The reliable message transmission system client package also consists of MQTT_Class and RMS_Client_Class in Fig. 9. And the main class method of RMS_Client_Class Table 5. getRMSTopicMessage() method generates new message with a sequence number. getOriginalMessage() method get the original message from the message which is combined with a sequence number. getRequestMissedMessage() method requests a missed message if there is a missed message after comparing the sequence number with previous sequence number. The client module has to store previous message sequence number right before current message sequence number.