Data migration is the process of moving data from one system to another, which may involve changes in storage, database, or application. To perform a successful data migration, it is essential to understand the data structure of the new system, which defines how the data is organized, stored, and accessed. Understanding the new system's data structure will help determine the following aspects of the data migration project:
The scope and requirements of the data migration, such as what data needs to be migrated, how much data needs to be migrated, and what are the quality and performance expectations.
The data mapping and transformation rules, such as how the data elements from the source system correspond to the data elements in the target system, and what transformations or conversions are needed to ensure compatibility and consistency.
The data validation and testing methods, such as how to verify that the migrated data is accurate, complete, and functional in the new system, and how to identify and resolve any errors or issues.
Therefore, understanding the new system's data structure is a crucial first step in a data migration project, as it lays the foundation for the subsequent steps of data extraction, transformation, loading, validation, and testing.

The greatest concern for an IS auditor reviewing contracts for licensed software that executes a critical business process is that software escrow was not negotiated. Software escrow is an arrangement where a third-party holds a copy of the source code and documentation of a licensed software in a secure location. The software escrow agreement specifies the conditions under which the licensee can access the escrowed materials, such as in case of bankruptcy, termination, or breach of contract by the licensor. Software escrow is important for ensuring the continuity and availability of a critical business process that depends on a licensed software. Without software escrow, the licensee may face significant risks and challenges in maintaining, modifying, or recovering the software in case of any disruption or dispute with the licensor. References:
* CISA Review Manual (Digital Version)
* CISA Questions, Answers & Explanations Database

This must be in place before an IS auditor initiates audit follow-up activities, because it indicates that management has acknowledged and accepted the audit findings and recommendations, and has agreed to take corrective actions within a specified timeframe. Audit follow-up activities are the processes and procedures that the IS auditor performs to verify that management has implemented the agreed-upon actions effectively and in a timely manner, and that the audit findings have been resolved or mitigated.
The other options are not required to be in place before an IS auditor initiates audit follow-up activities:
* Available resources for the activities included in the action plan. This is a factor that may affect the feasibility and success of the action plan, but it is not a prerequisite for the audit follow-up activities.
The IS auditor should assess the availability and adequacy of the resources for the action plan during the audit planning and execution phases, and provide recommendations accordingly. However, the IS auditor does not need to wait for the resources to be available before initiating the audit follow-up activities.
* A heat map with the gaps and recommendations displayed in terms of risk. This is a tool that may help the IS auditor prioritize and communicate the gaps and recommendations, but it is not a requirement for the audit follow-up activities. A heat map is a graphical representation of data that uses colors to indicate the level of risk or impact of each gap or recommendation. The IS auditor may use a heat map to support the audit report or presentation, but it does not replace the need for a management response with a committed implementation date.
* Supporting evidence for the gaps and recommendations mentioned in the audit report. This is a component that should be included in the audit report, but it is not a condition for the audit follow-up activities. Supporting evidence is the information or data that supports or substantiates the audit findings and recommendations. The IS auditor should collect and document sufficient, reliable, relevant, and useful evidence during the audit execution phase, and present it in the audit report.
However, the IS auditor does not need to have supporting evidence in place before initiating the audit follow-up activities.