x systems did.