Rest API和Web Socket API之间的区别

在物联网中，有2个通信API –

• 基于REST的通信API
• 基于Web套接字的通信API

可以使用REST原理或使用Web套接字协议来实现Web服务–

1.基于REST的通信API：
代表性状态转移(REST)是一组体系结构原则，通过这些原则，您可以设计着重于系统资源以及如何寻址和转移资源状态的Web服务和Web API。 REST API遵循请求-响应通信模型。 REST体系结构约束适用于分布式超媒体系统中的组件，连接器和数据元素。

2.基于Web套接字的通信API：
Web套接字API允许客户端和服务器之间的双向全双工通信。它遵循排他对通信模型。此通信API不需要为要在客户端和服务器之间发送的每条消息建立新的连接。一旦建立了连接，就可以连续不断地发送和接收消息，而不会发生任何中断。 WebSocket API适用于具有低延迟或高吞吐量要求的IoT应用程序。

Rest API和Web Socket API之间的区别：

S.NO.	REST API	WEB SOCKET API
1.	It is Stateless protocol. It will not store the data.	It is Stateful protocol. It will store the data.
2.	It is Uni-directional. Only eiether server or client will communicate.	It is Bi-directional. Messages can be received or sent by both server or client.
3.	It is Request-response model.	It is Full duplex model.
4.	HTTP request contains headers like head section, title section.	It is suitable for real time applications. It does not have any overhead.
5.	New TCP connection will be set up for each HTTP request.	Only Single TCP connection.
6.	Both horizontal and vertical scaling (we can add many resources and number of users both horizontally and vertically).	Only vertical scaling (we can add resources only vertically).
7.	It depends upon the IP address and port number to retrive the data.	It depends upon the HTTP methods to retrive the data.
8.	It is slower than web socket regarding the transmission of messages.	web socket transmits messages very fastly than REST API.
9.	It does not need memory or buffers to store the data.	It require memory and buffers to store the data.