MON-22: Inbound & Outbound Communications Traffic
Mechanisms exist to continuously monitor inbound and outbound communications traffic for unusual or unauthorized activities or conditions.
Renumbered: Formerly MON-01.3 in SCF 2025.4.
Control Question: Does the organization continuously monitor inbound and outbound communications traffic for unusual or unauthorized activities or conditions?
General (25)
| Framework | Mapping Values |
|---|---|
| AICPA TSC 2017:2022 (used for SOC 2) (source) | CC7.2 |
| CSA IoT SCF 2 | CLS-07 OPA-04 OPA-08 |
| GovRAMP | SI-04(04) |
| GovRAMP Core | SI-04(04) |
| GovRAMP Moderate | SI-04(04) |
| GovRAMP High | SI-04(04) |
| IEC 62443-2-1 2024 | ORG 2.2(b) |
| ISO 27002 2022 | 8.16 |
| ISO 27018 2025 | 8.16 |
| MPA Content Security Program 5.3.1 | TS-1.5 TS-2.13 |
| NIST 800-53 R4 | SI-4(4) |
| NIST 800-53 R5.2 | SI-04(04) |
| NIST 800-53B R5 (moderate) (source) | SI-04(04) |
| NIST 800-53B R5 (high) (source) | SI-04(04) |
| NIST 800-82 R3 | SI-04(04) |
| NIST 800-82 R3 MODERATE OT Overlay | SI-04(04) |
| NIST 800-82 R3 HIGH OT Overlay | SI-04(04) |
| NIST 800-160 Vol2 R1 | SI-04(04) |
| NIST 800-171 R2 (source) | 3.14.6 |
| NIST 800-171 R3 (source) | 03.13.01.a 03.14.06.c |
| NIST 800-171A (source) | 3.14.6[a] 3.14.6[b] 3.14.6[c] |
| NIST 800-171A R3 (source) | A.03.13.01.a[01] A.03.13.01.a[03] A.03.14.06.b A.03.14.06.c[01] |
| NIST CSF 2.0 (source) | DE.CM-01 |
| OWASP Top 10 2025 | A01:2025 A09:2025 |
| SPARTA 4.0 | CM0073 |
US (16)
| Framework | Mapping Values |
|---|---|
| USA Federal CMS MARS-E 2.0 | SI-4(4) |
| USA Federal CISA CPG 2022 | 2.T |
| USA Federal DHS CISA SSDAF | 1.b.i |
| USA Federal C2M2 2.1 | SITUATION-2b |
| USA Federal CMMC 2.0 Level 2 | SIL2.-3.14.6 |
| USA Federal EO 14028 | 4e(i)(B) |
| USA Federal CJIS Security Policy 6.0 | SI-4(4) |
| USA Federal FFIEC ITEH 2016 | III.B |
| USA Federal FedRAMP R5 (moderate) | SI-04(04) |
| USA Federal FedRAMP R5 (high) | SI-04(04) |
| USA Federal IRS 1075 2021 | SI-4(CE-4).a SI-4(CE-4).b |
| USA Federal 33 CFR Part 101 Subpart F | 101.650(f)(3) 101.650(h)(2) |
| USA Federal TSA SDP 2021-02F | III.D.2.a III.D.2.b |
| USA Federal TSA / DHS 1580/82-2022-01 | III.D.2.a III.D.2.b |
| USA California CCPA 2025 | 7123(c)(8)(A) |
| USA Texas TX-RAMP Level 2 | SI-04 (04) |
EMEA (3)
| Framework | Mapping Values |
|---|---|
| EMEA Germany C5 2026 | COS-01.02B.1 COS-03.02B |
| EMEA EU DORA RTS 2024 | Article 12.2(c)(v) |
| EMEA EU NIS2 Annex 2024 | 3.2.3(a) |
APAC (5)
| Framework | Mapping Values |
|---|---|
| APAC Australia Essential 8 2024 | ISM-1906 ISM-1907 |
| APAC Australia ISM June 2026 | ISM-1906 ISM-1907 ISM-2015 |
| APAC Malaysia RMiT 2025 | A5-A4(g) A10-B10(b)(i) |
| APAC New Zealand NZISM 3.9 | 15.2.40.C.02 16.6.10.C.01 16.6.10.C.02 18.4.8.C.01 18.4.8.C.02 18.4.8.C.03 |
| APAC Singapore CCOP CII 2026 | 6.1.1(b) 6.1.1(c) 6.1.1(d) 6.1.2 10.2.2 12.4.3 |
Americas (1)
| Framework | Mapping Values |
|---|---|
| Americas Canada ITSP-10-171 2025 | 03.13.01.A 03.14.06.C |
Capability Maturity Model
Level 0 — Not Performed
Practices are non-existent, based on the inability to demonstrate an implemented and operational capability. A reasonable person would conclude the control is not being performed.
Level 1 — Performed Informally
Continuous Monitoring (MON) domain capabilities are ad hoc and inconsistent. Capability criteria associated with this control may include: ▪ Policies, standards & procedures associated with MON domain capabilities provide limited coverage due to the depth and breadth of the existing documentation. ▪ Event monitoring-related activities are decentralized (e.g., a localized/regionalized function) and uses non-standardized methods to implement secure, resilient and compliant practices. ▪ Monitoring is primarily reactive in nature, focused on identifying incidents that occurred. ▪ Event log reviews primarily rely on manual processes to identify anomalous behaviors. ▪ Generating event logs and the review of those event logs is narrowly-focused to business-critical Technology Assets, Applications, Services and/or Data (TAASD).
