> 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/dnc-blocking.md).

# DNC Blocking

Each DNL Class 4 Fusion switch is integrated directly to DNC database which is updated once a week.  To block calls by DNC, you can go to "Auto Call Block" under Ingress Trunk setting.

![](/files/f6uosUHdpQAHxZ63C0Et)

## Configuring DNC Block

You can then select "Block DNC DNIS" and submit to enable DNC Blocking for this trunk:

![](/files/T5G7rAvurOZeVnT4B3X2)