Life-extension is the work needed to keep an existing plant safely operating beyond its original design life. It usually combines hardware upgrades, component replacement, detailed inspections, and formal regulatory review to prove that the facility still meets safety requirements.
In cyber security, life-extension matters because older industrial sites often rely on legacy control systems, proprietary protocols, and long-lived equipment that cannot be replaced quickly. Extending service life can reduce the need for a full rebuild, but it also increases exposure to outdated software, weak segmentation, and hard-to-patch assets. Defenders use asset inventories, secure maintenance access, network monitoring, and planned modernization to reduce risk while the plant remains in service.