Each of the following are dependencies that must be considered when reviewing the BIA after cloud migration except:

A Business Impact Analysis (BIA) identifies and evaluates the potential effects of business process interruptions. When moving to the cloud, the BIA must be updated to include the cloud provider's supply chain dependencies. This includes the provider's utilities (power, cooling), suppliers (hardware), and vendors (network connectivity), as a failure in any of these can directly impact the customer's service. However, a cloud provider's reseller is part of the sales and marketing channel, not the operational service delivery chain. While a reseller's failure might create contractual or billing issues, it does not directly affect the continuity of the cloud service itself, making it an exception in a BIA.

A. The provider's utilities are a critical operational dependency; their failure would cause a service outage and must be considered in a BIA.

B. The provider's suppliers are part of the supply chain; their failure can impact the provider's ability to maintain or expand the service.

D. The provider's vendors, such as network carriers, are crucial dependencies whose failure can directly disrupt the cloud service.

1. Cloud Security Alliance (CSA). (2017). Security Guidance for Critical Areas of Focus in Cloud Computing v4.0. Page 466 discusses supply chain risk, stating, "The cloud customer should understand the cloud provider’s supply chain and related risks... This includes any dependencies the provider has on other services or providers." This highlights the importance of operational dependencies like vendors and suppliers, but not sales channels like resellers.

2. National Institute of Standards and Technology (NIST). (2010). NIST Special Publication 800-34 Rev. 1, Contingency Planning Guide for Federal Information Systems. Section 2.2.2, page 13, explains that a BIA must identify "dependencies on other systems or processes," which for a cloud customer includes the provider's operational dependencies.

3. OWASP. (2017). OWASP Top 10 - 2017, A9:2017-Using Components with Known Vulnerabilities. While focused on software, the principle applies to supply chains: organizations are responsible for understanding risks from all components, including third-party dependencies. This extends to a cloud provider's operational vendors but not typically their sales partners.