diff --git a/websocket-sharp/Net/ServerSslConfiguration.cs b/websocket-sharp/Net/ServerSslConfiguration.cs
index 9920b8c0..c10b4dc1 100644
--- a/websocket-sharp/Net/ServerSslConfiguration.cs
+++ b/websocket-sharp/Net/ServerSslConfiguration.cs
@@ -58,6 +58,14 @@ namespace WebSocketSharp.Net
 
     #region Public Constructors
 
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ServerSslConfiguration"/> class.
+    /// </summary>
+    public ServerSslConfiguration ()
+    {
+      _enabledSslProtocols = SslProtocols.Default;
+    }
+
     /// <summary>
     /// Initializes a new instance of the <see cref="ServerSslConfiguration"/> class
     /// with the specified <paramref name="serverCertificate"/>.