Shared responsibility communications

“Shared responsibility” fails in real environments for one reason: everyone assumes the other side owns the control. ISO/IEC 27017 is explicit that cloud security obligations must be communicated clearly between provider and customer ¹. For a CCO or GRC lead, this is a requirement you can operationalize quickly if you treat it like a product deliverable with lifecycle management, not a one-time policy memo.

This requirement shows up during audits as a deceptively simple question: “Where do you define and communicate security responsibilities to customers?” If your answer is “it’s in the MSA somewhere,” expect follow-ups on clarity, completeness by service, and whether updates are communicated when features, configurations, or control boundaries change.

This page gives requirement-level guidance: who must comply, what to build, how to roll it into contracting and operations, and what evidence auditors ask for. The goal is practical execution: customers understand their duties, your teams know what you own, and you can prove both facts with artifacts that hold up under scrutiny.

Requirement: shared responsibility communications (ISO/IEC 27017)

ISO/IEC 27017 focuses on cloud security controls and guidance for both cloud service providers and cloud customers. The shared responsibility communications requirement expects clear communication of security obligations between the provider and the customer ¹.

Plain-English interpretation

You must:

1. Define which party is responsible for which security controls (and control steps) for each cloud service you offer or consume.
2. Communicate those responsibilities in a form that the other party can reasonably understand and act on.
3. Keep the communication accurate over time as the service, architecture, threat model, or contractual scope changes.

“Clearly” means more than publishing a diagram. It means a customer can determine, for a given feature (example: customer-managed keys, audit logging, backups), what they must configure and what you operate by default, plus what happens if they do nothing.

Who it applies to (entity and operational context)

Applies to:

• Cloud service providers (CSPs): SaaS, PaaS, IaaS providers, managed service providers offering cloud-hosted services, and any provider exposing customer-configurable security features.
• Cloud customers: organizations consuming cloud services where some controls shift to the customer (identity, configuration, data classification, endpoint security, tenant logging, key management, etc.).

Operational contexts where auditors focus:

• Regulated customers (financial services, healthcare, critical infrastructure) asking for control ownership clarity during due diligence.
• Multi-tenant environments, where configuration errors can become customer-impacting incidents.
• Any service that ships security-sensitive features frequently (new auth modes, logging changes, new data stores, new integrations).

Regulatory text

Provided excerpt (summary record): “Baseline implementation-intent summary derived from publicly available framework overviews; licensed standard text is not reproduced in this record.” The requirement intent is: “Communicate security obligations between provider and customer clearly.” ¹

What the operator must do:

• Produce an explicit, customer-facing description of the division of security responsibilities.
• Make it easy to access (sales cycle, onboarding, ongoing operations).
• Maintain it through change management so customers receive timely updates that affect their risk or required actions.

What you actually need to do (step-by-step)

Treat this like a controlled document plus a distribution workflow.

Step 1: Define the “responsibility taxonomy” you will use

Pick simple, repeatable categories that map to how you run the service:

• Provider-owned: you design, implement, operate, monitor, and test.
• Customer-owned: customer configures/operates in their tenant or environment.
• Shared: both sides have discrete tasks (spell out tasks, not just the label).
• Inherited/covered by provider: customer gets the control outcome automatically, with assumptions and boundaries.

Add a required field for “customer action required” and “default state” (example: “audit logs off by default; customer must enable”).

Step 2: Build a shared responsibility model per service (not one global poster)

Create a matrix that maps major control domains to your service features. Minimum domains most teams include:

• Identity and access management
• Logging and monitoring
• Vulnerability and patch management
• Encryption and key management
• Backup/restore and availability
• Network security boundaries
• Incident response coordination
• Data lifecycle (retention, deletion, eDiscovery support)

Deliverable: a versioned “Shared Responsibility Model” document, plus service-specific annexes if you have multiple products.

Step 3: Bind the model to contracting artifacts

Your lawyers and procurement teams need the same source of truth.

• Map the matrix to contract language: security addendum, DPA, acceptable use, and SLAs.
• Align terms with what your service actually does by default.
• Add explicit clauses for shared tasks that customers routinely miss (example: customer must configure SSO, MFA, IP allowlists, log export destinations).

Practical control: your contract template should reference the shared responsibility documentation by name and version (or by a controlled URL that is versioned).

Step 4: Operationalize customer communication (beyond posting a PDF)

You need at least three communication paths:

1. Pre-sale / due diligence: security package that includes the responsibility model.
2. Onboarding: checklist or admin guide that turns responsibilities into setup tasks.
3. Ongoing changes: release notes + security advisory process that flags responsibility boundary changes.

A clean pattern is:

• “Shared Responsibility Model” (stable)
• “Customer Security Configuration Guide” (actionable)
• “Security Change Notices” (time-sensitive deltas)

Step 5: Add internal alignment so delivery teams don’t contradict the model

Misalignment between sales, support, and security is a common audit failure mode.

• Train customer-facing teams (sales engineers, CSMs, support) on the model.
• Add a standard script: “We own X; you must configure Y; here’s where it’s documented.”
• Require exceptions to go through risk acceptance (example: promising a control you do not actually operate).

Step 6: Put the model under change management

Tie updates to engineering change control:

• New features that touch auth, logging, encryption, admin roles, data export, integrations, or backups must trigger a review of the shared responsibility model.
• Security and GRC approve updates.
• Publish changes with a clear summary of customer action required.

