Astercon2 is an open source Linux-based softswitch + IPPBX + digital/analog relay system. It integrates the best technologies under Linux, Asterisk, Perl, and Webserver, to realize registration management, billing, card issuance, direct dialing, and callback, and 100% supports ISDN PRI and ANALOG hardware boards.
Astercon adopts a bilingual design in Chinese and English, and is designed to support more languages in the future, and Astercon is a relatively simple system to install.
Astercon2 is not as functional as FreePBX (for now), but it has integrated a billing system and can implement billing operations with simple settings, saving you valuable time and energy. Because the underlying architecture directly uses Asterisk, as long as you are familiar with Asterisk, you can implement the functions you need on Astercon2.
Colorless humor note: Astercon2 is a VOIP operation system. The VOIP operation systems currently on the market often cost tens of thousands or hundreds of thousands, which is normal. However, Astercon2 is a free, open source system with a Chinese interface.