Redirected Calls doesn't show External Phone Mask as CLID

[r2mehta1975]

All VoiP phones are set to use External Phone Mask 8666 XXXX. The router pattern for mobile calls also configured with following setting

Use Calling Party's External Phone Number Mask. So when outbound calls are made destination phone see the actual DN of the calling party eg if desk phone's DN is 2211, mobile phone will display caller id as 86662211.

I configured my desk phone (DN - 2211) set to forward calls to mobile phone. When some one calls my desk phone from PSTN/Mobile call gets redirected to my mobile but it appears it's coming from our main  front desk (86669999) instead of showing it's coming from 86662211 or the caller ID of the original caller. I don't where this transformation is happening but I have checked configuration of our outgoing h323 gateway and there is no translate calling option defined at all. CUCM Version in place is 6.1.3. Any Ideas ?

[Jonathan Schulenberg]

Are you using call forwarding or mobile connect to do this?

Also, debug the gateway to see what information is being transmitted to the provider. If you are using mobile connect, the external phone number mask from the directory number is not used. You would need to apply a transformation CSS to the remote destination profile. Mobile connect's default behavior is to pass the original calling party's information along; not the redirecting party.

[srsivara]

A lot of times, the provider does one of three things when they don't like a calling party number coming out of a VOIP network

- Replace the offending calling party number with 'Unknown'

- Replace the offending calling party number with the main billing number

- (Worst case) Reject the call, as the provider suspects it to be a fraudulent call from your VOIP network

If you have a PRI on the h.323 GW, you can run 'debug isdn q931', make the test call, and look at the calling party of the outgoing call to your cell. If the calling party shows up correctly on the debug, but the CLID on the cell is still the main billing number, you would need to call your Telco up and ask them to allow any calling party number from your VOIP network.

- Sriram

[r2mehta1975]

Hi Sriram,

Thanks for you reply. Let me bring this to your attention that we have mixed enviornemnt as we have some tradtional phones and lot of them converted to VoIP.We have two gateways in place. One is mgcp and has 2 E1 trunks to PABX. PABX has 2 E1 links used for incoming calls from our provider. The incoming E1 link is alsoused for outbound calls if call is made from tradtional phone. We have another gateway which H323 and has two E1 (PRI) primarily used for outbound calls.

My Understanding of Inbound Calls

Inbound call from PSTN destined for my desk phone (86664444) hits the PABX which looks at significant last 4 digits and check its configuration.If it's for VoIP phone it sends it call manager and call manager sends the signal to my phone. I can see the complete CLID of the PSTN phone trying to reach me unless it's coming from silent number then i don't see CLID

My Understanding of OutBound Calls

So for example  if STD / IDD/ Mobile call is made from my VoIP phone Call manager has route pattern to use (route list -->Router Group) H323 has preferred choice for outbound calls. I have checked the call history / active calls on the gateway and I can see my desk phone DN (86664444) becasue line settings are configured to use External Phone mask (8666XXXX) and I do see the called number. The route pattern for outbound mobile calls has following config

Calling Party Transformations

Use Calling Party's External Phone Number Mask
Calling Party Transform Mask
Prefix Digits (Outgoing Calls)
Calling Line ID Presentation	Default Allowed Restricted
Calling Name Presentation	Default Allowed Restricted

But when I configure my phone with CFwall to my mobile and when some one try to reach me from PSTN/ Mobile call comes through PABX, Call Manager redirects it to my mobile number . On my mobile I see that call is coming from our main reception number (not my desk extension, not the CLID of the phone which made the call). Don't know where this transformation is defined.

Also when I change my phones line settings and clear the External Phone Number Maskmask from 8666XXXX to blank and make outbound calls to PSTN/Mobile destination phone sees our main reception number not my desk number.

[srsivara]

From your description, it sounds to me that the provider could be overwriting the calling party number.  Run 'debug isdn q931', make the test call, and look at the calling party for the outgoing call to your cell. If the calling party shows up correctly on the debug, but the CLID on the cell is still the main billing number, you would need to call your Telco up and ask them to allow any calling party number from your VOIP network.

Example :

15:26:19.035 Q.931 0x01D3 SETUP           TX --> 192.168.9.1
SETUP pd = 8  callref = 0x01D3
Bearer Capability i = 0x8090A2
Transfer Capability: Speech, Transfer Mode: Circuit Mode , Transfer Rate: 64
Kbps, Layer 1 Protocol: G.711 u-Law Speech 
Channel ID i = 0xA98397
PRI Interface Exclusive channel ID Channel Number 23
Calling Party Number i = 0x0081, '9166148254'
Called Party Number i = 0x80, '9169201519'

- Sriram

[r2mehta1975]

Hi Sriram, Debug ISDN Q931shows that we allow the CLID to pass as it's .

1.So when my phone was NOT SET to use external mask then debug showed that calling number is "four digi extn 2211" but the destination phone dispayed our reception number.

2. When my phone was configured to forward all calls to my cell/ mobile and if some one from PSTN / Mobile number dialled to reach my phone 86662211 which in turn forward the call to my mobile - Gateway debug showed calling id of the originator  (0422245560) but my mobile displayed that call is coming from our main reception number

3. When my desk Phone was set to use External phone mask (8666XXXX) gateway debug showed that calling id as my  86662211 and when I dialled my mobile from my desk I saw the complete CLID

I will speak to the telco and ask them to look in to their configuration. In scenario 2 is there a way to change the originator caller id (0422245560) to my desk phone id (86662211) as it is set to forward call to my cell so that I know that call is coming from desk phone and which will also indicate that it's work related issue.

[srsivara · Accepted solution]

You can change the Calling party selection on the Gateway config page on CUCM, from 'Originator' to 'Last Redirect Number (External)'. Reset the gateway from CUCM Admin page after the change.

Let me know if that helps.

- Sriram

Please rate helpful posts.

[r2mehta1975]

Hi Sriram,

Thanks for all your help. I was able to prove it to Telco that the change is needed on their end with the help of the debug.

Regards,

Rakesh Mehta

[srsivara]

Hi Rakesh,

Glad to help !

- Sriram

[r2mehta1975]

Hi Jonathan, Thanks for your response. We are not using mobile connect at all. I am just configuring phone to forward all calls to my Mobile / Cell Number and expecting to see CLID as either my desk phone or the CLID of phone which is trying to reach my desk phone not the main reception number.