# What are shadow perimeters in industrial environments?

- Link: https://www.agilicus.com/faq/what-are-shadow-perimeters-in-industrial-environments/
- Published: 2026-05-11T15:51:26+00:00
- Author: Don Bowman

Shadow perimeters refer to undocumented or unauthorised connections that bypass 
established security boundaries, such as rogue cellular modems or vendor-installed
wireless access points. These connections create invisible entry points into the
operational technology network, circumventing firewalls and monitoring tools. To
maintain a secure posture, organisations must perform physical and logical audits
to identify and secure these hidden entry points. Learn more about [securing boundaries in our strategic blueprint](https://www.agilicus.com/white-papers/industrial-cyber-security-best-practices/).

For more information, see [Industrial Cyber Security Best Practices](https://www.agilicus.com/white-papers/industrial-cyber-security-best-practices/).