Large organisations should treat identity as a shared control plane rather than a set of isolated tools. Start by inventorying authentication and authorization patterns, then standardize policy, federation, and lifecycle processes around a central identity layer. This reduces inconsistency, improves auditability, and makes it easier to support diverse application needs without multiplying operational risk.
Why This Matters for Security Teams
Centralizing identity across cloud and on-premise applications is not just an admin exercise. It is how large organisations reduce credential sprawl, enforce consistent access policy, and get a reliable audit trail across systems that were never designed to agree with one another. Without a shared identity control plane, teams end up compensating with local accounts, duplicate directories, and ad hoc exceptions that weaken both governance and incident response.
The problem is especially acute where non-human identities are involved. NHIMG’s Ultimate Guide to NHIs notes that 97% of NHIs carry excessive privileges, which is a strong signal that identity fragmentation is not a theoretical risk. The right model is closer to a control plane than a collection of point tools, and that aligns with the intent of the NIST Cybersecurity Framework 2.0, which emphasizes governance, protection, and continuous oversight across assets and services.
In practice, many security teams discover identity sprawl only after an audit finding, an access review failure, or a breach involving an over-privileged service account, rather than through deliberate design.
How It Works in Practice
Centralization works best when organisations separate the identity source of truth from the applications that consume it. A common pattern is to standardize workforce identity in one directory, then federate authentication into cloud and on-premise applications through SSO, SAML, OIDC, or Kerberos where appropriate. That does not mean every app must be forced into the same protocol immediately. It means access decisions, lifecycle events, and policy enforcement are anchored in one governance model.
For NHIs, the same logic applies but the mechanics differ. Service accounts, workload identities, API keys, and certificates should be managed centrally with lifecycle controls for issuance, rotation, revocation, and expiry. NHIMG’s NHI Lifecycle Management Guide and Ultimate Guide to NHIs — Lifecycle Processes for Managing NHIs both reinforce that lifecycle discipline is where centralized identity either becomes operationally useful or collapses into a reporting layer only.
A practical implementation model usually includes:
- A single identity governance source for joiner, mover, leaver, and machine-to-machine lifecycle events.
- Federated authentication into cloud and legacy apps instead of local credentials wherever possible.
- Central policy decisions for RBAC, conditional access, and privileged access workflows.
- Separate handling for human and non-human identities, because service accounts do not behave like employees.
- Automated deprovisioning and rotation so access does not outlive business need.
The operational test is simple: if an app cannot consume central policy or identity assertions, it should be treated as an exception with compensating controls, not as evidence that decentralization is acceptable. These controls tend to break down in heavily customized legacy environments where applications cannot support federation and administrators keep local break-glass accounts as the default operating model.
Common Variations and Edge Cases
Tighter identity centralization often increases migration effort, especially when the estate includes mainframes, older ERP systems, acquired business units, or applications that only understand local usernames and passwords. Organisations need to balance consistency against downtime risk and the operational reality that not every system can be modernized at once.
Current guidance suggests using a tiered approach. High-value cloud services, privileged access paths, and systems exposed to third parties should move first to central federation and centralized lifecycle management. Lower-risk or technically constrained systems can remain temporarily outside the core model, but only with explicit exception handling and time-bound remediation plans. That is also where the distinction between human and NHI governance matters most: machine identities often need short-lived credentials, workload-bound trust, and tighter scope than traditional user accounts.
For organisations still untangling identity sprawl, the clearest warning signs are duplicated directories, unowned service accounts, and secrets stored outside managed systems. NHIMG’s Top 10 NHI Issues highlights how quickly these gaps become systemic. In parallel, NIST’s NIST SP 800-53 Rev 5 Security and Privacy Controls supports the underlying control objective: identity should be governed, auditable, and limited to what each subject actually needs.
There is no universal standard for how quickly every legacy application must be integrated, but the central principle is settled: identity should be managed as a shared control plane, while exceptions should shrink over time rather than become permanent architecture.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 address the attack and risk surface, while NIST CSF 2.0 and NIST SP 800-53 Rev 5 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST CSF 2.0 | PR.AC-1 | Central identity governance supports consistent access control across environments. |
| OWASP Non-Human Identity Top 10 | NHI-01 | Identity sprawl and unmanaged service accounts are core NHI governance risks. |
| NIST SP 800-53 Rev 5 | AC-2 | Account lifecycle control is required to prevent orphaned or duplicate identities. |
Centralize identity policy and enforce authenticated access through one governed control plane.
Related resources from NHI Mgmt Group
- Why do large organisations struggle to onboard business applications into identity security workflows?
- How should organisations approach identity governance when business applications, cloud infrastructure, and data access are all converging?
- How should organisations enforce identity governance across multi-cloud and AI-driven workflows?
- How should organisations centralise authorization decisions across cloud, mobile, and legacy applications?
