SC-48(1): Dynamic Relocation of Sensors or Monitoring Capabilities

SC-48(1) requires you to dynamically move network sensors or monitoring capabilities between locations based on defined trigger conditions, so attackers cannot predict or evade detection. To operationalize it, define what “sensors” you will relocate, where they can move, what triggers the move, and how you prove moves happened without breaking coverage. (NIST SP 800-53 Rev. 5 OSCAL JSON)

Key takeaways:

• Define the relocatable monitoring set (tools, telemetry, placements) and the allowed destination set before you automate anything. (NIST SP 800-53 Rev. 5 OSCAL JSON)
• Hard-code relocation triggers (risk signals, events, schedules) and document decision logic so auditors can test it. (NIST SP 800-53 Rev. 5 OSCAL JSON)
• Preserve evidence: relocation run logs, coverage validation results, and change approvals tied to your triggers. (NIST SP 800-53 Rev. 5)

Dynamic relocation sounds exotic, but SC-48(1) is a practical anti-evasion requirement: if monitoring stays in the same place, a capable adversary can map it, route around it, or craft traffic that avoids your detection points. The control enhancement pushes you to treat sensor placement as adaptive, not static, by moving sensors (or their effective monitoring capability) to different network vantage points when specific conditions occur. (NIST SP 800-53 Rev. 5)

For a Compliance Officer, CCO, or GRC lead, the fastest path to operationalization is to translate SC-48(1) into three concrete decisions your teams can implement and you can audit: (1) which monitoring capabilities are eligible to move, (2) where they are allowed to move, and (3) what conditions trigger a move. Once those are set, your implementation becomes a repeatable procedure owned by Security Engineering/Network Engineering, governed through change management, and evidenced through logs and validation tests. (NIST SP 800-53 Rev. 5 OSCAL JSON)

This page gives requirement-level guidance you can drop into your control narrative, assign to an owner, and turn into testable evidence for assessments aligned to NIST SP 800-53 Rev. 5. (NIST SP 800-53 Rev. 5)

Regulatory text

Requirement (excerpt): “Dynamically relocate {{ insert: param, sc-48.01_odp.01 }} to {{ insert: param, sc-48.01_odp.02 }} under the following conditions or circumstances: {{ insert: param, sc-48.01_odp.03 }}.” (NIST SP 800-53 Rev. 5 OSCAL JSON)

What the operator must do with this text

SC-48(1) is intentionally parameterized. Your job is to fill in, approve, and operate three organization-defined parameters (ODPs): (1) what you are relocating, (2) where you relocate it to, and (3) the conditions that cause relocation. If you cannot point to those three decisions in writing and show operational records that relocation occurs under those conditions, you will struggle to demonstrate implementation. (NIST SP 800-53 Rev. 5 OSCAL JSON)

A workable interpretation is:

• ODP #1 (what): a defined set of sensors or monitoring capabilities (for example, NIDS sensors, packet capture points, egress taps, host-based telemetry collectors, cloud flow logs routed to different analytics paths).
• ODP #2 (where): a defined set of alternative placements/vantage points (for example, different VLAN trunks, different cloud subnets/VPCs, different SPAN ports, different gateways, alternate host groups).
• ODP #3 (when): defined triggers (for example, threat intel raises, active incident response, detection of scanning, major topology change, or at a defined cadence you set). (NIST SP 800-53 Rev. 5 OSCAL JSON)

Plain-English interpretation of the requirement

You must be able to move your monitoring coverage in a controlled, pre-planned way, based on specific triggers, so monitoring placement is less predictable and more resilient to attacker evasion. “Dynamic” does not require constant motion; it requires that relocation can occur promptly when your defined conditions occur, and that the relocation is governed, tested, and evidenced. (NIST SP 800-53 Rev. 5)

A key nuance for auditors: “relocation of sensors” can be satisfied by relocating the capability, not necessarily a physical appliance. In cloud and virtualized environments, that often means changing where traffic is mirrored, what workloads run enhanced logging/EDR policies, or how telemetry routes into analytics. Your narrative should make that explicit. (NIST SP 800-53 Rev. 5)

Who it applies to (entity and operational context)

SC-48(1) is relevant when you claim alignment to NIST SP 800-53 Rev. 5 for:

• Federal information systems and programs using NIST 800-53 as the control baseline. (NIST SP 800-53 Rev. 5)
• Contractor systems handling federal data where NIST 800-53 controls are contractually required or inherited via program requirements. (NIST SP 800-53 Rev. 5)

Operational contexts where this control becomes “real” quickly:

• Networks with multiple monitoring vantage points (branch, data center, cloud, OT enclaves).
• Environments where adversaries may attempt evasion by learning your sensor locations (high-value targets, segmented enclaves, externally exposed services).
• Programs with strong assessment expectations (ATO packages, continuous monitoring). (NIST SP 800-53 Rev. 5)

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

Use this as an implementation checklist you can assign and track.

