Common protocols for the internet of Things

Protocol	CoAP	XMPP	RESTful HTTP	MQTT
Transport	UDP	tcp	tcp	tcp
messagin G	request/response	publish/subscribe request/response	request/response	Publish /subscribe request/response
2G, 3G, 4G suitability (1000s nodes)	excellent	E Xcellent	Excellent	excellent
lln suitability (1000s nodes)	Excell ENT	Fair	Fair	Fair
Compute Resources	10Ks ram/flash	10Ks ram/flash	10Ks ram/flash	10Ks ram/flash
Success storied	Utility Field Area Networks	Remote Management of consumer white goods	Smart Energy Profiles 2 (Premise Energy management/home Services)	extending enterprise Messaging into IoT applications

Xmpp

XMPP is a subset of XML based on standard Common Markup Language protocol, which inherits the flexible development in XML environment. As a result, XMPP-based applications have super-scalable capability. The extended XMPP can handle the user's needs by sending extended information, as well as creating applications such as content publishing systems and address-based services at the top of XMPP. Furthermore, XMPP contains a software protocol for the server side that enables it to talk to another, making it easier for developers to build customer applications or add functionality to a well-equipped system.

Mqtt

The MQTT (message Queuing Telemetry Transport, Messaging queue telemetry transmission) is an Instant Messaging protocol developed by IBM that is likely to be an important part of the Internet of things. The protocol supports all platforms, almost all connected items and external connections, and is used as a communication protocol for sensors and actuators (such as the Internet of homes via Twitter).

CoAP

Coap is synonymous with the Restricted application protocol (Constrained application Protocol). In recent years, experts have predicted that more devices will be connected to each other, and that the number of these devices would be far greater than the number of humans. In this context, the Internet of things and technology have emerged. Although it is easy for people to connect to the Internet, access to the Internet is difficult for those tiny devices. In the current world of PC, information exchange is implemented via TCP and Application layer protocol HTTP. But for small devices, implementing the TCP and HTTP protocols is clearly an excessive requirement. The COAP protocol is designed to allow small devices to connect to the Internet. Coap is an application-layer protocol that runs on top of the UDP protocol instead of running on TCP like HTTP. The COAP protocol is very small and the smallest packet is only 4 bytes.

RESTful HTTP

REST refers to a set of schema constraints and principles. Applications or designs that meet these constraints and principles are RESTful.

The most important REST principle of a WEB application is that the interaction between the client and the server is stateless between requests. Each request from the client to the server must contain the information necessary to understand the request. If the server restarts at any point in time between requests, the client will not be notified. In addition, stateless requests can be answered by any available server, which is ideal for environments such as cloud computing. Clients can cache data to improve performance.

Other

The MQTT protocol is an IBM master-push protocol that, in the present case, has the advantage over XMPP and restful. If we do a PK on the above results, I think the final result is Mqtt vs CoAP. HTTP is too heavy and inflexible for embedded devices, not to mention XMPP, and there is a coap--agreement in the draft phase for MQTT.

Note:

In foreign countries, home appliances are usually divided into 4 categories: white goods, black appliances, beige appliances and emerging green appliances.

White goods refers to the products that can replace people to do housework, including washing machines, refrigerators, or for people to provide a higher quality of life environment products, such as air-conditioning, electric heater;

Black home appliances are products that can provide entertainment, such as: DVD player, color TV, audio, game consoles, cameras, cameras, video game consoles, home theater, telephone, telephone answering machine;

Beige household appliances refers to computer information products, green appliances, refers to the quality of qualified under the premise, can be efficient use and energy-saving products;

Green appliances in the use of the human body and the surrounding environment is not harmful, after the scrap can also be recycled home appliance products.

　　

There is no doubt that for the internet of things, the main object of our revolution is consumer-grade white goods (consumer goods)

Reference: https://www.phodal.com/blog/iot-protocols-coap-mqtt-xmpp-restful-http/

Common protocols for the internet of Things