phase is the Operational Impact Analysis. This step is accomplished through the development of operational dependency matrices and the application of operations research methods. Potential operational impacts and service-level requirements are then reflected in the asset's criticality attributes and criticality index in the CIP program. IV. The fourth step is the Vulnerability Assessment. This step is accomplished through multiple channels. Through the CIP program, all critical assets have a baseline vulnerability index, which is calculated from inputs associated with the class of asset and geographic region such as the probability of natural disasters, criminal or national security events, and technological failures. Asset owners, host installations, the sector CIAO, or other DoD entities may provide asset operational readiness and emergency preparedness information. V. The fifth and final step in the Analysis and Assessment phase is Interdependency Analysis. Interdependency analysis seeks to map functions and relationships among DI sectors. As a result of the Interdependency Analysis, the criticality attributes for previously identified assets may be updated and additional critical assets may be identified to the CIP program. Multiple groups within the DoD CIP structure perform analysis and assessment activities. Translating the analysis and assessment process into concrete data requires specific activities, tasks, and tools. Phase 1 Example in the “Real World” On August 24, 2001, the Director of the Joint Staff requested USPACOM to serve as the lead support Combatant Command for creating a CIP first-ever theater CIP Plan – known as the “CIP Appendix 16 Plan”. The following is how USPACOM approached the task. USPACOM focused the Analysis and Assessment phase by organizing its activities to answer three major questions: What is critical? Is it vulnerable? What can be done? To answer the question, “What is critical?”, USPACOM outlined a three-step procedure: First, identify the project focus. Second, complete an operational analysis. Third, complete a Defense Infrastructure analysis. To accomplish these steps, USPACOM adopted a methodology that focuses its CIP efforts on Tier 1 assets. Tier 1 assets are assets that could cause mission failure if they are compromised or damaged. The methodology UAPACOM adopted and modified is Mission Area Analysis, or MAA. The MAA links combatant command missions to infrastructure assets that are critical to a given Operations Plan, or OPLAN, Contingency Plan, or CONPLAN, or Crisis Action Plan. Typically, the MAA process determines the assessment site priorities. USPACOM modified the process and selected the CIP assessment sites and installations