void createMeshMessage(@NonNull final Message message) { //Access message
        if (message instanceof AccessMessage) {
            super.createMeshMessage(message);
            final AccessMessage accessMessage = (AccessMessage) message;
            final byte[] encryptedTransportPDU = encryptUpperTransportPDU(accessMessage);
            MeshLogger.verbose(TAG, "Encrypted upper transport pdu: " + MeshParserUtils.bytesToHex(encryptedTransportPDU, false));
            accessMessage.setUpperTransportPdu(encryptedTransportPDU);
        } else {
            createUpperTransportPDU(message);
        }
    }
Creates a mesh message containing an upper transport access pdu

@param message The access message required to create the encrypted upper transport pdu
mesh/src/main/java/no/nordicsemi/android/mesh/transport/UpperTransportLayer.java