上周末，我发现FreePBX到中国电信IMS服务器的chan_pjsip中继出现问题，电话呼入遇忙音或报网络问题。经过一番抓包分析后，我用回了chan_sip中继。我估计中国电信近期对IMS服务器作过系统升级，导致跟Asterisk 13 pjsip中继之间的对称SIP/RTP信令的匹配问题。不过，最新版的MicroSIP软电话仍能匹配，电话呼入和呼出都没问题。
要使用chan_sip中继，须在EPON网关上为chan_sip绑定的端口号设置端口转发。
Setup port forwarding on the voice network interface of the epon home gateway
The voice network interface on the epon gateway is 1_VOICE_INTERNET_R_VID_46 (epon0.4).
Note: chan_sip binds to the non-default SIP port 5160 in FreePBX.
| 服务器名 | 外部初始端口 | 外部终止端口 | 协议 | 内部初始端口 | 内部终止端口 | 服务器IP地址 | WAN接口 |
|---|---|---|---|---|---|---|---|
| SIP | 5160 | 5160 | UDP | 5160 | 5160 | 192.168.1.2 | epon0.4 |
Create a chan_sip trunk in FreePBX
- General:
- Trunk Name: CTC
- Outbound Caller ID: 0216XXXXXXX
- sip Settings:
- Outgoing:
- Trunk Name: CTC
- PEER Details:
host=15.192.XX.XX
username=+86216XXXXXXX@sh.ctcims.cn
secret=xxxxxx
type=peer
keepalive=30
insecure=port,invite
fromuser=+86216XXXXXXX
fromdomain=sh.ctcims.cn
context=from-trunk
dtmfmode=auto
- Incoming:
- Register String:
+86216XXXXXXX@sh.ctcims.cn:xxxxxx:+86216XXXXXXX@sh.ctcims.cn@15.192.XX.XX
- Register String:
- Outgoing:
Asterisk SIP Settings
- General SIP Settings
- NAT Settings
- External Address: 28.XX.XX.XXX (IP address of epon0.4)
- Local Networks: 192.168.0.0/16
- NAT Settings
- Chan SIP Settings
- NAT Settings
- NAT: yes
- IP Configuration: Static IP
- Registration Settings
- Registration Minimum Expiry: 1500
- Registration Default Expiry: 1500
- NAT Settings
Updates
2020-06-15
- Pressing number keys doesn't work with IVR systems. Add
dtmfmode=autoto "PEER Details" to resolve the issue.