目前，包括我国在内的许多国家都采用了H.323作为IP电话网关之间的协议，整个IP电话系统只是把IP网络作为传输媒介，在用户的接入上还是采用电路交换系统，把IP电话网关作为电路交换网和IP网络的接口。
Currently, including China, many countries had adopted H.323 IP telephony gateway as the agreement between the the entire IP phone system is to bring the IP network as a transmission medium, the user's access or use on circuit-switched systems, IP Telephony as a circuit-switched network and IP network interface. (2006-05-19, Asm, 577KB, 下载11次)