Case Study: Fortune 300 SaaS Company achieves secure, scalable segmentation and avoids network re-architecture with Illumio

SaaS Giant Secures High-Value Assets at Scale With Illumio

A Fortune 300 web-scale SaaS pioneer faced a potential crisis when its decade-old, network-embedded security model ran into ruleset explosion—switches hit TCAM limits and the team risked being unable to provision new servers for six months—while fragmented automation and board-level scrutiny made a full network re-architecture (>$50M) impossible. The organization needed a way to secure 50,000 workloads across five data centers without disrupting business or delaying a massive migration.

By deploying Illumio Core’s host-based segmentation and real-time application dependency map, teams modeled and tested policies safely, applied consistent security that followed workloads, and avoided touching the network. The effort came in under budget, enabled the company to scale to 70,000 workloads across five data centers, eliminated firewall sprawl, and cleaned up automation so DevOps could deliver faster and more reliably.