Step 1: Name the control owner and approval path

• Assign a primary control owner (often Security Engineering or Detection Engineering).
• Assign network/cloud platform approvers who can authorize movement of taps/mirroring/log routes.
• Define when relocation is a standard change vs. emergency change under incident response. (NIST SP 800-53 Rev. 5)

Step 2: Define ODP #1 — the “relocatable monitoring set”

Create an inventory list with:

• Sensor/capability name (tool + deployment type).
• What it sees (north-south, east-west, egress, identity, endpoint).
• Dependencies (SPAN ports, agents, IAM roles, collectors).
• Minimum coverage requirements you will not violate. (NIST SP 800-53 Rev. 5 OSCAL JSON)

Practical tip: auditors test scope boundaries. If only some monitoring can relocate, write that clearly and explain why.

Step 3: Define ODP #2 — allowed destinations/vantage points

Document:

• Approved destination segments/subnets/accounts/sites.
• Constraints (bandwidth, privacy boundaries, regulated zones).
• “No-go” zones where relocation is prohibited. (NIST SP 800-53 Rev. 5 OSCAL JSON)

Deliverable: a simple matrix:

Sensor/capability	Allowed destinations	Coverage invariant	Approval needed

Step 4: Define ODP #3 — relocation triggers and decision logic

Choose triggers that your program can execute and evidence. Examples you can adapt:

• Incident declared for a defined severity threshold.
• Detection of reconnaissance/scanning patterns in an enclave.
• Material network topology change.
• Red team/exercise window requiring altered visibility.
• Time-based cadence you set for unpredictability. (NIST SP 800-53 Rev. 5 OSCAL JSON)

Write the logic as “IF trigger, THEN relocate from A to B (or select from set), THEN validate coverage.”

Step 5: Engineer the relocation mechanism

Your implementation can be:

• Automated (SOAR playbooks, infrastructure-as-code that changes mirroring routes, policy-based routing of logs).
• Semi-automated (runbooks executed by network/SOC with pre-approved changes). (NIST SP 800-53 Rev. 5)

Minimum expectation: relocation is feasible, repeatable, and produces logs.

Step 6: Validate coverage after each relocation

Define post-move checks:

• Sensor health (heartbeat, ingestion rate trending, alert pipeline functioning).
• Test events (benign simulated traffic or known test signatures).
• Confirm no “blind window” beyond what your risk acceptance allows. (NIST SP 800-53 Rev. 5)

Step 7: Operationalize through change management and continuous monitoring

• Tie relocations to change tickets (standard or emergency).
• Add relocation events to your continuous monitoring dashboard.
• Review relocation history periodically to confirm triggers are firing and changes are not purely ad hoc. (NIST SP 800-53 Rev. 5)

Step 8: Map to control narrative and recurring evidence

Make the control assessable:

• One-page procedure.
• Trigger list.
• Destination list.
• Evidence list and frequency. This is where Daydream fits naturally: track ownership, procedures, and recurring evidence artifacts so SC-48(1) stays audit-ready even as your network changes. (NIST SP 800-53 Rev. 5 OSCAL JSON)

Required evidence and artifacts to retain

Keep evidence that proves design and operation.

Design artifacts

• SC-48(1) control narrative with filled ODPs (what/where/when). (NIST SP 800-53 Rev. 5 OSCAL JSON)
• Sensor inventory and destination matrix.
• Runbooks or automation playbooks for relocation.
• Risk acceptance documentation if some areas cannot support relocation.

Operational artifacts

• Change tickets or incident records authorizing each relocation.
• System logs showing relocation execution (automation logs, device configs, mirroring changes).
• Post-relocation validation results (sensor health checks, test events).
• Periodic review notes showing governance of the process. (NIST SP 800-53 Rev. 5)

Common exam/audit questions and hangups

Expect assessors to ask:

• “Show me the defined conditions that trigger relocation and an example where it occurred.” (NIST SP 800-53 Rev. 5 OSCAL JSON)
• “What exactly is being relocated: hardware sensors, virtual sensors, mirroring configuration, log routing?” (NIST SP 800-53 Rev. 5)
• “How do you ensure relocation doesn’t create monitoring gaps?” (NIST SP 800-53 Rev. 5)
• “Who approves relocation, and is it recorded in change management?” (NIST SP 800-53 Rev. 5)
• “Is relocation limited to one environment (cloud only), and if so, what compensates elsewhere?” (NIST SP 800-53 Rev. 5)

Hangup pattern: teams claim “we can redeploy sensors anytime” but cannot show triggers, actual moves, or validation.

