diff --git a/app/src/RoomClient.js b/app/src/RoomClient.js
index 4edc5c3..3188526 100644
--- a/app/src/RoomClient.js
+++ b/app/src/RoomClient.js
@@ -391,7 +391,7 @@ export default class RoomClient
 
 	login()
 	{
-		const url = `/auth/login?id=${this._peerId}`;
+		const url = `/auth/login?peerId=${this._peerId}&roomId=${this._roomId}`;
 
 		window.open(url, 'loginWindow');
 	}
diff --git a/server/config/config.example.js b/server/config/config.example.js
index ee225b1..5c7291d 100644
--- a/server/config/config.example.js
+++ b/server/config/config.example.js
@@ -52,12 +52,13 @@ module.exports =
 	// use case: loadbalancer backend
 	httpOnly              : false,
 	// This function will be called on successful login through oidc.
-	// Use this function to map your oidc userinfo to the Peer object,
-	// see examples below.
+	// Use this function to map your oidc userinfo to the Peer object.
+	// The roomId is equal to the room name.
+	// See examples below.
 	// Examples:
 	/*
 	// All authenicated users will be MODERATOR and AUTHENTICATED
-	userMapping : async ({ peer, userinfo }) =>
+	userMapping : async ({ peer, roomId, userinfo }) =>
 	{
 		peer.addRole(userRoles.MODERATOR);
 		peer.addRole(userRoles.AUTHENTICATED);
@@ -65,7 +66,7 @@ module.exports =
 	// All authenicated users will be AUTHENTICATED,
 	// and those with the moderator role set in the userinfo
 	// will also be MODERATOR
-	userMapping : async ({ peer, userinfo }) =>
+	userMapping : async ({ peer, roomId, userinfo }) =>
 	{
 		if (
 			Array.isArray(userinfo.meet_roles) &&
@@ -88,7 +89,7 @@ module.exports =
 	// All authenicated users will be AUTHENTICATED,
 	// and those with email ending with @example.com
 	// will also be MODERATOR
-	userMapping : async ({ peer, userinfo }) =>
+	userMapping : async ({ peer, roomId, userinfo }) =>
 	{
 		if (userinfo.email && userinfo.email.endsWith('@example.com'))
 		{
@@ -96,8 +97,21 @@ module.exports =
 		}
 
 		peer.addRole(userRoles.AUTHENTICATED);
-	},*/
-	userMapping           : async ({ peer, userinfo }) =>
+	}
+	// All authenicated users will be AUTHENTICATED,
+	// and those with email ending with @example.com
+	// will also be MODERATOR
+	userMapping : async ({ peer, roomId, userinfo }) =>
+	{
+		if (userinfo.email && userinfo.email.endsWith('@example.com'))
+		{
+			peer.addRole(userRoles.MODERATOR);
+		}
+
+		peer.addRole(userRoles.AUTHENTICATED);
+	},
+	*/
+	userMapping           : async ({ peer, roomId, userinfo }) =>
 	{
 		if (userinfo.picture != null)
 		{
diff --git a/server/lib/Peer.js b/server/lib/Peer.js
index 2b63c87..1affec9 100644
--- a/server/lib/Peer.js
+++ b/server/lib/Peer.js
@@ -1,19 +1,20 @@
 const EventEmitter = require('events').EventEmitter;
 const userRoles = require('../userRoles');
-const config = require('../config/config');
 const Logger = require('./Logger');
 
 const logger = new Logger('Peer');
 
 class Peer extends EventEmitter
 {
-	constructor({ id, socket })
+	constructor({ id, roomId, socket })
 	{
 		logger.info('constructor() [id:"%s", socket:"%s"]', id, socket.id);
 		super();
 
 		this._id = id;
 
+		this._roomId = roomId;
+
 		this._authId = null;
 
 		this._socket = socket;
@@ -87,6 +88,16 @@ class Peer extends EventEmitter
 		this._id = id;
 	}
 
+	get roomId()
+	{
+		return this._roomId;
+	}
+
+	set roomId(roomId)
+	{
+		this._roomId = roomId;
+	}
+
 	get authId()
 	{
 		return this._authId;
diff --git a/server/server.js b/server/server.js
index 43b888b..4d08c09 100755
--- a/server/server.js
+++ b/server/server.js
@@ -279,7 +279,8 @@ async function setupAuth()
 	{
 		passport.authenticate('oidc', {
 			state : base64.encode(JSON.stringify({
-				id : req.query.id
+				peerId : req.query.peerId,
+				roomId : req.query.roomId
 			}))
 		})(req, res, next);
 	});
@@ -324,14 +325,21 @@ async function setupAuth()
 					picture = '/static/media/buddy.403cb9f6.svg';
 			}
 
-			const peer = peers.get(state.id);
+			const peer = peers.get(state.peerId);
+
+			if (peer && peer.roomId !== state.roomId) // The peer is mischievous
+				throw new Error('peer authenticated with wrong room');
 
 			peer && (peer.displayName = displayName);
 			peer && (peer.picture = picture);
 
 			if (peer && typeof config.userMapping === 'function')
 			{
-				await config.userMapping({ peer, userinfo: req.user._userinfo });
+				await config.userMapping({
+					peer,
+					roomId   : state.roomId,
+					userinfo : req.user._userinfo
+				});
 			}
 
 			res.send(loginHelper({
@@ -454,7 +462,7 @@ async function runWebSocketServer()
 		queue.push(async () =>
 		{
 			const room = await getOrCreateRoom({ roomId });
-			const peer = new Peer({ id: peerId, socket });
+			const peer = new Peer({ id: peerId, roomId, socket });
 
 			peers.set(peerId, peer);
 
@@ -480,7 +488,7 @@ async function runWebSocketServer()
 		
 				if (typeof config.userMapping === 'function')
 				{
-					await config.userMapping({ peer, userinfo: _userinfo });
+					await config.userMapping({ peer, roomId, userinfo: _userinfo });
 				}
 			}