Hello Users,<br><br>When&nbsp; I tested the OpenSER server&nbsp; with&nbsp; CISCO ATA 186/188 IP phones&nbsp; SIP EyeP media (Softphnoes )&nbsp; is working fine with RTP ,&nbsp; when Both&nbsp; Users and SIP&nbsp; Server&nbsp; is in Behind the NAT,&nbsp; <br><br>But Problem with Softphones ( X-lite ) . 
<br><br>When I ngrep the Calls of X-lite users i didn&#39;t see any Ack Packet to&nbsp; OpenSER&nbsp; After the&nbsp;&nbsp; Invite Packets received . <br><br>Please Help me&nbsp; in this Part<br><br clear="all"><br>-- <br>Thanks and Regards<br>Ravi Prakash Sunkara		
<br><a href="mailto:ravi.sunkara@hyperion-tech.com">ravi.sunkara@hyperion-tech.com</a> 	<br>M:+91 9985077535<br>O:+91 40 23114549<br>F:+91 40 40208727 		<br><a href="mailto:ravi.sunkara@hyperion-tech.com">ravi.sunkara@hyperion-tech.com
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