This was an interesting scenario where this customer called and said that when calls are getting forwarded from their IP Phones to their mobile phones, they are not getting the Original Calling party number and instead getting their office main line number. This was happening for two different sites for this customer.
External Calling Party (1189765676) ===> PSTN === > Gateway ===> CUCM === >IP phone (3456) || CFWdall 9078XXXXXXXX || ==> Dials out === > Reach Mobile Phone === > CLI getting as 9784567000 (Company main line number) instead of 1189765676.
This is a normal Call manager behavior. As the call is getting forwarded from the IP phone, the call manager takes the ANI from its system and sends the call over the PSTN as a new call.
The only way we can have the calling party number displayed on a forwarded call is to use Cisco Mobile Connect which is also called SNR (Single number reach). I will discuss this feature later in this blog.