> 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/introduction.md).

# Introduction

DNL Class 4 Fusion provides many mechanism for operators to block unwanted traffic based on the ANI and DNIS.  In addition to simple prefix type blocking, DNL also gain access to multiple industry database including Youmail, DNC, FTC, and LERG as a well to block unwanted traffic for operators.