Search every question across sub-FAQs

ISO/IEC 27017:2015 sets no universal control-review interval. Set one from risk and applicable requirements, then review whenever the service model, feature set, service tier, provider chain, architecture, data location, agreement, assurance report, or customer requirement changes.

Also review after a relevant incident, failed restore, access finding, or monitoring gap. Update the responsibility matrix, configuration baseline, risk treatment, and evidence request together.

Define the required event categories and fields before comparing services. Include security-relevant identity and access events, customer and provider administrative actions visible to the customer, configuration changes, application and workload events, and incident-relevant service events where they apply. The customer should verify that the named service and tier meet those requirements; the provider should supply logging capabilities. In IaaS, the provider's responsibility can stop at infrastructure components while the customer logs its own virtual machines and applications.

Apply a separate branch to delegated privileged operations. Clause 12.4.3 says the operation and its performance should be logged, and the customer should decide whether provider logging is appropriate or whether additional customer logging is needed. Ask which clock the provider uses and how customer systems can synchronize to it; without synchronization, events from both sides can be difficult to reconcile.

Treat service monitoring as a capability built on records and service signals, not as another name for a log. CLD.12.4.5 says the provider should document capabilities that let the customer monitor specified aspects relevant to its use, such as detecting use of the service to attack others or leakage of sensitive data. Access should expose only the customer's own service instances, the monitoring data should be consistent with event logs, and it should help assess service-level terms.

Set event retention, protection, export delay, alert thresholds, and response times from the customer's risks, incident needs, laws, contracts, records rules, and technical constraints. ISO/IEC 27017:2015 does not supply one retention number or require a particular monitoring product.

Keep the approved logging requirements, service-specific allocation, provider capability description, enabled-event configuration, access list, retention and protection settings, clock information, export or integration status, alert rules, service-level mapping, and investigation procedure. Preserve evidence of configuration and operation; a provider feature list proves availability, not enablement or successful receipt.

Run a known-event test through the complete path. Record the source event, actor and resource, provider and customer timestamps, receipt time, expected and actual fields, tenant boundary, alert result, analyst action, escalation, retained record, and dropped or delayed data. Repeat separately for infrastructure, workload, application, or privileged sources when different parties or pipelines handle them.

ISO/IEC 27017 allocates customer and provider duties but does not prescribe internal approval titles. As a practical model, the cloud service owner and security monitoring owner can approve the event set and responsibility split, platform or application owners can operate customer logging, and supplier management can maintain provider commitments.

Include privacy, records, legal, or regulatory owners when they set retention, access, or disclosure constraints. The authorized risk owner decides whether an unresolved visibility gap is acceptable.

ISO/IEC 27017:2015 sets no fixed logging-review period. Review after service, tier, architecture, event schema, retention, export, alerting, provider, or incident-process changes. Repeat the known-event test after integrations or clock settings change.

Also review after an incident reveals missing, inaccessible, late, or ambiguous records. Update the agreement, responsibility matrix, monitoring procedure, and risk treatment together.

List the provider claims that affect service approval, such as implementation of named controls, compliance with applicable contractual or legal requirements, data location, isolation, backup, incident handling, or continuity. Request a document that substantiates each claim. Clause 18.1.1 says the provider should identify the jurisdictions governing the service and provide current compliance evidence when requested; the customer should consider both provider and customer jurisdictions.

Apply the clause 18.2.1 evidence sequence. A relevant independent audit selected by the provider is normally acceptable when it gives sufficient transparency and individual customer audits are impractical or could increase security risk. If an independent audit is impractical, the provider should conduct a self-assessment and disclose its process and results. Certification is one possible form of evidence, not the only route and not proof beyond its stated scope.

Check the provider legal entity, named services and tiers, locations, assessment criteria, control period or point-in-time date, exclusions, upstream or subservice organizations, auditor opinion, exceptions, and complementary customer controls. For any gap between the evidence period and the current decision, ask what later events or changes the provider attests to and record the limits. A certificate, audit report, self-assessment, or bridge letter supports only the claims its wording and scope cover.

Keep the assurance document, scope statement, assessment criteria, auditor or assessor identity and opinion, exceptions, provider response, later-period evidence, and customer assessment together. Record which provider claims were accepted, qualified, or rejected; why; and which provider remediation or customer control remains necessary.

Trace each relied-on claim to a page, control, system description, exception response, or other precise location in the evidence. Provider evidence does not show that the customer enabled a setting, reviewed access, collected customer logs, tested restoration, or met a legal duty. Link customer-operated controls to their own configuration exports, tickets, logs, test results, and approvals.

ISO/IEC 27017 does not prescribe the customer's internal approver titles. As a practical model, the cloud service owner can accept the provider-evidence assessment with security and supplier-assurance input. The person accepting residual risk must have the authority assigned by the customer's governance process.

Include privacy, legal, resilience, or regulatory owners when the evidence is being used to support their requirements. Do not treat the provider, its auditor, or a certificate issuer as approving the customer's use of the service.

