<div dir="ltr">On further testing, using the IP address instead of the domain name in the URI setting of Linphone works with TCP, so I think this might be to do with SRV/NAPTR records associated with the domain.</div><div class="gmail_extra"><br><div class="gmail_quote">On 31 January 2016 at 08:29, Nabeel <span dir="ltr"><<a href="mailto:nabeelshikder@gmail.com" target="_blank">nabeelshikder@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><span style="font-size:12.8px">Hello,</span><div style="font-size:12.8px"><br></div><div style="font-size:12.8px">There seems to be a problem with calls over TCP using Linphone, and since Linphone is a popular open source application, I would like someone to please verify this problem. Calls work fine with Linphone over UDP, but after registering with TCP using the same credentials, calls do not connect at all and lead to a request timeout. A request timeout does not say much about the cause, but in this case I suspect there is something wrong with TCP on the server side. I would like someone to please install Linphone on your phone and connect to your OpenSIPS server using UDP and TCP. Please report here if the calls work over both transports. </div></div>
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