> For the complete documentation index, see [llms.txt](https://cookbook.denovolab.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cookbook.denovolab.com/automatic-call-blocking/lerg-blocking.md).

# 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