PROFIsafe is a standard for safe communication in industrial automation networks. It allows for both standard and failsafe communication over the same network using PROFIBUS or PROFINET. PROFIsafe ensures safety by adding features like consecutive numbering of data packets, time monitoring, and authenticity monitoring using unique addresses. It detects possible faults like delays, data loss, or address errors. PROFIsafe supports coexistence of standard and safety-related programs on one CPU without impacting each other. It uses techniques like time and data redundancy to achieve safety without full redundancy. Network security for industrial automation is also important, and can be implemented through measures like secure network segmentation, firewalls, VPNs, and ongoing network monitoring.