diff --git a/src/knx/secure_application_layer.cpp b/src/knx/secure_application_layer.cpp
index 6dde69a..bddf56f 100644
--- a/src/knx/secure_application_layer.cpp
+++ b/src/knx/secure_application_layer.cpp
@@ -73,6 +73,24 @@ void SecureApplicationLayer::dataBroadcastConfirm(AckType ack, HopCountType hopT
     ApplicationLayer::dataBroadcastConfirm(ack, hopType, priority, apdu, status);
 }
 
+void SecureApplicationLayer::dataSystemBroadcastIndication(HopCountType hopType, Priority priority, uint16_t source, APDU& apdu)
+{
+    if (apdu.type() == SecureService)
+    {
+        // Secure APDU is not allowed in SystemBroadcast
+        println("Secure APDU in SystemBroadcast not allowed!");
+    }
+    else
+    {
+        ApplicationLayer::dataSystemBroadcastIndication(hopType, priority, source, apdu);
+    }
+}
+
+void SecureApplicationLayer::dataSystemBroadcastConfirm(HopCountType hopType, Priority priority, APDU& apdu, bool status)
+{
+    ApplicationLayer::dataSystemBroadcastConfirm(hopType, priority, apdu, status);
+}
+
 void SecureApplicationLayer::dataIndividualIndication(HopCountType hopType, Priority priority, uint16_t tsap, APDU& apdu)
 {
     if (apdu.type() == SecureService)
diff --git a/src/knx/secure_application_layer.h b/src/knx/secure_application_layer.h
index 94805c4..a99add1 100644
--- a/src/knx/secure_application_layer.h
+++ b/src/knx/secure_application_layer.h
@@ -30,6 +30,8 @@ class SecureApplicationLayer :  public ApplicationLayer
                                   APDU& apdu, bool status) override;
     virtual void dataBroadcastIndication(HopCountType hopType, Priority priority, uint16_t source, APDU& apdu) override;
     virtual void dataBroadcastConfirm(AckType ack, HopCountType hopType, Priority priority, APDU& apdu, bool status) override;
+    virtual void dataSystemBroadcastIndication(HopCountType hopType, Priority priority, uint16_t source, APDU& apdu) override;
+    virtual void dataSystemBroadcastConfirm(HopCountType hopType, Priority priority, APDU& apdu, bool status) override;
     virtual void dataIndividualIndication(HopCountType hopType, Priority priority, uint16_t source, APDU& apdu) override;
     virtual void dataIndividualConfirm(AckType ack, HopCountType hopType, Priority priority, uint16_t tsap, APDU& apdu, bool status) override;
     virtual void connectIndication(uint16_t tsap) override;