By Alok Saboo on March 24th, 2010
Although VoIP is a great technology and greatly benefits consumers, some middle-eastern countries such as UAE, Dubai, Oman, and Belize have restricted the access to VoIP. Even in countries which are generally fairly unrestrictive in Internet access, some ISPs restrict access to certain aspects (VoIP being one of them). The common approach to restrict access to VoIP is to block the common ports (e.g., 5060) used by VoIP soft phone (e.g., X-lite) or hardware (ATA) to transmit data. Needless to say, this causes great inconvenience to the users. Since the Ringomax service has been having difficulties bypassing ISP ban, here’s a simple tutorial to bypass the ISP restrictions on VoIP calls.
What is the underlying problem?
Before I provide the solution, it would be instructive to go over the underlying problem. Since your ISP has blocked the SIP ports (e.g., 5060), your VoIP device (hardware or software) cannot communicate with the VoIP server and hence you may not be able to use VoIP entirely or in some cases the other party may not hear you (one way audio).
Solution to get around the ISP restriction
A simple approach to get around this restriction would be use some other port to transmit VoIP data; most likely your ISP will not block all the ports. FreeSPS provides an outbound proxy server that you can use to transmit your SIP data. Currently, you can use the following servers (but please check their website for the working outbound proxy servers):
Just enter one of these in your Outbound Proxy server field and (hopefully) that should help your cause. If one port is not working, try some other port, e.g., your ISP may have blocked port 53, but port 1812 may still be open. To find out which port is open, you can use the “netstat –a” command in the command prompt. Open ports should have status “Listening” or “Established”. If you are not familiar with how to configure the outbound proxy in your SIP client, follow the instructions in the next section.
Configuring your SIP client using Outbound Proxy
To configure the above proxy server in your SIP client, you can follow our tutorial on configuring SIP accounts in x-lite half way. Instead of the proxy us.voxalot.com in the screenshot, just enter the proxy that you want to use (e.g., free.sipout.com:1812). It should look something like this:
Don’t be confused with the different color than the earlier post, this is the latest version of x-lite. The fields and the other details remain the same. You can find the SIP settings of Betamax providers (e.g., Rynga, ActionVoIP, SmartVoIP, Jumblo) here.
If you are using an ATA, the field may be labeled “Outbound Proxy”. Also, make sure that you enable “Use Outbound Proxy” so that your ATA actually uses the proxy.
Update: Also read how to make low cost VoIP calls using Miglu even if blocked by your ISP.
Disclaimer: This article is purely educational. Please consult your local regulations for specific, localized situations.