1. Planning.

• Assessment
  Begin by determining who needs access to databases and tables in BigQuery, which resources they need, and the reason for their need. Record the current access rights, assessing if they can be reduced or abolished. Utilize an entitlement detection tool for superior visibility.
• Policy creation
  Establish distinct policies for both granting and revoking access. Include rules about who can request access, under what conditions, and for how long. Especially for higher-level roles, establish time-limited parameters.
• Source of truth
  Sync your JIT access system with an Identity Provider (e.g., Okta, Google Workspace, Azure AD, OneLogin). This serves as the ultimate source for identities. De/escalating individual identities rather than shared accounts allows for improved authorization control and audit accuracy.

2. Execution.

• Self-serve access requests
  Streamline the process by letting users request access through the system, not via people. Increase adoption rates by integrating with IM platforms like Slack or MS Teams. Requests should outline who's asking, the necessary service/resource/role, duration, and reason.

• Approval process
  JIT access allows organizations to delegate approvals to those with business context. Resource owners and business unit managers often understand the context better than IT helpdesks. Use messaging platforms for quick responses, giving approvers all necessary information for an informed decision.

• Conditional approval workflows
  Incorporate your predefined policies into workflows that determine access permissions. Implement them into workflows that dictate who can access what and under which conditions. Assigning if-then conditions is an effective way to handle this.

• Allow for integrations
  Consider integrating JITA with other IT and security systems for more flexibility; Integrate with IT ticketing systems for automated access based on ticket status. Pair with data classification systems to modify policies depending on data sensitivity. Ideally, you should be able to tag resources and bundle them together to streamline this process.
• Automated provisioning and deprovisioning
  Develop a comprehensive understanding of BigQuery to effectively grant and revoke finely-tuned access automatically. This is critical for JIT Access as it reduces the dependence on waiting for people to make time. Automating the deprovisioning of access is pivotal to JIT access and the principle of least privilege access (POLP).
• Access methods
  For BigQuery JIT Access, APIs are preferable due to their flexibility and real-time capabilities. Yet, a blend might be necessary.

3. Maintenance.

• Regular audits
  Occasionally examine access logs to ensure JIT access is functioning as expected. Look for any unusual patterns or behaviors either directly or by feeding the logs into your SIEM.
• User training
  Inform users, particularly privileged users, about the importance of least privilege, JIT Access, and BigQuery's operations. Make sure users know how to request access when required.
• Feedback loop
  Ensure a consistent review of your JIT access procedures. Solicit feedback from users and IT staff to understand where improvements can be made.

By adopting this structured approach, you'll be able to efficiently implement a robust Just-in-Time Access system for BigQuery.