Server-Sent Events

Server-Sent Events (SSE) is a standard way to send data streams from a server to clients. In this next section, we will learn how to implement it using the Spring Framework.

Also, we will understand the main differences between SSE and WebSockets.

A few words about the HTTP protocol

HTTP is an application layer protocol in the OSI model. The application layer is the last layer represented in the OSI model. It means this layer is closer to the user interface. The main purpose of this layer is to send and receive the data input by the user. In general, it happens by the user interface, also known as applications, such as file transfer and sending an email.

There are several protocols on the application layer such as Domain Name Service (DNS), which translates the domain names to IP address, or SMTP, whose main purpose is to deliver an email to a mail manager application.

The application layer interacts directly with software such as email clients, for instance; there are no interactions...