CI Fortify – Advice for isolating vital systems CI Fortify – Advice for isolating vital systems (PDF) CISA and the Australian Signals Directorate’s Australian Cyber Security Centre (ASD’s ACSC), in collaboration with the Federal Bureau of Investigation and international partners, released joint guidance CI Fortify – Advice for isolating vital systems . This guidance contains practical steps for critical infrastructure (CI) organizations to isolate vital operational technology and enabling systems from all other networks in the event of disruption or crisis and operate in isolation for an exten