# LERG Blocking

The Telcordia LERG database tells you many information of a phone number and the important data we get for call blocking purposes are : 

* Country of the Phone Number
* Operator Type of the Phone Number ( ex. Wireless, Landline, etc )

You can use the LERG blocking under "Auto Call Block" section in the Ingress Trunk setting to block calls by ANI or DNIS.

![](/files/JvbZCEsSNXbDd7adAgv3)

The selection provided by Class 4 Fusion are as follows:

* Block non US ANI 
* Block Wireless ANI 
* Block Wireless DNIS 
* Block Toll Free ANI 
* Block Invalid +1 ANI
* Whitelist +1 Country for ANI 


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