Asterisk is PBX server for VOIP communication. It uses various protocols, some of which are SIP, RTP, SRTP.
There are a few ways to connect an asterisk server with the traditional PSTN network: * asterisk_chan_dongle: A channel driver that bridges to Huawei USB dongles * asterisk_chan_quectel: A channel driver for quectel devices and SIM7600
Airtel use VOIP for landline connection via it’s modem devices: * [Airtel SIP log](wtex)❌