On which part of the IT environment does DevSecOps focus?

DevSecOps is a development practice that integrates security into all phases of the software development lifecycle, from initial design through integration, testing, deployment, and software delivery. DevSecOps focuses on application development, as it aims to deliver secure and robust applications that meet the customers’ needs and expectations. DevSecOps also makes security a shared responsibility of development, security, and operations teams, rather than a separate silo. DevSecOps enables faster and safer software delivery by automating security processes and tools, and addressing security issues as they emerge, rather than at the end of the cycle.

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Implementing and Operating Cisco Security Core Technologies (SCOR) v1.0, Module 6: Securing the Data Center, Lesson 6.2: DevSecOps

What Is DevSecOps? Definition and Best Practices | Microsoft Security

What is DevSecOps? | IBM

What is DevSecOps? | DevSecOps vs. DevOps | VMware