Aiming to the disadvantage that memory consumption rises with the increase of message subscribers in transmission mode of Mosquitto, it designs and realizes a new kind of transmission mode which is more suitable in large file transfer and decreases the memory consumption. The experimental results show that, when there are 100 message subscribers and the length of message is 25 MB, compared with the transmission mode of Mosquitto, the memory consumption of new mode is 6% of the former. It proves that the new...