diff --git a/package.json b/package.json
index 258331e..ea670dc 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,8 @@
   "main": "server.js",
   "directories": {},
   "scripts": {
-    "test": "echo \"No tests needed!\" && exit 1"
+    "test": "echo \"No tests needed!\" && exit 1",
+    "server": "node server.js"
   },
   "repository": {
     "type": "git",
diff --git a/public/js/main.js b/public/js/main.js
index c2965ad..fad2a96 100644
--- a/public/js/main.js
+++ b/public/js/main.js
@@ -1,7 +1,9 @@
 var whiteboardId = getQueryVariable("whiteboardid");
 whiteboardId = whiteboardId || "myNewWhiteboard";
 var myUsername = getQueryVariable("username");
+var accessToken = getQueryVariable("accesstoken");
 myUsername = myUsername || "unknown" + (Math.random() + "").substring(2, 6);
+accessToken = accessToken || "";
 
 var url = document.URL.substr(0, document.URL.lastIndexOf('/'));
 var signaling_socket = null;
@@ -27,7 +29,11 @@ signaling_socket.on('connect', function () {
         whiteboard.refreshUserBadges();
     });
 
-    signaling_socket.emit('joinWhiteboard', whiteboardId);
+    signaling_socket.on('wrongAccessToken', function () {
+        alert("Access denied! Wrong accessToken!")
+    });
+
+    signaling_socket.emit('joinWhiteboard', { wid : whiteboardId, at : accessToken });
 });
 
 $(document).ready(function () {
@@ -35,12 +41,13 @@ $(document).ready(function () {
         whiteboardId: whiteboardId,
         username: myUsername,
         sendFunction: function (content) {
+            content["at"] = accessToken;
             signaling_socket.emit('drawToWhiteboard', content);
         }
     });
 
     // request whiteboard from server
-    $.get(subdir + "/loadwhiteboard", { wid: whiteboardId }).done(function (data) {
+    $.get(subdir + "/loadwhiteboard", { wid: whiteboardId, at : accessToken }).done(function (data) {
         whiteboard.loadData(data)
     });
 
@@ -221,7 +228,8 @@ function uploadImgAndAddToWhiteboard(base64data) {
         data: {
             'imagedata': base64data,
             'whiteboardId': whiteboardId,
-            'date': date
+            'date': date,
+            'at' : accessToken
         },
         success: function (msg) {
             var filename = whiteboardId + "_" + date + ".png";
diff --git a/server.js b/server.js
index 24291be..c10b3a8 100644
--- a/server.js
+++ b/server.js
@@ -1,4 +1,5 @@
 var PORT = 8080; //Set port for the app
+var accessToken = ""; //Can be set here or as start parameter (node server.js --accesstoken=MYTOKEN)
 
 fs = require("fs-extra");
 var express = require('express');
@@ -12,11 +13,25 @@ server.listen(PORT);
 var io = require('socket.io')(server);
 console.log("Webserver & socketserver running on port:"+PORT);
 
+var startArgs = getArgs ();
+if(startArgs["accesstoken"]) {
+    accessToken = startArgs["accesstoken"];
+}
+if(accessToken!=="") {
+    console.log("AccessToken set to: "+accessToken);
+}
+
 app.get('/loadwhiteboard', function(req, res) {
     var wid = req["query"]["wid"];
-    var ret = s_whiteboard.loadStoredData(wid);
-    res.send(ret);
-    res.end();
+    var at = req["query"]["at"]; //accesstoken
+    if(accessToken==="" || accessToken==at) {
+        var ret = s_whiteboard.loadStoredData(wid);
+        res.send(ret);
+        res.end();
+    } else {
+        res.status(401);  //Unauthorized
+        res.end();
+    }
 });
 
 app.post('/upload', function(req, res) { //File upload
@@ -39,8 +54,13 @@ app.post('/upload', function(req, res) { //File upload
     });
 
     form.on('end', function() {
-        progressUploadFormData(formData);
-        res.send("done");
+        if(accessToken==="" || accessToken==formData["fields"]["at"]) {
+            progressUploadFormData(formData);
+            res.send("done");
+        } else {
+            res.status(401);  //Unauthorized
+            res.end();
+        }
         //End file upload
     });
     form.parse(req);
@@ -82,12 +102,21 @@ io.on('connection', function(socket){
 
     socket.on('drawToWhiteboard', function(content) {
         content = escapeAllContentStrings(content);
-        socket.broadcast.to(content["wid"]).emit('drawToWhiteboard', content); //Send to all users in the room (not own socket)
-        s_whiteboard.handleEventsAndData(content); //save whiteboardchanges on the server
+        if(accessToken==="" || accessToken==content["at"]) {
+            socket.broadcast.to(content["wid"]).emit('drawToWhiteboard', content); //Send to all users in the room (not own socket)
+            s_whiteboard.handleEventsAndData(content); //save whiteboardchanges on the server
+        } else {
+            socket.emit('wrongAccessToken', true);
+        }     
     });
 
-    socket.on('joinWhiteboard', function(wid) {
-        socket.join(wid); //Joins room name=wid
+    socket.on('joinWhiteboard', function(content) {
+        content = escapeAllContentStrings(content);
+        if(accessToken==="" || accessToken==content["at"]) {
+            socket.join(content["wid"]); //Joins room name=wid
+        } else {
+            socket.emit('wrongAccessToken', true);
+        }
     });
 });
 
@@ -107,4 +136,25 @@ function escapeAllContentStrings(content, cnt) {
         }
     }
     return content;
-}
\ No newline at end of file
+}
+
+function getArgs () {
+    const args = {}
+    process.argv
+      .slice(2, process.argv.length)
+      .forEach( arg => {
+        // long arg
+        if (arg.slice(0,2) === '--') {
+          const longArg = arg.split('=')
+          args[longArg[0].slice(2,longArg[0].length)] = longArg[1]
+        }
+       // flags
+        else if (arg[0] === '-') {
+          const flags = arg.slice(1,arg.length).split('')
+          flags.forEach(flag => {
+            args[flag] = true
+          })
+        }
+      })
+    return args
+  }
\ No newline at end of file