From b779d0463698edf7231af190b29b598a41d8da12 Mon Sep 17 00:00:00 2001
From: patagona <info@patagona.dev>
Date: Sat, 23 Oct 2021 10:31:44 +0200
Subject: [PATCH] let the OS choose the supported TLS ptotocols when connecting
 to a MQTT broker (#1271)

---
 .../Options/MqttClientOptionsBuilderTlsParameters.cs      | 6 +-----
 Source/MQTTnet/Client/Options/MqttClientTlsOptions.cs     | 8 ++------
 2 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/Source/MQTTnet/Client/Options/MqttClientOptionsBuilderTlsParameters.cs b/Source/MQTTnet/Client/Options/MqttClientOptionsBuilderTlsParameters.cs
index 9726fe0..27ad435 100644
--- a/Source/MQTTnet/Client/Options/MqttClientOptionsBuilderTlsParameters.cs
+++ b/Source/MQTTnet/Client/Options/MqttClientOptionsBuilderTlsParameters.cs
@@ -19,11 +19,7 @@ namespace MQTTnet.Client.Options
 
         public Func<MqttClientCertificateValidationCallbackContext, bool> CertificateValidationHandler { get; set; }
 
-#if NETCOREAPP3_1 || NET5_0
-        public SslProtocols SslProtocol { get; set; } = SslProtocols.Tls13;
-#else
-        public SslProtocols SslProtocol { get; set; } = SslProtocols.Tls12;
-#endif
+        public SslProtocols SslProtocol { get; set; } = SslProtocols.None;
 
 #if WINDOWS_UWP
         public IEnumerable<IEnumerable<byte>> Certificates { get; set; }
diff --git a/Source/MQTTnet/Client/Options/MqttClientTlsOptions.cs b/Source/MQTTnet/Client/Options/MqttClientTlsOptions.cs
index 138fabc..e2d57ee 100644
--- a/Source/MQTTnet/Client/Options/MqttClientTlsOptions.cs
+++ b/Source/MQTTnet/Client/Options/MqttClientTlsOptions.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Net.Security;
 using System.Security.Authentication;
@@ -26,11 +26,7 @@ namespace MQTTnet.Client.Options
         public List<SslApplicationProtocol> ApplicationProtocols { get; set; }
 #endif
 
-#if NETCOREAPP3_1 || NET5_0
-        public SslProtocols SslProtocol { get; set; } = SslProtocols.Tls13;
-#else
-        public SslProtocols SslProtocol { get; set; } = SslProtocols.Tls12;
-#endif
+        public SslProtocols SslProtocol { get; set; } = SslProtocols.None;
 
         [Obsolete("This property will be removed soon. Use CertificateValidationHandler instead.")]
         public Func<X509Certificate, X509Chain, SslPolicyErrors, IMqttClientOptions, bool> CertificateValidationCallback { get; set; }