title: SIP RTP Stack for IVR Application
body: <p>I have an IVR application which plays the prompts and records the user message and detects the DTMF. Currently the application is based on SS7 signaling and uses the PSTN based media boards for media play / record functionality.</p>
  
  <p>Now I have to move this application to IP based solution. For this, I need any open-source / low-cost solution to enable SIP based signaling and RTP based media flow and G.711 encoding / decoding and support for Windows and Linux.</p>
  
  <p>My application needs to handle around 500 concurrent calls, and the code is closed code so cannot be GPL'ed. I will prefer LGPL code. </p>
  
  <p>I have shortlisted few solutions:</p>
  
  <ol>
  <li>OSIP(LGPL) + ORTP(LGPL) + eXosip(GPL)</li>
  <li>PJSIP + PJMEDIA (GPL / Licensed)</li>
  <li>Radvision (Too costly).</li>
  </ol>
  
  <p>Please suggest me what is the best option among these or else let me know if any other better option is available.</p>
  
  <p>GJ</p>