Below are some frequent questions we are asked about SIP/VoIP
I have one-way audio – IP routing issue, check firewall settings and ports.
SIP telephone will not register/provision – IP routing issue, can you ping the provisioning server?
Call quality or lost audio problems – Traffic issues, your ISP may be busy or having issues www.speedtest.net
Buzzing on the line – Caused by analogue devices, faulty cable/adapter or ATA.
Echo during calls – Reconnect call, if problem continues possible traffic issues (see above).
Here are some basic firewall configuration settings for SIP/VoIP
Most SIP/VoIP telephony providers have specific ports and settings that may need altering on your firewall.
The following are common firewall ports and settings that are needed for most SIP/VoIP communications providers:
TCP – 80
TCP – 443
UDP – 10000 to 60000
UDP – 53
UDP – 123
TCP & UDP – 5060 & 5062
SIP ALG Disabled
Always check with your SIP provider to confirm the correct firewall configuration required for your SIP/VoIP telephone.
Most good hosted telephony providers also offer further support for configuring and provisioning your SIP/VoIP telephone on their hosted telephony service.