Frequent implementation mistakes and how to avoid them

1. Defining ‘dynamic’ as ‘we moved it once.’
   Fix: define triggers and show multiple instances over time tied to those triggers. (NIST SP 800-53 Rev. 5)

2. Treating relocation as a network project, not a control with evidence.
   Fix: make logs + tickets mandatory outputs of the procedure. (NIST SP 800-53 Rev. 5)

3. Relocating without proving equivalent detection coverage.
   Fix: require post-move validation tests and document “coverage invariants” per sensor. (NIST SP 800-53 Rev. 5)

4. No approved destination list.
   Fix: create an allowlist of destinations and enforce it through configuration standards and peer review. (NIST SP 800-53 Rev. 5 OSCAL JSON)

5. Cloud ambiguity (“sensors” vs. “logging”).
   Fix: define “monitoring capabilities” broadly in your ODP #1 to include log sources and routing patterns. (NIST SP 800-53 Rev. 5)

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for this requirement, so you should treat SC-48(1) primarily as an assessment and mission risk item rather than a penalty-driven obligation. The practical risk is detection evasion: static monitoring placements are easier to map, and predictable visibility reduces your ability to contain and investigate intrusions. (NIST SP 800-53 Rev. 5)

Practical 30/60/90-day execution plan

Use staged phases (not calendar-day promises) to keep this implementable across environments.

First 30 days (Immediate foundation)

• Assign owner(s) and approvers; document RACI for relocation actions. (NIST SP 800-53 Rev. 5)
• Draft SC-48(1) ODPs: relocatable set, destination set, trigger set. (NIST SP 800-53 Rev. 5 OSCAL JSON)
• Build the sensor/destination matrix and identify technical blockers (SPAN scarcity, IAM limits, privacy constraints).

Days 31–60 (Implement and test)

• Write runbooks or automation for the top-priority relocation scenarios.
• Integrate relocation into change management (standard change template for planned moves; emergency path for incidents). (NIST SP 800-53 Rev. 5)
• Define and run post-relocation validation checks; store results as evidence.

Days 61–90 (Operationalize and make it auditable)

• Run at least one relocation exercise per trigger category you defined (planned + incident-driven) and capture the full evidence chain. (NIST SP 800-53 Rev. 5 OSCAL JSON)
• Add periodic review: confirm triggers are still relevant as architecture changes.
• Centralize evidence collection and control mapping (Daydream can track the owner, procedure version, and recurring artifacts so assessment prep is a pull, not a scramble). (NIST SP 800-53 Rev. 5)

Frequently Asked Questions

Does SC-48(1) require physically moving hardware sensors?

No. The text allows relocation of “sensors or monitoring capabilities,” so changing virtual placements, mirroring points, or log routing can satisfy the intent if documented and evidenced. (NIST SP 800-53 Rev. 5 OSCAL JSON)

What counts as “dynamic” for auditors?

“Dynamic” should be tied to defined trigger conditions and repeatable execution. Auditors commonly expect to see at least one real instance mapped to your triggers, plus validation that coverage remained acceptable. (NIST SP 800-53 Rev. 5)

Can we limit relocation to high-risk segments only?

Yes, if you define the scope in your ODPs and document rationale and any compensating monitoring for segments that cannot support relocation. Keep the boundary explicit in your control narrative. (NIST SP 800-53 Rev. 5 OSCAL JSON)

How do we prove relocation happened?

Retain change records or incident records, automation/run logs showing what changed, and post-change sensor health/coverage checks. Screenshots alone are fragile; prefer system-generated logs. (NIST SP 800-53 Rev. 5)

What if relocation causes a monitoring gap due to capacity limits?

Treat that as a design constraint: define coverage invariants, only allow destinations that meet them, and document risk acceptance when temporary gaps are unavoidable under emergency change. (NIST SP 800-53 Rev. 5)

How should GRC teams track this control over time?

Track ODP decisions, procedure versions, and recurring evidence in a single system of record so assessment support does not depend on individual engineers. Daydream is a practical fit for mapping ownership, procedures, and evidence artifacts to SC-48(1). (NIST SP 800-53 Rev. 5 OSCAL JSON)