[Serusers] doubts about nathelper

I'm having trouble in using STUN with some UserAgents, which are not nat friendly at all. So, I've been reading about nathelper, but I did not find how does it work or how do I need to configure my ser.cfg to have this solution implemented. I'd like to know what it the function theory of nathelper (not about its code, but yes how does it work) and how should I need to touch my ser.cfg and also how to configure my UserAgent. Will nathelper help me with ANY UserAgent behind a NAT, no matter what kind of nat am I using and no matter whether my nat preserves or not the udp ports for the rtp connection ?? Does NAThelper impacts in the quality of the communication (QoS) ? Is NATHelper an outboundproxy ? Is NATHelper a session-border-controller ? The thing is I'm telling my UserAgent to use some XXX rtp port, but, automagically (ufff) my linksys changes the port, and so I get one-way audio. I need to solve this urgently. It gets worse if I have many UserAgents behind this nat. I've also noticed that when broadband router (d-link) does not preserve ports, and assigns them randomly, whenever the link to internet goes down and up again, my UserAgent needs to talk again with STUN to find out its port. Just a mess !!! Hope you can help me out in getting to know nathelper and configuring it. Thanx in advance Regards, Lucas -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.8.4 - Release Date: 01/02/2005