diff --git a/ws/ws-tests.ts b/ws/ws-tests.ts
index ec2bc431e0..a8afa8cb99 100644
--- a/ws/ws-tests.ts
+++ b/ws/ws-tests.ts
@@ -1,6 +1,8 @@
 /// <reference path="ws.d.ts" />
 
-import WebSocket = require('ws');
+import * as WebSocket from 'ws';
+import * as http from'http';
+
 var WebSocketServer = WebSocket.Server;
 
 {
@@ -29,7 +31,7 @@ var WebSocketServer = WebSocket.Server;
 {
     var wss = new WebSocketServer({port: 8080});
 
-    function broadcast(data: any) {
+    const broadcast = function(data: any) {
         for(var i in wss.clients)
             wss.clients[i].send(data);
     };
@@ -51,3 +53,24 @@ var WebSocketServer = WebSocket.Server;
         }, 500);
     });
 }
+
+{
+    const verifyClient = function(
+      info: {
+        origin: string
+        secure: boolean
+        req: http.ServerRequest
+      }
+      , callback: (res: boolean) => void
+    ): void {
+        callback(true)
+    }
+    
+    var wsv = new WebSocketServer({
+        verifyClient
+    })
+    
+    wsv.on('connection', function connection(ws) {
+        console.log(ws.protocol)
+    })
+}
\ No newline at end of file
diff --git a/ws/ws.d.ts b/ws/ws.d.ts
index d9a1338d21..6b94bee19d 100644
--- a/ws/ws.d.ts
+++ b/ws/ws.d.ts
@@ -22,6 +22,7 @@ declare module "ws" {
         url: string;
         supports: any;
         upgradeReq: http.ServerRequest;
+        protocol: string;
 
         CONNECTING: number;
         OPEN: number;
@@ -87,15 +88,16 @@ declare module "ws" {
     }
 
     namespace WebSocket {
+                
+        type VerifyClientCallbackSync = (info: {origin: string; secure: boolean; req: http.ServerRequest}) => boolean;
+        type VerifyClientCallbackAsync = (info: {origin: string; secure: boolean; req: http.ServerRequest}
+                                            , callback: (res: boolean) => void) => void;
+
         export interface IServerOptions {
             host?: string;
             port?: number;
             server?: http.Server;
-            verifyClient?: {
-                (info: {origin: string; secure: boolean; req: http.ServerRequest}): boolean;
-                (info: {origin: string; secure: boolean; req: http.ServerRequest},
-                                                 callback: (res: boolean) => void): void;
-            };
+            verifyClient?: VerifyClientCallbackAsync | VerifyClientCallbackSync;
             handleProtocols?: any;
             path?: string;
             noServer?: boolean;