The GSM Gateway ETS32x16 is a carriergrade VoIP/GSM gateway designed for call centers and telecom operators. It offers 32 ports and supports up to 512 SIM cards (16 SIMs per port) with SIM rotation, BTS (base station) rotation, and auto IMEI change to avoid detection. The gateway includes SBO (bandwidth optimization) and VOS encryption to protect against IP port blocking. It operates on quadband GSM 850/900/1800/1900MHz and can be used for both call termination and origination. The device reduces communication costs by routing international or longdistance calls through local mobile networks. It provides a webbased GUI for easy configuration, realtime call statistics, and CDR export. The ETS32x16 is rackmountable (1U) and ideal for highvolume voice traffic. It supports SIP protocols and can be integrated with softswitches, IPPBX, and other VoIP systems. The gateway is widely deployed in call centers, enterprises, and wholesale voice businesses.