ISO/IEC 27017:2015 sets no universal evidence cycle. Review when a new report is issued and when the provider entity, service, region, upstream or subservice organization, architecture, agreement, assurance scope, auditor conclusion, or material exception changes.

Reassess after a relevant incident or when bridge coverage expires. If current evidence is unavailable, document the gap, interim evidence, compensating controls, owner, deadline, and risk decision.

Build the allocation for one customer entity, provider entity, named service and tier, service model, region, current architecture, and provider chain. For each task, record the actor, action, input, handoff, evidence, exception route, and outcome. Clause 6.1.1 says the parties should agree their roles, state them in an agreement, and confirm that the customer can fulfil its allocation. CLD.6.3.1 adds that shared roles should be documented, communicated, and implemented by both sides.

Map identity, customer and provider administration, configuration, vulnerability handling, event logging, monitoring, backup, incident response, digital evidence, data and record protection, provider change, continuity, and exit where relevant. Use provider-owned, customer-owned, or shared only after naming the work. For a shared backup row, for example, state whether the provider supplies snapshots or another capability, who selects scope and retention, who initiates or automates backup, who protects access, who performs restoration, and who tests the result.

Use service-model examples as prompts, not fixed classifications. In IaaS, provider logging can be limited to infrastructure while the customer logs virtual machines and applications, and backup generally resides with the customer unless the provider offers it. In PaaS and SaaS, the provider can operate more layers, but the customer still owns its service decision, customer identities and available settings, customer procedures, and agreed handoffs.

Trace inherited duties through upstream providers. An organization can buy infrastructure as a customer while supplying its own application service as a provider. ISO/IEC 27017 says a provider using peer cloud services should maintain or exceed the information-security levels promised to its own customers and pass security objectives into the supply chain. An upstream dependency does not erase the direct provider's downstream commitment.

Keep the executed agreement and incorporated versions, service-specific responsibility matrix, provider documentation, customer procedures, configuration evidence, access and logging reviews, incident contacts, backup specifications and restore tests, change records, assurance material, and exit plan as applicable.

Test the highest-risk handoffs and at least one routine handoff. Trace a provider alert to customer receipt and response, a provider backup capability to the customer's restore test, or a provider change notice to customer impact assessment. Record the service, trigger, owners, expected data and timing, observed result, exception, follow-up owner, and due date.

ISO/IEC 27017 does not prescribe internal approval titles. As a practical model, the cloud service owner can approve the complete allocation, each customer control owner can accept the activities assigned to that team, and supplier management can maintain provider and upstream commitments.

Security should challenge gaps and inconsistent allocations. Include privacy, legal, resilience, or regulatory owners when their requirements apply, and send unresolved gaps to the authorized risk owner.

ISO/IEC 27017:2015 sets no universal review interval. Set one from risk and applicable requirements, then review when the service model, tier, provider chain, architecture, data location, agreement, provider capability, assurance scope, or customer operating model changes.

Also review after an incident or failed handoff exposes an incorrect assumption. Update the agreement, matrix, procedures, risk treatment, and evidence links together so they describe the same boundary.

Apply three separate tests. First, if the service is multi-tenant, CLD.9.5.1 assigns the provider logical segregation of customer data, virtualized applications, operating systems, storage, and networks between tenants and from the provider's internal administration. The customer should define its segregation requirements and obtain evidence for the named service, tier, region, and architecture. A dedicated service may change the tenant-isolation test, but it does not remove access-control, hardening, administration, or network-policy duties.

Second, identify who configures each virtual machine. CLD.9.5.2 tells customers and providers to harden the machines they configure for business needs, including allowing only needed ports, protocols, and services and applying appropriate measures such as anti-malware and logging. In an IaaS service, the customer commonly configures guest machines; in a managed platform or SaaS service, the provider may control the layer. Allocate images, snapshots, dormant or offline instances, guest operating systems, hypervisor exposure, self-service portals, and backups separately because the service label does not settle every layer.

Third, map the virtual network. CLD.13.1.4 assigns the provider the policy and verification duty: the provider should define a virtual-network security policy consistent with its physical-network policy and ensure that virtual configuration matches it regardless of how the configuration is created. The standard notes that the party configuring the virtual network can vary by service type. Customer-configurable rules still need a named customer owner and evidence, but the provider's stated consistency duty should not be reassigned solely because the customer enters the rule.

Document customer critical operations whose failure could cause unrecoverable damage, including installing, changing, or deleting virtual servers, networks, or storage; terminating cloud use; and backup or restoration. CLD.12.1.5 says the customer procedure should specify supervisor monitoring, while the provider should supply critical-operation documentation to customers who require it.

Keep the current service architecture, tenancy statement, layer-by-layer responsibility matrix, provider segregation assurance, customer and provider virtual-machine baselines where available, image controls, snapshot and dormant-instance inventory, virtual and physical network-policy mapping, privileged-operation logs, critical-operation procedure, and backup and restoration results.

Sample one active virtual machine, image or snapshot, virtual-network rule set, isolation control claim, and critical administrative operation where each exists. Record the service and resource, configuring party, expected baseline or policy, observed result, evidence period, owner, reviewer, exception, follow-up owner, and due date.