原文链接：
1. 这里以 Debian 为例子，安装 Asterisk
apt-get update apt-get install asterisk
2. 预设置 Asterisk，修改 sip.conf 和 extensions.conf 文件，是为了创建两个可供测试的 SIP 账号
nano /etc/asterisk/sip.conf
在文件的开头部分添加如下信息：
[general] context = default bindport = 5060 bindaddr = 0.0.0.0 tcpbindaddr = 0.0.0.0 tcpenable = yes [1001] type = friend callerid = User One secret = 1001 host = dynamic canreinvite = no dtmfmode = rfc2833 mailbox = 1001 disallow = all allow = ulaw transport = udp [1002] type = friend callerid = User Two secret = 1002 host = dynamic canreinvite = no dtmfmode = rfc2833 mailbox = 1002 disallow = all allow = ulaw transport = udp<