Modernising security operations with a cloud-native SIEM platform

The Challenge

The organisation had a mature internal IT and security capability and was self-managing a number of third-party security tools, including a legacy SIEM and endpoint security platforms. However, onboarding new applications, workloads, and data sources into the existing security stack had become increasingly complex and resource intensive.

While the organisation was initially unconvinced of the value of migrating to a cloud-native SIEM, it recognised the need to explore alternative approaches that could simplify operations, reduce overhead, and improve threat visibility across a growing hybrid and cloud environment.

Key Challenges

• Operational complexity: Managing and maintaining multiple legacy security platforms
• Scalability: Difficulty onboarding new applications and workloads efficiently
• Resource pressure: High operational overhead for internal security teams
• Visibility: Limited ability to correlate threats across cloud and endpoint environments
• Change assurance: Need to validate value before committing to a new SIEM platform

The Solution

CWSI invited the organisation to participate in the Microsoft Cyber Security Investment (CSI) programme and delivered a Modern SecOps engagement to demonstrate the value of Microsoft Sentinel.

The engagement showcased Sentinel’s cloud-native architecture, simplified onboarding, and ability to integrate seamlessly with existing Microsoft security tools. A controlled production rollout for a defined data set provided clear, measurable benefits when compared to the existing SIEM platform, helping build confidence across regional IT teams.

Key elements of the solution included:

• Modern SecOps engagement delivered through the CSI programme
• Proof-of-value deployment of Microsoft Sentinel for targeted workloads
• Simplified onboarding aligned to defined threat vectors
• Strategic guidance for SIEM migration and platform consolidation
• Roadmap development for broader Microsoft security adoption

The Result

The engagement resulted in a successful migration to Microsoft Sentinel and a clear roadmap to modernise security operations across the organisation’s global estate.

Key Outcomes

• Successful replacement of the legacy SIEM platform with Microsoft Sentinel
• Reduced operational overhead through cloud-native security operations
• Improved threat detection and visibility across cloud and endpoint environments
• Approved uplift of 4,000 users globally to Microsoft 365 E5
• ECIF funding secured to deploy Microsoft Defender for Endpoint and Microsoft Cloud Apps
• Fully integrated security architecture spanning Sentinel, Defender, and Intune

Why CWSI

CWSI worked closely with both regional and global IT teams to deliver a structured, evidence-based approach to security modernisation. By demonstrating real-world value through a production deployment, CWSI helped the organisation confidently transition from legacy tooling to a modern, integrated Microsoft security platform that supports long-term scalability and resilience.

“CWSI’s depth of knowledge, experience and support have been critical in our implementation of several Microsoft solutions such as Sentinel, Defender for Endpoint and Cloud Apps, and our recent move to E5.”

Cyber Services Manager, Global Financial Services Organisation