Advantages of MQTT compared to TCP long connections

Advantages of MQTT compared to TCP long connections:

1. The agreement is more standardized

MQTT is a standard RFC protocol, which is more standard than private protocols. The benefits are:

(1) The protocol is very complete and can be used for production immediately. After each end implements the same set of protocols, they can communicate; private protocols also require a lot of verification to see if there are any flaws or lack of consideration.

(2) The standardization of the protocol brings a large number of open source components and reduces the difficulty of development. As the 5G ecosystem of the Internet of Things gets better and better, there are more and more open source components, which can reduce the amount of repeated coding.

(3) Standard protocols facilitate third-party access. When third-party devices and platforms want to connect, take out a set of standard MQTT protocols and slap them in the face, and no one will have any reason to ask for interface changes.

2. The MQTT protocol has developed many functions that are beneficial to the Internet of Things.

Of course, TCP can also do it by developing its own protocol, but MQTT has already completed its functions, so developing the protocol by yourself will make it more difficult. Advantageous features include:

(1) Heartbeat mechanism. There is no need to do the heartbeat of the business protocol layer yourself.

(2) Will information. This is useful for IoT devices that often go offline.

(3) QoS quality level offline message. Messages in persistent sessions that are offline can also be received, which is useful for IoT scenarios where the network is unstable but must be delivered.

(4) Asynchronous mechanism. After MQTT sends the message with QoS1/2, the device does not need to take care of it anymore, and the cloud is responsible for failure retransmission.

(5) Subscription publishing mechanism. Publish once and subscribe to multiple clients, which saves power and traffic in M2M scenarios.

(6) Theme and security. You can use themes to easily control client permissions.

3. Understand data content and use data to generate value

The current mainstream design of IoT has two parts:

(1) Equipment shadow value

The device shadow contains the status of the device. Instead of querying the devices one by one through transparent transmission, you can directly access the device shadow in the cloud to get the status data of all current devices. This contains huge benefits. For example, statistical data can be used to guide the development of new products and functions. , statistics are used to fix bugs, etc.

(2) Value of rule engine

AWS, Alibaba Cloud, Tencent Cloud, and Baidu Cloud are all called rule engines. Since MQTT subdivides specific topics, when the business is differentiated by topic, the data of the corresponding topic will be automatically distributed to other data recipients directly through the rules configured by the rule engine. These are TCP transparent transmission and the cloud does not understand the business. Data content cannot do this.

Summarize

Although MQTT has certain advantages in many aspects, choosing MQTT or TCP long connection transparent transmission still depends on the specific business scenario. Choosing the most appropriate one is the most important.