title: sftp connection over esp8266 module
body: <p>I am trying to make a sftp connection using esp8266 wifi module but I am facing problems. First I successfully connected esp8266 to my router then I tried making tcp connection to sftp server by using following command</p>
  
  <pre><code>AT+CIPSTART="TCP","demo@test.rebex.net",22
  </code></pre>
  
  <p>but I always get "DNS FAIL" reply from esp8266. How can I make a sftp connection using esp8266 wifi module?</p>