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NET-03.2: External Telecommunications Services

NET 7 — High Protect

Mechanisms exist to maintain a managed interface for each external telecommunication service that protects the confidentiality and integrity of the information being transmitted across each interface.

Control Question: Does the organization maintain a managed interface for each external telecommunication service that protects the confidentiality and integrity of the information being transmitted across each interface?

General (13)
US (9)
Framework Mapping Values
US CMS MARS-E 2.0 SC-7(4)
US FedRAMP R4 SC-7(4)
US FedRAMP R4 (moderate) SC-7(4)
US FedRAMP R4 (high) SC-7(4)
US FedRAMP R5 (source) SC-7(4)
US FedRAMP R5 (moderate) (source) SC-7(4)
US FedRAMP R5 (high) (source) SC-7(4)
US IRS 1075 SC-7(4) SC-7(9)
US - TX TX-RAMP Level 2 SC-7(4)
EMEA (2)
Framework Mapping Values
EMEA Germany C5 2020 COS-03
EMEA Israel CDMO 1.0 9.5
APAC (1)
Framework Mapping Values
APAC Australia ISM June 2024 ISM-0546 ISM-1562

Capability Maturity Model

Level 0 — Not Performed

There is no evidence of a capability to maintain a managed interface for each external telecommunication service that protects the confidentiality and integrity of the information being transmitted across each interface.

Level 1 — Performed Informally

Network Security (NET) efforts are ad hoc and inconsistent. CMM Level 1 control maturity would reasonably expect all, or at least most, the following criteria to exist:

  • IT personnel use an informal process to design, build and maintain secure networks for test, development, staging and production environments, including the implementation of appropriate cybersecurity and data protection controls.
  • Administrative processes are used to configure boundary devices (e.g., firewalls, routers, etc.) to deny network traffic by default and allow network traffic by exception (e.g., deny all, permit by exception).
  • Network monitoring is primarily reactive in nature.
Level 2 — Planned & Tracked

Network Security (NET) efforts are requirements-driven and governed at a local/regional level, but are not consistent across the organization. CMM Level 2 control maturity would reasonably expect all, or at least most, the following criteria to exist:

  • Network security management is decentralized (e.g., a localized/regionalized function) and uses non-standardized methods to implement secure, resilient and compliant practices.
  • IT/cybersecurity personnel identify cybersecurity and data protection controls that are appropriate to address applicable statutory, regulatory and contractual requirements for network security management.
  • IT personnel define secure networking practices to protect the confidentiality, integrity, availability and safety of the organization's technology assets, data and network(s).
  • Administrative processes and technologies focus on protecting High Value Assets (HVAs), including environments where sensitive/regulated data is stored, transmitted and processed.
  • Administrative processes are used to configure boundary devices (e.g., firewalls, routers, etc.) to deny network traffic by default and allow network traffic by exception (e.g., deny all, permit by exception).
  • Network segmentation exists to implement separate network addresses (e.g., different subnets) to connect systems in different security domains (e.g., sensitive/regulated data environments).
Level 3 — Well Defined

Network Security (NET) efforts are standardized across the organization and centrally managed, where technically feasible, to ensure consistency. CMM Level 3 control maturity would reasonably expect all, or at least most, the following criteria to exist:

  • A Technology Infrastructure team, or similar function, defines centrally-managed network security controls for implementation across the enterprise.
  • Secure engineering principles are used to design and implement network security controls (e.g., industry-recognized secure practices) to enforce the concepts of least privilege and least functionality at the network level.
  • IT/cybersecurity architects work with the Technology Infrastructure team to implement a “layered defense” network architecture that provides a defense-in-depth approach for redundancy and risk reduction for network-based security controls, including wired and wireless networking.
  • Administrative processes and technologies configure boundary devices (e.g., firewalls, routers, etc.) to deny network traffic by default and allow network traffic by exception (e.g., deny all, permit by exception).
  • Technologies automate the Access Control Lists (ACLs) and similar rulesets review process to identify security issues and/ or misconfigurations.
  • Network segmentation exists to implement separate network addresses (e.g., different subnets) to connect systems in different security domains (e.g., sensitive/regulated data environments).
Level 4 — Quantitatively Controlled

Network Security (NET) efforts are metrics driven and provide sufficient management insight (based on a quantitative understanding of process capabilities) to predict optimal performance, ensure continued operations and identify areas for improvement. In addition to CMM Level 3 criteria, CMM Level 4 control maturity would reasonably expect all, or at least most, the following criteria to exist:

  • Metrics reporting includes quantitative analysis of Key Performance Indicators (KPIs).
  • Metrics reporting includes quantitative analysis of Key Risk Indicators (KRIs).
  • Scope of metrics, KPIs and KRIs covers organization-wide cybersecurity and data protection controls, including functions performed by third-parties.
  • Organizational leadership maintains a formal process to objectively review and respond to metrics, KPIs and KRIs (e.g., monthly or quarterly review).
  • Based on metrics analysis, process improvement recommendations are submitted for review and are handled in accordance with change control processes.
  • Both business and technical stakeholders are involved in reviewing and approving proposed changes.
Level 5 — Continuously Improving

See C|P-CMM4. There are no defined C|P-CMM5 criteria, since it is reasonable to assume a continuously-improving process is not necessary to maintain a managed interface for each external telecommunication service that protects the confidentiality and integrity of the information being transmitted across each interface.

Assessment Objectives

  1. NET-03.2_A01 the frequency at which to review exceptions to traffic flow policy is defined.
  2. NET-03.2_A02 a managed interface is implemented for each external telecommunication service.
  3. NET-03.2_A03 a traffic flow policy is established for each managed interface.
  4. NET-03.2_A04 the confidentiality of the information being transmitted across each interface is protected.
  5. NET-03.2_A05 the integrity of the information being transmitted across each interface is protected.
  6. NET-03.2_A06 each exception to the traffic flow policy is documented with a supporting mission or business need and duration of that need.
  7. NET-03.2_A07 exceptions to the traffic flow policy are reviewed frequently.
  8. NET-03.2_A08 exceptions to the traffic flow policy that are no longer supported by an explicit mission or business need are removed.
  9. NET-03.2_A09 unauthorized exchanges of control plan traffic with external networks are prevented.
  10. NET-03.2_A10 information is published to enable remote networks to detect unauthorized control plane traffic from internal networks.
  11. NET-03.2_A11 unauthorized control plane traffic is filtered from external networks.
  12. NET-03.2_A12 outgoing communications traffic posing a threat to external systems is detected.
  13. NET-03.2_A13 outgoing communications traffic posing a threat to external systems is denied.
  14. NET-03.2_A14 the identity of internal users associated with denied communications is audited.

Technology Recommendations

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