Skip to main content

NET-05: Interconnection Security Agreements (ISAs)

NET 9 — Critical Protect

Mechanisms exist to authorize connections from systems to other systems using Interconnection Security Agreements (ISAs), or similar methods, that document, for each interconnection, the interface characteristics, cybersecurity and data protection requirements and the nature of the information communicated.

Control Question: Does the organization authorize connections from systems to other systems using Interconnection Security Agreements (ISAs), or similar methods, that document, for each interconnection, the interface characteristics, cybersecurity and data protection requirements and the nature of the information communicated?

General (27)
Framework Mapping Values
GovRAMP Low CA-03
GovRAMP Low+ CA-03
GovRAMP Moderate CA-03
GovRAMP High CA-03
MITRE ATT&CK 10 T1020.001, T1041, T1048, T1048.002, T1048.003, T1567
NIST 800-53 R4 CA-3 CA-3(1) CA-3(2)
NIST 800-53 R4 (low) CA-3
NIST 800-53 R4 (moderate) CA-3
NIST 800-53 R4 (high) CA-3
NIST 800-53 R5 (source) CA-3 SC-7(25) SC-7(26)
NIST 800-53B R5 (low) (source) CA-3
NIST 800-53B R5 (moderate) (source) CA-3
NIST 800-53B R5 (high) (source) CA-3
NIST 800-53 R5 (NOC) (source) SC-7(25) SC-7(26)
NIST 800-82 R3 LOW OT Overlay CA-3
NIST 800-82 R3 MODERATE OT Overlay CA-3
NIST 800-82 R3 HIGH OT Overlay CA-3
NIST 800-161 R1 CA-3
NIST 800-161 R1 C-SCRM Baseline CA-3
NIST 800-161 R1 Flow Down CA-3
NIST 800-161 R1 Level 3 CA-3
NIST 800-171 R2 (source) NFO-CA-3
NIST 800-171 R3 (source) 03.01.03 03.01.20.c.02 03.12.05.a 03.12.05.b
NIST 800-171A R3 (source) A.03.01.03[02] A.03.12.05.ODP[01] A.03.12.05.ODP[02] A.03.12.05.a[01] A.03.12.05.a[02] A.03.12.05.b[01] A.03.12.05.b[02] A.03.12.05.b[03] A.03.12.05.c[01] A.03.12.05.c[02]
SCF CORE ESP Level 1 Foundational NET-05
SCF CORE ESP Level 2 Critical Infrastructure NET-05
SCF CORE ESP Level 3 Advanced Threats NET-05
US (18)
EMEA (2)
Framework Mapping Values
EMEA Germany C5 2020 COS-03
EMEA Israel CDMO 1.0 16.4
Americas (1)
Framework Mapping Values
Americas Canada ITSP-10-171 03.01.03 03.01.20.C.02 03.12.05.A 03.12.05.B

Capability Maturity Model

Level 0 — Not Performed

There is no evidence of a capability to authorize connections from systems to other systems using Interconnection Security Agreements (ISAs), or similar methods, that document, for each interconnection, the interface characteristics, cybersecurity and data protection requirements and the nature of the information communicated.

Level 1 — Performed Informally

C|P-CMM1 is N/A, since a structured process is required to authorize connections from systems to other systems using Interconnection Security Agreements (ISAs) that document, for each interconnection, the interface characteristics, cybersecurity and data protection requirements and the nature of the information communicated.

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

See C|P-CMM3. There are no defined C|P-CMM4 criteria, since it is reasonable to assume a quantitatively-controlled process is not necessary to authorize connections from systems to other systems using Interconnection Security Agreements (ISAs), or similar methods, that document, for each interconnection, the interface characteristics, cybersecurity and data protection requirements and the nature of the information communicated.

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 authorize connections from systems to other systems using Interconnection Security Agreements (ISAs), or similar methods, that document, for each interconnection, the interface characteristics, cybersecurity and data protection requirements and the nature of the information communicated.

Assessment Objectives

  1. NET-05_A01 the type of agreement used to approve and manage the exchange of information is defined (e.g., interconnection security agreements, information exchange security agreements, memoranda of understanding or agreement, service level agreements, user agreements, non-disclosure agreements or organization-defined type of agreements).
  2. NET-05_A02 security requirements for each system are documented as part of the exchange agreements.
  3. NET-05_A03 controls are documented as part of each exchange agreement.
  4. NET-05_A04 the frequency at which to review and update agreements is defined.
  5. NET-05_A05 the exchange of sensitive / regulated data between the system and other systems is approved using organization-defined values.
  6. NET-05_A06 the exchange of sensitive / regulated data between the system and other systems is managed using organization-defined values.
  7. NET-05_A07 interface characteristics for each system are documented as part of the exchange agreements.
  8. NET-05_A08 responsibilities for each system are documented as part of the exchange agreements.
  9. NET-05_A09 the impact level of the information communicated is documented as part of each exchange agreement.
  10. NET-05_A10 exchange agreements are reviewed per an organization-defined frequency.
  11. NET-05_A11 exchange agreements are updated per an organization-defined frequency.
  12. NET-05_A12 systems are prohibited from directly connecting to an external network is defined.
  13. NET-05_A13 the boundary protection device required for a direct connection to an external network is defined.
  14. NET-05_A14 the direct connection of systems to an external network without the use of boundary protection device is prohibited.
  15. NET-05_A15 the direct connection of classified national security system to an external network without the use of an organization-defined boundary protection device is prohibited.
  16. NET-05_A16 approved authorizations are enforced for controlling the flow of CUI between connected systems.
  17. NET-05_A17 one or more of the following PARAMETER VALUES are selected: {interconnection security agreements; information exchange security agreements; memoranda of understanding or agreement; service-level agreements; user agreements; non-disclosure agreements; other types of agreements}.
  18. NET-05_A18 the exchange of CUI between the system and other systems is approved using <A.03.12.05.ODP[01]: SELECTED PARAMETER VALUES>.
  19. NET-05_A19 the exchange of CUI between the system and other systems is managed using <A.03.12.05.ODP[01]: SELECTED PARAMETER VALUES>.
  20. NET-05_A20 exchange agreements are reviewed <A.03.12.05.ODP[02]: frequency>.
  21. NET-05_A21 exchange agreements are updated <A.03.12.05.ODP[02]: frequency>.

Evidence Requirements

E-NET-06 Authorized Network Connections

Documented evidence of systems, applications and/or services authorized to connect to organizational systems, including remote access authorizations.

Network Security

Technology Recommendations

Micro/Small

  • Interconnection Security Agreement (ISA)
  • Information Exchange Security Agreements (IESA)
  • Memoranda of Understanding (MOU) / Agreement (MOA)

Small

  • Interconnection Security Agreement (ISA)
  • Information Exchange Security Agreements (IESA)
  • Memoranda of Understanding (MOU) / Agreement (MOA)

Medium

  • Interconnection Security Agreement (ISA)
  • Information Exchange Security Agreements (IESA)
  • Memoranda of Understanding (MOU) / Agreement (MOA)

Large

  • Interconnection Security Agreement (ISA)
  • Information Exchange Security Agreements (IESA)
  • Memoranda of Understanding (MOU) / Agreement (MOA)

Enterprise

  • Interconnection Security Agreement (ISA)
  • Information Exchange Security Agreements (IESA)
  • Memoranda of Understanding (MOU) / Agreement (MOA)

The Secure Controls Framework (SCF) is maintained by SCF Council. Use of SCF content is subject to the SCF Terms & Conditions.

Manage this control in SCF Connect

Track implementation status, collect evidence, and map controls to your compliance frameworks automatically.