1,GOIP_8 / gsm goip gateway 8 cahnnels goip gateway 2 NAT transvesal 3,VLAN and QoS 4.SIP/H. ... 323 5.support IMEI change 8 channels goip gateway/gsm goip gateway 8(GOIP_8) Specification:1. 4 GSM channels,up to ... furtherinformation,please feel free to contact me. 8 channels goip gateway/gsm goip gateway 8(GOIP_8)