diff --git a/client.js b/client.js
index 839635f9..b4b3d8ec 100644
--- a/client.js
+++ b/client.js
@@ -42,6 +42,19 @@ const command = process.argv[2];
 // and as the process name in ps/top on linux.
 process.title = "clusterioClient "+instance;
 
+// make sure we have the master access token (can't write to master without it since clusterio 2.0)
+if(!config.masterAuthToken || typeof config.masterAuthToken !== "string"){
+	console.log("ERROR invalid config!");
+	console.log("Master server now needs an access token for write operations. As clusterio slaves depends \
+	upon this, please add your token to config.js in the field named masterAuthToken. \
+	You can retrieve your auth token from the master in secret-api-token.txt after running it once.");
+}
+const needleOptionsWithTokenAuthHeader = {
+	headers: {
+		'x-access-token': config.masterAuthToken
+	},
+};
+
 var instanceInfo = {};
 
 // function to handle sending commands into the game
@@ -604,7 +617,7 @@ function instanceManagement() {
 					} else {
 						payload.mac = mac
 						console.log("Registered our precense with master "+config.masterIP+" at " + payload.time);
-						needle.post(config.masterIP + ":" + config.masterPort + '/api/getID', payload, function (err, response, body) {
+						needle.post(config.masterIP + ":" + config.masterPort + '/api/getID', payload, needleOptionsWithTokenAuthHeader, function (err, response, body) {
 							if (err && err.code != "ECONNRESET"){
 								console.error("We got problems, something went wrong when contacting master");
 								console.error(err);
@@ -637,7 +650,7 @@ function instanceManagement() {
 				modName: modHashes[i].modName,
 				hash: modHashes[i].hash,
 			}
-			needle.post(config.masterIP + ":" + config.masterPort + '/api/checkMod', payload, function (err, response, body) {
+			needle.post(config.masterIP + ":" + config.masterPort + '/api/checkMod', payload, needleOptionsWithTokenAuthHeader, function (err, response, body) {
 				if(err) console.log(new Error("Unable to contact master server! Please check your config.json."));
 				if(response && body && body == "found") {
 					console.log("master has mod");
@@ -647,7 +660,11 @@ function instanceManagement() {
 						console.log("Sending mod: " + mod);
 						// Send mods master says it wants
 						// response.body is a string which is a modName.zip
-						var req = request.post("http://"+config.masterIP + ":" + config.masterPort + '/api/uploadMod', function (err, resp, body) {
+						var req = request.post({url: "http://"+config.masterIP + ":" + config.masterPort + '/api/uploadMod',
+							headers: {
+								"x-access-token": config.masterAuthToken,
+							},
+						}, function (err, resp, body) {
 							if (err) {
 								console.log(new Error("Unable to contact master server! Please check your config.json."));
 							} else {
@@ -705,7 +722,7 @@ function instanceManagement() {
 						}
 					}
 					console.log("Recorded flows, copper plate since last time: " + payload["copper-plate"]);
-					needle.post(config.masterIP + ":" + config.masterPort + '/api/logStats', {timestamp: timestamp, instanceID: instanceconfig.unique,data: payload}, function (err, response, body) {
+					needle.post(config.masterIP + ":" + config.masterPort + '/api/logStats', {timestamp: timestamp, instanceID: instanceconfig.unique,data: payload}, needleOptionsWithTokenAuthHeader, function (err, response, body) {
 						// we did it, keep going
 					});
 				}
@@ -737,7 +754,7 @@ function instanceManagement() {
 					count: g[1],
 					instanceName: instance, // name of instance
 					instanceID: instanceconfig.unique, // a hash computed from the randomly generated rcon password
-				}, function (err, resp, body) {
+				}, needleOptionsWithTokenAuthHeader, function (err, resp, body) {
 					if(body == "failure") console.error("#### Export failed! Lost: "+g[1]+" "+g[0]);
 					if(config.logItemTransfers){
 						if(body == "success") console.log(`Exported ${g[1]} ${g[0]} to master`);
@@ -794,7 +811,7 @@ function instanceManagement() {
 			// request our items, one item at a time
 			for (let i = 0; i < Object.keys(preparedPackage).length; i++) {
 				// console.log(preparedPackage[Object.keys(preparedPackage)[i]]);
-				needle.post(config.masterIP + ":" + config.masterPort + '/api/remove', preparedPackage[Object.keys(preparedPackage)[i]], function (err, response, body) {
+				needle.post(config.masterIP + ":" + config.masterPort + '/api/remove', preparedPackage[Object.keys(preparedPackage)[i]], needleOptionsWithTokenAuthHeader, function (err, response, body) {
 					if (response && response.body && typeof response.body == "object") {
 						// buffer confirmed orders
 						confirmedOrders[confirmedOrders.length] = {
diff --git a/lib/authenticate.js b/lib/authenticate.js
new file mode 100644
index 00000000..b13404c5
--- /dev/null
+++ b/lib/authenticate.js
@@ -0,0 +1,15 @@
+const jwt = require('jsonwebtoken');
+
+const config = require("./../config");
+
+var middleware = function (req, res, next) {
+	var token = req.headers['x-access-token'];
+	if(!token) return res.status(401).send({ auth: false, message: 'No token provided.', endpoint: req.route.path});
+	
+	jwt.verify(token, config.masterAuthSecret, function(err, decoded) {
+		if(err) return res.status(500).send({ auth: false, message: 'Failed to authenticate token.', endpoint: req.route.path});
+		next();
+	});
+}
+
+module.exports = {middleware};
diff --git a/master.js b/master.js
index d8cb67da..f7831405 100644
--- a/master.js
+++ b/master.js
@@ -28,6 +28,9 @@ var config = require('./config');
 const getFactorioLocale = require("./lib/getFactorioLocale");
 const stringUtils = require("./lib/stringUtils");
 
