Retrofit Adoption
Compliance frameworks vary greatly. Within a framework, the granularity of required information can also vary from one organization to the next.
OSCAL is designed to normalizes the variability between frameworks. It also offers flexibility to handle information at varying levels of granularity. As a result, representing content in OSCAL can be ambiguous to early adoptors.
As with any technology project, OSCAL adoption should start with the minimum viable product (MVP) and evolve to more comprehensive use cases.
SSP Adoption Overview
The OSCAL Foundation recommends the following addoption path for FedRAMP SSP creation.
MinimumToViable Product (MVP): Simplefacilitate conversion ofcontrolslegacyandWordinentory.content,MinimumOSCALnecessaryallowsfront-matter.Intermediate: Begin including required attachments and additional front-matter.Advanced: Include most remaining SSP topics, convert inventory to usecomponents.Ideal: Include remaining SSP topics that rely heavily on the use of components. Begin convertinglegacy control responses toalign with relevant components.-
Minimum Front-Matter and OSCAL-required Content.
metadataincludes:title,published,last-modified,version,oscal-versionroles: CSP, ISSO, others as cited in controlsparties: the CSPresponsible-party: exactly one, linking the CSP party to the CSP role
system-characteristicsincludes:system-id,system-name,system-name-short,description- cloud-service-model
propand cloud-deployment-modelprop security-sensitivity-level(fips-199-high,fips-199-moderate,fips-199-low)system-information: exactly one entry with Appendix K pasted into thedescriptionstatus: Required field. Use as-isauthorization-boundary:descriptionandlinksentry identifying the external attachment.network-architecture:descriptionandlinksentry identifying the external attachment.data-flow:descriptionandlinksentry identifying the external attachment.
system-implementationincludes:users: Required by OSCAL, but no longer required by FedRAMP.Singleauthorized-privilegesentry with emptytitleandfunction-performed` set to "none"
- this-system
componentsentry
-
Convert controls without modification, with all response statements in the "this-system" component.
control-implementationimplemented-requirement(AC-1, AC-2, etc.)set-parameters: set parameters as neededstatement(part a, part b, etc.by-component("this system")description: Content directly from legacy Word SSP (part a, part b, etc.)implementation-statusresponsible-roles: One entry per role. Userole-id. Must matchmetadata/roles/id.
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Flat Inventory, converted directly from spreadsheet. No corrisponding components.
system-implementation:inventory-items: All inventory converted from Excel spreadsheet
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Required attachments
- Add direct
linksfrom the appropriate controls to identify relevant attachments
- Add direct
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Required SSP roles
metadata/rolesThe roles required by SSP (System owner, ISSO, AO, etc.)metada/parties: the people, teams and organizations responsible for the above rolesmetadata/responsible-parties: links the aboverolesandparties
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Information types
system-characteristics/system-information/information-types- a single entry for each row in appendix K.
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leveraged authorizations
system-implementation/leveraged-authorizations:- one entry for leveraged authorization
- corrisponding
metadata/partiesentry for each - corrisponding
system-implementation/componentsfor each.
-
Separation of Duties Matrix
system-implementation/users- one entry per row in Table 11.1
./authorized-privilege/functions-performed: SSP Table 11.1 Duty Description (just one entry in the array)./authorized-privilege/title: Required by OSCAL, not by FedRAMP. Recommend duplicating thefunctions-performedcontent.role-ids: linksmetadata/rolestofunctions-performed
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Customer Responsibility and Inheritance:
- Move customer responsibility statements to
//by-components/export/responsibilities
- Move customer responsibility statements to
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Normalize Inventory: Transition flat inventory to component-based inventory.
- Use
componentsto the greatest degree practical inventory-itemsbecome implemented instances of components
- Use
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external systems and services
system-implementation/componentsentries for each
-
Transition to
resources- Where practical,
linksentries use URI fragments to reference resources instead of direct links.
- Where practical,
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Components for Required Documents
- policy
componentsentries for each required policy - process-procedure
componentsentries for each required process - plan
componentsentries for each required plan - _useradd components for policies, processes, plans and other documents
- policy
-
Services, Ports and Protocols
-
Cryptographic Modules (App Q table)
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Migrateto component-based control responses
- Add
by-componentsentries toimplemented-requirementsfor each relevant component - Add/move component-specific control responses to their associated
by-componentsresponse. - Migrate slowly over time.
- Add
See details below.
