OPS-31 Separation of Datasets - Implementation
Changed since C5:2020 · formerly OPS-24
Basic criterion
Linked criterion to the newly included guideline for the separation of data sets and to the policy for the use of cryptographic mechanisms.
Added requirement for reviewing the risk assessment in regards to the data separation.
Additional criterion
Additional criterion removed.
Wording in C5:2020
Basic criterion
Cloud customer data stored and processed on shared virtual and physical resources is securely and strictly separated according to a documented approach based on OIS-07 risk analysis to ensure the confidentiality and integrity of this data.
Additional criterion
Resources in the storage network are segmented by secure zoning (LUN binding and LUN masking).
Basic criterion
The cloud service provider designs, implements and maintains measures and procedures against threats to the separation of data sets according to the policies and procedures of OPS-30. The measures address prevention against, detection of and reaction to any incidents infringing the separation.
Cloud service customer data stored and processed on shared virtual and physical resources is securely and strictly separated according to a documented approach based on OIS-07 risk assessment and following policies on cryptography (cf. CRY-01) to ensure the confidentiality and integrity of this data.
Supplementary information
Shared resources include CPU, RAM, storage space and networks. The separation of cloud service customer data on shared resources can take place, for example, in accordance with cloud layers described in the *CISA Cloud Security Technical Reference Architecture*. The separation on each shared resource is implemented as deemed appropriate based on the conducted risk assessment, which might also include not implementing a cryptographic separation for certain shared resources.
Where the adequacy and effectiveness of separation cannot be assessed with reasonable assurance (e.g. due to complex implementation), evidence may also be provided through expert third-party review results (e.g. penetration tests to validate the policies and procedures).
The separation of transmitted data is subject to criterion COS-06.
The risk assessment is reviewed as needed, especially in case of changes to the architecture of the cloud service, and at least annually. Measures are adjusted or improved as appropriate to ensure they remain commensurate with the risks.
Complementary customer criteria
What cloud service customers implement on their side.
Cloud service customers ensure with suitable controls that the functions provided by the cloud service for separating shared virtual and physical resources are used in such way that risks related to separation are adequately addressed according to the data's protection needs.
Related criteria
BSI text from C5:2026 and its changelog: © Federal Office for Information Security 2026, reproduced unchanged under CC BY-ND 4.0. Unofficial site, not affiliated with BSI. Licence and sources