Network Segmentation

Forescout’s March 23, 2026 segmentation release matters because it moves network security discussions away from static IP ranges and toward identity, behavior, and risk across mixed environments. For CCIE Security engineers, the real story is not the press release headline, it is that vendor-agnostic segmentation is becoming a practical answer to zero-trust enforcement in networks that include Cisco, Arista, OT controllers, medical gear, unmanaged IoT, and assets that will never run an agent. ...

Cisco ISE combined with TrustSec is the most widely deployed zero trust network segmentation solution in enterprise environments today. It uses Scalable Group Tags (SGTs) to enforce identity-based access policies across switches, routers, and firewalls — replacing thousands of IP-based ACLs with a centralized policy matrix that follows users and devices wherever they connect. Key Takeaway: TrustSec SGT-based segmentation is the practical implementation of zero trust that enterprises are actually deploying in 2026, and mastering it is essential for both production network engineers and CCIE Security candidates. ...