+// homemade express middleware for token auth
+const authenticate = require("./lib/authenticate");
+
 // Library for create folder recursively if it does not exist
 const mkdirp = require("mkdirp");
 mkdirp.sync("./database");
@@ -37,8 +40,13 @@ const deepmerge = require("deepmerge");
 const path = require("path");
 const fs = require("fs");
 const nedb = require("nedb");
+
 const jwt = require('jsonwebtoken');
 const bcrypt = require('bcryptjs');
+// write an auth token to file
+fs.writeFileSync("secret-api-token.txt", jwt.sign({ id: "api" }, config.masterAuthSecret, {
+	expiresIn: 86400*365 // expires in 1 year
+}));
 
 const express = require("express");
 const ejs = require("ejs");
@@ -224,7 +232,7 @@ POST World ID management. Slaves post here to tell the server they exist
 @instance
 @alias /api/getID
 */
-app.post("/api/getID", function(req,res) {
+app.post("/api/getID", authenticate.middleware, function(req,res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	// request.body should be an object
@@ -253,7 +261,7 @@ POST Allows you to add metadata related to slaves for other tools, like owner da
 @instance
 @alias /api/editSlaveMeta
 */
-app.post("/api/editSlaveMeta", function(req,res) {
+app.post("/api/editSlaveMeta", authenticate.middleware, function(req,res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	// request.body should be an object
@@ -292,22 +300,6 @@ app.post("/api/getSlaveMeta", function (req, res) {
     	res.send('{"INVALID REQUEST":1}');
 	}
 });
-// TODO: Remove deprecated function, also update researchSync to not use it
-/**
-POST DEPRECATED Get metadata from all slaves. This is already covered by /api/slaves, please use that one instead.
-@memberof clusterioMaster
-@instance
-@alias /api/getSlavesMeta
-*/
-app.post("/api/getSlavesMeta", function (req, res) {
-    if(req.body.password){
-    	let metas = {};
-        res.send(JSON.stringify(Object.keys(slaves).map(key => metas[key] = slaves[key].meta)));
-    } else {
-        res.status(400);
-        res.send('{"INVALID REQUEST":1}');
-    }
-});
 // mod management
 // should handle uploading and checking if mods are uploaded
 /**
@@ -341,7 +333,7 @@ POST endpoint for uploading mods to the master server. Required for automatic mo
 @instance
 @alias /api/uploadMod
 */
-app.post("/api/uploadMod", function(req,res) {
+app.post("/api/uploadMod", authenticate.middleware, function(req,res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	if (!req.files) {
@@ -398,7 +390,7 @@ POST endpoint for storing items in master's inventory.
 @param {string} [itemStack.instanceName="unknown"] the name of an instance for identification in statistics, as provided when launching it. ex node client.js start [name]
 @returns {string} status either "success" or "failure"
 */
-app.post("/api/place", function(req, res) {
+app.post("/api/place", authenticate.middleware, function(req, res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	res.header("Access-Control-Allow-Origin", "*");
@@ -465,7 +457,7 @@ POST endpoint to remove items from DB when client orders items.
 @returns {itemStack} the number of items actually removed, may be lower than what was asked for due to shortages.
 */
 _doleDivisionFactor = {}; //If the server regularly can't fulfill requests, this number grows until it can. Then it slowly shrinks back down.
-app.post("/api/remove", function(req, res) {
+app.post("/api/remove", authenticate.middleware, function(req, res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	const doleDivisionRetardation = 10; //lower rates will equal more dramatic swings
@@ -540,7 +532,7 @@ Gives no response
 @param {object} circuitFrame
 @param {number} circuitFrame.time
 */
-app.post("/api/setSignal", function(req,res) {
+app.post("/api/setSignal", authenticate.middleware, function(req,res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	if(typeof req.body == "object" && req.body.time){
@@ -625,7 +617,7 @@ course the timeSeries data.
 @param {object} JSON {timestamp: Date.now(), instanceID: "string", data: {"item": number}}
 @returns {string} failure
 */
-app.post("/api/logStats", function(req,res) {
+app.post("/api/logStats", authenticate.middleware, function(req,res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	let reqStartTime = Date.now();
 	if(typeof req.body == "object" && req.body.instanceID && req.body.timestamp && req.body.data) {
@@ -793,10 +785,6 @@ Requires x-access-token header to be set. Find you api token in secret-api-token
 @param {object} JSON {instanceID:19412312, command:"/c game.print('hello')"}
 @returns {object} Status {auth: bool, message: "Informative error", data:{}}
 */
-// write an auth token to file
-fs.writeFileSync("secret-api-token.txt", jwt.sign({ id: "api" }, config.masterAuthSecret, {
-	expiresIn: 86400*365 // expires in 1 year
-}));
 app.post("/api/runCommand", (req,res) => {
 	var token = req.headers['x-access-token'];
 	if(!token) return res.status(401).send({ auth: false, message: 'No token provided.' });