Transforming SIEM Economics and Visibility with Microsoft Sentinel
Microsoft Technology: Microsoft Sentinel, Microsoft Defender XDR, Microsoft Sentinel Data Lake
Ascent Solution: Sentinel Rapid Adoption + SIEM Migration
Ascent partnered with Tetra Tech to dramatically reduce SIEM costs while improving security visibility through a strategic migration from Splunk to Microsoft Sentinel. The engagement delivered significant cost savings, enhanced detection capabilities, and a modern, scalable SIEM architecture.
Results at a Glance:
The Challenge
Ballooning SIEM Costs and Limited Visibility
Tetra Tech is a large, globally distributed organization responsible for managing massive volumes of telemetry and network traffic across thousands of endpoints and edge locations. Their legacy SIEM environment, built on Splunk, ingested over 6 TB of logs per day, driven heavily by noisy firewall data and manual ingestion pipelines.
This created several critical challenges: escalating SIEM licensing and storage costs, inefficient ingestion pipelines especially for Fortinet traffic, difficulty scaling visibility without skyrocketing spend, and underutilization of Microsoft E5 Security entitlements.
Maintaining the Splunk environment became financially unsustainable, even as visibility gaps persisted. Tetra Tech needed a modern SIEM approach—one designed for scale, automation, and cost efficiency.
The Solution
Migrating to Sentinel + Data Lake for Exponential Savings
Tetra Tech partnered with Ascent Solutions to lead a strategic migration from Splunk to Microsoft Sentinel, leveraging Sentinel's new Data Lake–centric architecture to completely rethink SIEM cost, retention, and insight. Ascent delivered a modern SIEM ingestion strategy built for scale.
Key Focus Areas
- Shifted high-volume syslog and firewall traffic into Sentinel Data Lake, drastically reducing ingestion cost.
- Re-architected ingestion pipelines to eliminate manual log configuration.
- Reduced daily ingestion from 6 TB to 2.5 TB through intelligent data tiering.
- Optimized Microsoft E5 ingestion benefits (5 MB/user/day) to unlock additional cost savings.
- Designed a repeatable, scalable ingestion architecture for long-term SOC modernization.
The Impact
More Visibility, Lower Cost, Stronger Security Posture
The migration to Microsoft Sentinel delivered measurable improvements immediately. By redesigning Tetra Tech's ingestion architecture and shifting high-volume firewall logs into Sentinel's Data Lake, Ascent helped the organization unlock a level of cost efficiency, performance, and visibility that was not possible in their Splunk environment.
Key Outcomes
- Major Cost Reduction: By moving to Sentinel's Data Lake model, Tetra Tech significantly reduced ingestion cost while increasing retention flexibility and analytical depth.
- Improved Detection and Visibility: With Sentinel and Defender XDR working together, Tetra Tech now detects more alerts and more potential threats than before, without adding more tooling.
- Smarter Use of Existing Investments: As an E5-licensed organization, Tetra Tech finally realized the financial and operational benefits of leveraging the Microsoft Security stack they were already paying for.
- Scalable SIEM Architecture: The migration created a foundation that is easier to maintain, easier to extend, and ready for evolving security and data requirements.
- Repeatable Pattern for SIEM Displacement: This success demonstrates that enterprises can move away from high-cost SIEMs like Splunk without losing visibility or maturity—in fact, Tetra Tech gained both.
Tetra Tech's leadership highlights Sentinel's ability to expand visibility, eliminate unnecessary tooling, and dramatically reduce SIEM spend, all while improving operational efficiency.
The Future
Continued SOC Modernization
Ascent continues to support Tetra Tech's security journey, providing guidance on additional data sources, analytics optimization, automation opportunities, and future SOC modernization efforts.
Our goal is to turn security modernization into a catalyst for operational efficiency and long-term risk reduction, building a sustainable, high-performing security operations foundation that evolves with your organization.
Why Choose Ascent
Tetra Tech partnered with Ascent because of our proven ability to execute large-scale Microsoft Sentinel migrations with speed, precision, and measurable business impact. As a Microsoft-focused security consultancy, Ascent brings deep technical expertise, extensive field experience, and a repeatable framework for transforming SIEM operations.
By combining technical execution with strategic planning, Ascent helped Tetra Tech transform their security operations while dramatically reducing costs.
Ready to modernize your SIEM? Explore Ascent's Sentinel Rapid Adoption Offer and see how we can help reduce SIEM cost, improve detection, and unlock the full power of Microsoft Security.
