title: What are the equivalent of TCP Client and TCP Server for Swift
body: <p>Hi I am a newbie in iOS and Swift. I did some search on internet and i could not find a definite answer to my quest. I found socket.io but this is web socket. </p>
  
  <p>Can you help and tell me the equivalent of TCP Client and TCP server for iOS for Swift 3. </p>
  
  <p>I have these questions</p>
  
  <p>If I use the iOS-base equivalent TCP client to send a message to server</p>
  
  <p>1) On server-side, can I use other TCP Server to return message? any issue?</p>
  
  <p>Thanks</p>