Level 2 — Planned & Tracked
Continuous Monitoring (MON) capabilities are requirements-driven, but are not standardized across the entity (e.g., local/regional level consistency). Capability criteria associated with this control reasonably expect the following criteria to exist: ▪ Policies and standards associated with MON domain capabilities are formally documented and centrally-managed by the entity. ▪ Standardized Operating Procedures (SOP) associated with MON domain capabilities are documented and maintained by process owners. ▪ IT and/or cybersecurity personnel work with business stakeholders and process owners to appropriately scope and reasonably implement cybersecurity and data protection controls associated with MON domain capabilities to address applicable statutory, regulatory and/or contractual requirements for Technology Assets, Applications, Services and/or Data (TAASD). ▪ Continuous monitoring-related controls are primarily administrative and preventative in nature (e.g., policies, standards and procedures & guidelines). ▪ Continuous monitoring may be a defined function (e.g., team or department) or assigned as an additional duty to existing IT and/or cybersecurity personnel.
Level 3 — Well Defined
Continuous Monitoring (MON) capabilities are standardized across the entity for applicability to People, Processes, Technologies, Data and/or Facilities (PPTDF) to ensure consistency for Technology Assets, Applications, Services and/or Data (TAASD). Capability criteria associated with this control reasonably expect the following criteria to exist: ▪ Policies and standards associated with MON domain capabilities are formally documented and centrally-managed by the entity's Governance, Risk & Compliance (GRC) team, or similar function. ▪ Cybersecurity personnel use a structured process via Standardized Operating Procedures (SOP) to review and analyze logs. ▪ A Security Operations Center (SOC) team, or similar function, is appropriately staffed and supported to implement and maintain MON domain capabilities. ▪ Technology is leveraged to enhance the efficiency and accuracy of continuous monitoring operations (e.g., Security Incident Event Manager (SIEM)). ▪ The entity's Governance, Risk & Compliance (GRC) team, or similar function, works with business stakeholders and process owners to appropriately scope and reasonably implement cybersecurity and data protection controls associated with MON domain capabilities to address Minimum Compliance Requirements (MCR) (e.g., applicable statutory, regulatory and/or contractual requirements) and Discretionary Security Requirements (DSR) (e.g., entity-required controls). ▪ Secure Baseline Configurations (SBC) enforce security event logging to contain sufficient information to establish necessary details of activity and allow for forensics analysis. ▪ An implemented and operational capability exists to continuously monitor inbound and outbound communications traffic for unusual or unauthorized activities or conditions.
Level 4 — Quantitatively Controlled
Utilize SCR-CMM Level 3 criteria definitions: ▪ There are no defined Level 4 criteria, since it is reasonable to assume a quantitatively-controlled process is not necessary to operationalize this control. ▪ While it may be possible to develop “metrics-driven” capabilities for this control, the criteria would be organization-specific to define.
Level 5 — Continuously Improving
Utilize SCR-CMM Level 3 or Level 4 (if available) criteria definitions: ▪ There are no defined Level 5 criteria, since it is reasonable to assume a continuously-improving process is not necessary to operationalize this control. ▪ Level 5 capabilities should be considered “world-class” where the control builds on Level 4 capabilities, but are continuously improving through Artificial Intelligence (AI) and/or Machine Learning (ML) technologies. ▪ While it may be possible to develop responsive capabilities for this control through the use of AI and/or ML technologies, the criteria would be organization-specific to define.
Assessment Objectives
- MON-22_A01 criteria for unusual or unauthorized activities or conditions for inbound communications traffic are defined.
- MON-22_A02 criteria for unusual or unauthorized activities or conditions for outbound communications traffic are defined.
- MON-22_A03 unusual or unauthorized activities or conditions that are to be monitored in outbound communications traffic are defined.
- MON-22_A04 inbound communications traffic is monitored to detect unusual or unauthorized activities or conditions.
- MON-22_A05 outbound communications traffic is monitored to detect unusual or unauthorized activities or conditions.
- MON-22_A06 anomalous or suspicious behavior is defined.
- MON-22_A07 systems, applications and services are monitored to detect attacks and indicators of potential attacks.
- MON-22_A08 communications at external managed interfaces to the system are monitored.
- MON-22_A09 communications at key internal managed interfaces within the system are monitored.
- MON-22_A10 the frequency at which to monitor inbound communications traffic for unusual or unauthorized activities or conditions is defined.
Evidence Requirements
- E-NET-11 Intrusion Detection / Prevention Deployment
-
Documented evidence of Network and Host Intrusion Detection / Prevention Systems (NIDS / NIPS, HIDS / HIPS) deployment and monitoring coverage.
Network Security
Technology Recommendations
Micro/Small
- Intrusion Detection / Prevention Systems (IDS / IPS)
Small
- Intrusion Detection / Prevention Systems (IDS / IPS)
Medium
- Intrusion Detection / Prevention Systems (IDS / IPS)
- Extended Detection and Response (XDR)
Large
- Intrusion Detection / Prevention Systems (IDS / IPS)
- Extended Detection and Response (XDR)
Enterprise
- Intrusion Detection / Prevention Systems (IDS / IPS)
- Extended Detection and Response (XDR)