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is it possible to enable tcp http and websocket all using the same port

is it possible to enable tcp http and websocket all using the same port  using -'node.js,websocket,'

I am trying to enable tcp, http and communication on the same port. I started out with the tcp server (part above //// line), it worked. Then I ran the echo server example found on (part below //// line), it also worked. But when I try to merge them together, tcp doesn't work anymore.

SO, is it possible to enable tcp, http and websockets all using the same port? Or do I have to listen on another port for tcp connections?

var net = require('net');
var http = require('http');
var wsio = require('');

var conn = [];

var server = net.createServer(function(client) {//'connection' listener
    var info = {
        remote : client.remoteAddress + ':' + client.remotePort
    var i = conn.push(info) - 1;
    console.log('[conn] ' + conn[i].remote);

    client.on('end', function() {
        console.log('[disc] ' + conn[i].remote);

    client.on('data', function(msg) {
        console.log('[data] ' + conn[i].remote + ' ' + msg.toString());




var hs = http.createServer(function(req, res) {
    res.writeHead(200, {
        'Content-Type' : 'text/html'
    res.end(['<script>', "var ws = new WebSocket('ws://');", 'ws.onmessage = function (data) { ws.send(data); };', '</script>'].join(''));


var ws = wsio.attach(hs);
var i = 0, last;

ws.on('connection', function(client) {

    var id = ++i, last

    console.log('Client %d connected', id);

    function ping() {
        if (last)
            console.log('Latency for client %d: %d ', id, - last);
        last =;

    client.on('message', ping);



asked Sep 18, 2015 by atulpariharmca
0 votes

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2 Answers

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You can have multiple different protocols handled by the same port but there are some caveats:

  • The must be some way for the server to detect (or negotiate) the protocol that the client wishes to speak. You can think of separate ports as the normal way of detecting the protocol the client wishes to speak.

  • Only one server process can be actually listening on the port. This server might only serve the purpose of detecting the type of protocol and then forwarding to multiple other servers, but each port is owned by a single server process.

  • You can't support multiple protocols where the server speaks first (because there is no way to detect the protocol of the client). You can support a single server-first protocol with multiple client-first protocols (by adding a short delay after accept to see if the client will send data), but that's a bit wonky.

An explicit design goal of the WebSocket protocol was to allow WebSocket and HTTP protocols to share the same server port. The initial WebSocket handshake is an HTTP compatible upgrade request.

The websockify server/bridge is an example of a server that can speak 5 different protocols on the same port: HTTP, HTTPS (encrypted HTTP), WS (WebSockets), WSS (encrypted WebSockets), and Flash policy response. The server peaks at the first character of the incoming request to determine if it is TLS encrypted (HTTPS, or WSS) or whether it begins with "<" (Flash policy request). If it is a Flash policy request, then it reads the request, responds and closes the connection. Otherwise, it reads the HTTP handshake (either encrypted or not) and the Connection and Upgrade headers determine whether it is a WebSocket request or a plain HTTP request.

Disclaimer: I made websockify

answered Sep 18, 2015 by thiru
0 votes

Short answer - NO, you can't have different TCP/HTTP/Websocket servers running on the same port.

Longish answer - Both websockets and HTTP work on top of TCP. So you can think of a http server or websocket server as a custom TCP server (with some state mgmt and protocol specific encoding/decoding). It is not possible to have multiple sockets bind to the same port/protocol pair on a machine and so the first one will win and the following ones will get socket bind exceptions.

answered Sep 18, 2015 by amit.gupta