Chief information security officers as compared to chief security officers are seeing more complex threats and solutions relative to data center and network operations.

Information technology rates data centers by tiers. Tier 1 to 4 is a standardized methodology used to define uptime of a data center. This is useful for measuring:

• Data center performance
• Investment
• ROI (return on investment)

Tier 4 data centers are considered the most robust and least prone to failures. Tier 4 is designed to host mission-critical servers and computer systems, with fully redundant subsystems (cooling, power, network links, storage) and compartmentalized security zones controlled by biometric access control methods. Naturally, the simplest is a Tier 1 data center used by small businesses or shops.

• Tier 1 = Non-redundant capacity components (single uplink and servers).
• Tier 2 = Tier 1 + Redundant capacity components.
• Tier 3 = Tier 1 + Tier 2 + Dual-powered equipment and multiple uplinks.
• Tier 4 = Tier 1 + Tier 2 + Tier 3 + All components are fully fault-tolerant including uplinks, storage, chillers, HVAC systems, servers, etc. Everything is dual-powered.