title: Twilio: Dial extension number along with twilio number
body: <p>I am using Twilio for inbound calls, where user can call an application through Twilio-Number (brought from Twilio) and will be redirected to admin.</p>
  
  <p>Now, We want Admin to call User using same Twilio-Number. We wabt to call this as <code>&lt;Twilio_Number&gt;#&lt;user_id&gt;</code>. We want to pass <code>&lt;user_id&gt;</code> as extension, so that when Admin clicks on the link with <code>tel=&lt;Twilio_Number&gt;#&lt;user_id&gt;</code>, it will initiate a phone-call to twilio-number. </p>
  
  <p>In our app, we will find user's mobile using his id and redirect call to user's mobile number.</p>
  
  <p>I have referred this doc: <a href="https://www.twilio.com/docs/howto/companydirectory" rel="noreferrer">https://www.twilio.com/docs/howto/companydirectory</a></p>
  
  <p>But would need few more details like:</p>
  
  <p>How will Twilio recognize the extension number? And by which name is it provided in call-request parameters?</p>
  
  <p>Currently, we received these parameters in twilio-voice call request
  <code>CallSid</code>, <code>AccountSid</code>, <code>ApiVersion</code>, <code>Direction</code>, <code>To</code>, <code>Called</code>, <code>Caller</code>, <code>From</code>. In the same request-parameters, how I can get extension digits?</p>
  
  <p>Thanks.</p>