Step 7: Validate effectiveness (prove “clear” in practice)

Use lightweight verification:

• Spot-check support tickets for repeated misunderstandings; treat patterns as documentation defects.
• Run onboarding completion checks (did customers enable MFA/logging if required?).
• Confirm that security advisories and documentation updates reach the right customer contacts.

Required evidence and artifacts to retain

Auditors typically want both the content and proof it is controlled and communicated.

Core artifacts

• Shared Responsibility Model (versioned; owner; approval history)
• Service-specific responsibility annexes (if applicable)
• Customer security configuration guide / hardening guide
• Contract templates referencing responsibility documentation (security addendum, DPA exhibits where relevant)
• Change management records linking product/security changes to documentation updates
• Customer communications: release notes, security advisories, or notices where responsibility boundaries changed
• Training evidence for customer-facing teams (materials + attendance or completion records)
• Customer onboarding checklist and completion evidence (where you track it)

Operational evidence

• Support macros or knowledge base links used by support
• Screenshots or access logs showing where the documentation is published (help center, trust portal, customer admin console)
• Periodic review records (document review tickets, approvals)

Common exam/audit questions and hangups

Questions you should be ready to answer

• “Show me where responsibilities are defined for identity, logging, encryption, backup, and incident response.”
• “How do you ensure customers receive updates when responsibilities change?”
• “Where in the contract do you describe responsibility boundaries?”
• “How do sales/support avoid making inconsistent promises?”
• “Show evidence this is reviewed and updated, not static.”

Typical hangups

• A single high-level diagram with no service-specific detail.
• Responsibilities described as “shared” without task-level breakdown.
• Documentation exists but is not referenced in onboarding or contracts.
• Updates happen in product releases but not in the responsibility documentation.

Frequent implementation mistakes (and how to avoid them)

1. Mistake: treating shared responsibility as marketing collateral.
   Avoidance: assign an accountable owner (usually Security/GRC) and require change control approvals.

2. Mistake: mixing “security features” with “security obligations.”
   Customers need obligations stated as tasks: “Enable MFA,” “Rotate keys,” “Configure log export,” not feature descriptions.

3. Mistake: writing one model for every product.
   Avoidance: create a base model plus per-service annexes. If a control differs by tier, spell it out by tier.

4. Mistake: no customer-action flags.
   Add “customer action required” fields so customers can operationalize quickly.

5. Mistake: contract says one thing, docs say another.
   Run a reconciliation review between legal, security, and engineering. Keep a single controlled source for responsibilities.

Enforcement context and risk implications

No public enforcement cases were provided in the supplied source catalog for this requirement. Practically, failures in shared responsibility communications increase:

• Security incident risk: customers misconfigure core settings (identity, logging, exposure).
• Contract and dispute risk: unclear responsibility boundaries drive post-incident conflict.
• Audit findings: auditors treat unclear ownership as a control design gap, especially when customer action is required for the control outcome.

Practical 30/60/90-day execution plan

First 30 days: establish the source of truth

• Inventory cloud services/products and identify where customers configure security-relevant settings.
• Draft a responsibility matrix for the top service(s) and top control domains.
• Decide where it will live (trust portal/help center/customer console) and how it will be versioned.
• Align with Legal on how contracts will reference it.
• Start a backlog of “known confusion points” from support and customer success.

Days 31–60: operationalize communication and governance

• Publish the initial Shared Responsibility Model and a customer configuration checklist.
• Add onboarding steps that map directly to “customer-owned” tasks.
• Train sales/support on the model and provide standard responses with links.
• Implement a change trigger: security review required for releases affecting auth, logging, encryption, backups, admin roles, integrations, or data flows.

Days 61–90: prove it works and close gaps

• Run a tabletop: pick a control (example: audit logging) and confirm everyone can answer “who does what” consistently.
• Sample customer implementations (or onboarding records) to confirm they complete required actions.
• Create a quarterly review cadence and document it.
• Use a system like Daydream to track responsibility documentation as a control with owners, review tasks, evidence collection, and audit-ready exports for customer due diligence.

Frequently Asked Questions

What level of detail is enough for the shared responsibility communications requirement?

Detail is sufficient when a customer can translate responsibilities into specific setup and operating tasks for your service. If you have “shared” controls, list each party’s tasks explicitly instead of using the “shared” label alone.

Do we need separate shared responsibility docs per product?

If control ownership differs by product, tier, deployment model, or feature set, you need product- or service-specific annexes. A single generic model usually creates ambiguity during audits and customer due diligence.

Where should we publish shared responsibility documentation?

Publish it where customers naturally go for security information (trust portal, help center, admin console), and ensure it is versioned and easy to reference in contracts and onboarding. The key test is whether customers can reliably find the current version.

How do we handle updates when a feature changes responsibility boundaries?

Route relevant releases through a trigger in change management that requires a documentation review and a customer notice if action is required. Keep evidence of the change, approval, and the outbound communication.

We’re the customer, not the provider. What does “shared responsibility communications” mean for us?

You still need to understand and document what you own versus what your cloud provider owns, then assign internal owners to the “customer-owned” tasks. Treat the provider’s model as an input to your control ownership matrix and operating procedures.

What evidence do auditors expect to prove the communication is “clear”?

Expect to show the published documentation, version history, contract references, onboarding materials, and change notices tied to releases. Auditors also ask for internal enablement evidence so sales/support do not contradict the documented responsibilities.

Related compliance topics

• 2025 SEC Marketing Rule Examination Focus Areas
• Access and identity controls
• Access Control (AC)
• Access control and identity discipline
• Access control lifecycle management

Footnotes

1. ISO/IEC 27017 overview