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Unread 03-19-2009, 07:25 PM   #3
carlosalbffgomes
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Default Possible solutions

Issues reported on these posts are probably NAT/Firewall problems. The exact solution depends of some unknown factors such as modem/router configurations, but there are several things that can be tested if you have the necessary technical skills:

1. You can put the IP Phone/ATA on the DMZ (this is a modem/router configuration option). Some says that problems can arise on the intranet side (your private network) with such configuration, but it depends on what you use and your technical skills (I personally have used this kind of configuration with no problems with one IP Phone and two computers running exclusively Linux OS). Never the less, this is something you can try to see if it works. If so, then the problem is really from your side (your modem/router NAT/firewall). You should also configure the IP Phone/ATA passwords to user and admin users so no one can easily change your phone configuration from the internet side.

2. Using an Voxalot Premium account you register your VSP with Voxalot. Set the 'Symmetric NAT Handling' to 'Yes' on the member details page and set to 'No' the 'Optimize Audio Path' option on your Voice Service Provider configuration. With this kind of configuration it should work. In this case you don't redirect your provider to sip:xxxxxx@voxalot.com!

3. More difficult but possible: try to disable the router firewall (some routers have NAT+Firewall) and forward IP Ports assigned on your IP Phone/ATA configuration to the RTP stream. Also you could set the 'Symmetric RTP' option to 'Yes' on the Linksys IP Phone/ATA. This kind of configuration can (and it should) work, but I think is the more difficult one to implement if you are not technically skilled.

If you can understand these suggestions and have the necessary skills to implement them, then you may resolve the one-way audio problem.

Regards,

Last edited by carlosalbffgomes; 03-19-2009 at 10:21 PM.
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