diff --git a/lib/options.json b/lib/options.json
index c09c696fe8..217ee5a631 100644
--- a/lib/options.json
+++ b/lib/options.json
@@ -369,7 +369,8 @@
                 }
               ]
             }
-          }
+          },
+          "additionalProperties": false
         },
         {
           "enum": ["sockjs", "ws"]
diff --git a/test/options.test.js b/test/options.test.js
index 48e0f89752..409dc07bec 100644
--- a/test/options.test.js
+++ b/test/options.test.js
@@ -403,36 +403,54 @@ describe('options', () => {
           'ws',
           'sockjs',
           {
-            server: 'sockjs',
+            transportMode: {
+              server: 'sockjs',
+            },
           },
           {
-            server: require.resolve('../lib/servers/SockJSServer'),
+            transportMode: {
+              server: require.resolve('../lib/servers/SockJSServer'),
+            },
           },
           {
-            server: SockJSServer,
+            transportMode: {
+              server: SockJSServer,
+            },
           },
           {
-            client: 'sockjs',
+            transportMode: {
+              client: 'sockjs',
+            },
           },
           {
-            client: require.resolve('../client/clients/SockJSClient'),
+            transportMode: {
+              client: require.resolve('../client/clients/SockJSClient'),
+            },
           },
           {
-            server: SockJSServer,
-            client: require.resolve('../client/clients/SockJSClient'),
+            transportMode: {
+              server: SockJSServer,
+              client: require.resolve('../client/clients/SockJSClient'),
+            },
           },
         ],
         failure: [
           'nonexistent-implementation',
           null,
           {
-            notAnOption: true,
+            transportMode: {
+              notAnOption: true,
+            },
           },
           {
-            server: false,
+            transportMode: {
+              server: false,
+            },
           },
           {
-            client: () => {},
+            transportMode: {
+              client: () => {},
+            },
           },
         ],
       },