Out-of-band Channels
LOW MODERATE HIGHRequirements NIST SOURCE
Employ the following out-of-band channels for the physical delivery or electronic transmission of [information, system components, or devices] to [individuals or systems]: [out-of-band channels].
Discussion (NIST Supplemental Guidance)
Out-of-band channels include local, non-network accesses to systems; network paths physically separate from network paths used for operational traffic; or non-electronic paths, such as the U.S. Postal Service. The use of out-of-band channels is contrasted with the use of in-band channels (i.e., the same channels) that carry routine operational traffic. Out-of-band channels do not have the same vulnerability or exposure as in-band channels. Therefore, the confidentiality, integrity, or availability compromises of in-band channels will not compromise or adversely affect the out-of-band channels. Organizations may employ out-of-band channels in the delivery or transmission of organizational items, including authenticators and credentials; cryptographic key management information; system and data backups; configuration management changes for hardware, firmware, or software; security updates; maintenance information; and malicious code protection updates. For example, cryptographic keys for encrypted files are delivered using a different channel than the file.
Enhancements NIST SOURCE
SC-37(1) Ensure Delivery and Transmission LOW MODERATE HIGH
Employ [controls] to ensure that only [individuals or systems] receive the following information, system components, or devices: [information, system components, or devices].
Discussion
Techniques employed by organizations to ensure that only designated systems or individuals receive certain information, system components, or devices include sending authenticators via an approved courier service but requiring recipients to show some form of government-issued photographic identification as a condition of receipt.
Implementation Guidance
Original engineering commentary written for this explorer — not NIST source text and not authoritative guidance.
No engineering interpretation has been authored for SC-37 yet. This section is architected to receive it — see the Requirements and Assessment sections above for the authoritative NIST source content in the meantime.
Assessment
Assessment Objectives
- out-of-band channels to be employed for the physical delivery or electronic transmission of information, system components, or devices to individuals or the system are defined;
- information, system components, or devices to employ out-of-band-channels for physical delivery or electronic transmission are defined;
- individuals or systems to which physical delivery or electronic transmission of information, system components, or devices is to be achieved via the employment of out-of-band channels are defined;
- <SC-37_ODP[01] out-of-band channels> are employed for the physical delivery or electronic transmission of <SC-37_ODP[02] information, system components, or devices> to <SC-37_ODP[03] individuals or systems>.
Examine
[SELECT FROM: System and communications protection policy; procedures addressing the use of out-of-band channels; access control policy and procedures; identification and authentication policy and procedures; system design documentation; system architecture; system configuration settings and associated documentation; list of out-of-band channels; types of information, system components, or devices requiring the use of out-of-band channels for physical delivery or electronic transmission to authorized individuals or systems; physical delivery records; electronic transmission records; system audit records; system security plan; other relevant documents or records].
Interview
[SELECT FROM: System/network administrators; organizational personnel with information security responsibilities; organizational personnel installing, configuring, and/or maintaining the system; organizational personnel authorizing, installing, configuring, operating, and/or using out-of-band channels; system developers/integrators].
Test
[SELECT FROM: Organizational processes for the use of out-of-band channels; mechanisms supporting and/or implementing the use of out-of-band channels].
STIGs & CCIs
No STIG checks or CCI mappings are currently loaded for SC-37. This section is architected to display, per product: STIG ID, Finding ID, Severity, Title, Description, Check, Fix, CCI, and NIST control mapping — but nothing is populated here until a real DISA STIG/CCI dataset is ingested.
Learn more about STIG/CCI integration →Evidence
Categorized from the SP 800-53A "Examine"/"Test" artifact list above by keyword — not an authoritative NIST evidence list.
Policy
- System and communications protection policy
- access control policy and procedures
- identification and authentication policy and procedures
- system security plan
Configuration
- system design documentation
- system architecture
- system configuration settings and associated documentation
Testing
- Organizational processes for the use of out-of-band channels
- mechanisms supporting and/or implementing the use of out-of-band channels
Other Records
- procedures addressing the use of out-of-band channels
- list of out-of-band channels
- types of information, system components, or devices requiring the use of out-of-band channels for physical delivery or electronic transmission to authorized individuals or systems
- physical delivery records
- electronic transmission records
- system audit records
- other relevant documents or records