Which concept best represents the idea of reducing downtime during system updates?

The concept that best represents the idea of reducing downtime during system updates is blue-green deployment. This deployment strategy involves maintaining two identical environments, referred to as "blue" and "green." At any point in time, one of these environments is live and serving user traffic, while the other is staged with the updated application or system.

When a new version of the application is ready to be deployed, it is uploaded to the idle environment (for example, if blue is live, the update is applied to green). After the update is complete and validated, traffic can be switched from the live environment to the updated one almost instantaneously. This transition is typically seamless to users, thus minimizing downtime and reducing the risk of disruption during the update process.

In contrast, continuous integration focuses on frequent integration of code changes, but does not specifically address reducing downtime during deployment. The waterfall methodology follows a linear approach to project management, which does not allow for rapid updates and can lead to longer downtimes. Agile sprints involve iterative progress and development, but like continuous integration, they do not inherently tackle the challenge of deploying updates with minimal downtime.

Ultimately, blue-green deployment is designed specifically to ensure that system updates are applied with high availability and minimal interruption to users