Recently we found that O2's TU go application that uses the internet to make and receive calls kept on crashing out after installing an enterprise level security system in Draytek's Vigor firewalls.
Luckily our technicians knew what the problem was straight away.
Luckily our technicians knew what the problem was straight away.
TU go is O2's version of a VOIP / SIP based telephony technology that makes your calls over an internet connection, instead of the standard cell phone towers. The problem is that a Draytek Vigor has it's Session Initiation Protocol (SIP) Application Layer Gateway (ALG) defence enabled by default. This will interfere with SIP and can affect your VOIP functionality across all devices. The solution is to disable SIP ALG on the Vigor itself.
To disable SIP ALG, please follow the below guide:
- Make sure you know the IP address of your device. The default IP is 192.168.1.1
- In windows open up a command prompt with telnet enabled, or use the program putty from http://www.putty.org to establish a telnet connection to the Vigor. If you are using an Apple Mac or Linux machine, please open a terminal window.
- Enter the folowing: telnet 192.168.1.1 putty has a slightly different interface and beyond the scope of this guide
- Once connected you will be prompted for the username, by default enter admin
- You will now be prompted for the password, enter the admin password
- To see the current status of SIP ALG enter the following: sys sip alg ?
- To disable SIP ALG enter: sys sip alg 0
- Commit the changes and then reboot by typing: sys commit
- Reboot: sys reboot
- After reboot, you can log back on to the device via telnet and confirm the changes by entering: sys sip alg ?
After this change was made, the O2 Tu go software has become more stable and the calls a lot clearer.
Let us know your thoughts and contributions, or if this has helped you out.
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Let us know your thoughts and contributions, or if this has helped you out.
Your feedback is important to us.