Cloud environments pose many unique challenges for a data custodian to properly adhere to policies and the use of data. What poses the biggest challenge for a data custodian with a PaaS…

Access to systems is indeed more limited by design in PaaS than in IaaS, but the primary challenge for the data custodian stems from the lack of direct knowledge and control over the managed components.

In a PaaS implementation, the cloud provider manages the operating systems, middleware, and runtime environments, abstracting these layers from the customer. This abstraction reduces the customer's visibility and direct control over the underlying infrastructure, thus posing a greater challenge for the data custodian to have full knowledge of the systems compared to IaaS, where the customer manages more layers.

Data classification rules are primarily the responsibility of the cloud customer across all cloud models (IaaS, PaaS, SaaS) and are not inherently more challenging in PaaS than in IaaS.

Contractual requirements are a challenge in any cloud model, but they relate to legal agreements, not the direct technical challenges of managing data within a specific cloud service model.