It is actually fairly easy. You just have to decide at which level you want to transform the calling party.

There are a number of ways to skin this cat depending on how you setup your phones....

METHOD 1 Probably Best

First go to CM > Device > Phone > Find > And pick a local ip phone.

Select Each Line Appearance and check the External Phone Number Mask field. IT SHOULD look something like 416438XXXX. If so, GREAT continue on Method 1. If not, you either want to add that to each line appearance of every phone or move to Method 2.

Now go CM > Route Plan > Route List > Choose PSTN Gateway RL > Route Details for PSTN Gateway RL > Change the use calling Party's External Phone Number Mask to ON

Note: That this will override the Route Pattern Configuration as stated on the page. Which means that if you want to be more granular and apply the External Phone Number Mask based on the Route Pattern matched instead of the Route List / Gateway used then ...

Try going to the CM > Route Plan > Route Pattern > Find and select the appropriate pattern (for example 9.@ for external calls) > and then check the check box for Use Calling Party's External Phone Number Mask

Again, there are SO MANY ways to do this you just have to decide WHO needs to see WHAT caller-id. Personally we want outside phones to see AND inside callers to see .

NOW, if you don't have each phone's External Phone Number Mask configured on each line appearance then there is a way to cheat.

METHOD 2 CHEATER!

Now go CM > Route Plan > Route List > Choose PSTN Gateway RL > Route Details for PSTN Gateway RL > and enter a Calling Party Transform Mask of 416438XXXX

OR again even more granular

CM > Route Plan > Route Pattern > Find and select the appropriate pattern (for example 9.@ for external calls) > and then input 416438XXXX in the Calling Party Transform Mask

Be careful on where you add it and which method you use. Especially if you doing centralized call processing or toll bypass. You don't want phones in other area codes displaying the 416-438 information when they are actually somewhere else. That is why I think the best bet is method one.

Phew.. I hope this is right. I would always consult Cisco documentation / design guides to make sure that I am not leading you down the wrong road.

None of the suggestions will work if you have restricted IE delivery for outbound calls on the Gateway. On the gateway config page set Display IE delivery for outbound calls to true, set Originator and Allowed. You can also place the DN Mask on the gateway itself but since you probably have more than one g-way you might want to set the mask for the Route Group.

Mask should look like 416438XXXX.

You may also want to check the number of significant digits you are allowing to pass. If it is set lower than 10 you have just shot yourself in the foot. Sig Digits are counted right to left so if you allow 7 then 438XXXX will be passed.

Assuming you are using a PRI, be sure of the following:

In the gateway settings in CallManager, check your numbering plan. Calling party should be national. Calling number plan should be ISDN. Some switches will not display or forward the IE if the numbering plan is "unknown" in Q.931 messages. Also in the Caller ID DN input 416438XXXX and set

Calling Party Selection to Originator. Also Presentation Bit should be Allowed and Display IE should be checked.

Outbound Caller-ID service is only supported in PRI and Feature Group D.

To the best of my knowledge CallManager does not support FGD- only PRI.

Be aware that most Telcos have a "match list" which requires that the outbound number match one they have asigned to that PRI. No match- no caller-id or the main billing number may be sent instead.