•门禁话机功能：全双向、默认自动接听、通过URL/URI远程控制、快速拨号
协议和网络
SIP v1 (RFC2543), v2 (RFC3261)
SIP基于TLS, SRTP
onvif，可绑定外部摄像机
RTSP
TCP/IPv4/UDP
RTP/RTCP, RFC2198, 1889
HTTP/HTTPS/FTP/TFTP
ARP/RARP/ICMP/NTP
DNS SRV/ A Query/NATPR Query
主要、次要 DNS
私网穿透协议, 会话计时器
802.1p/q, DSCP,802.1x
DHCP/Static/PPPoE
DTMF Mode: In-Band, RFC2833 and SIP INFO
