Layers of a Real-Time System

A real-time application consists of:

• Clients
• Real-time communication layer
• Back-end servers

These three work together to achieve business objectives. Each layer’s cooperation and proper function are essential in developing a successful application. For example, a bug in the client could prevent proper connection to the server and reduce its ability to operate instantly. A defect in the server could delay or prevent messages from being sent to a connected client. Before we look at the layers of a real-time system, let’s define real-time.

Levels of a real-time system

There are different levels of guarantee in a real-time system.

• Hard real-time
• Soft real-time

Hard real-time

Hardware systems that have strict time guarantees are considered hard real-time.

Example

An airplane’s control system needs to always respond within strict time limits.

Soft real-time

Soft real-time applications can have several seconds of delay when updating the user’s view, thus minimizing the amount of time the update takes.

A soft real-time application should update to the correct state without user intervention. This course will look at soft real-time applications. Soft real-time is ...