+The nearly complete data model for CAPIF is shown in the diagram below.
+
+<img src="docs/diagrams/Information model for CAPIF.svg">
+
+The data used within CAPIF Core for registering rApps that provide and consume services is shown in the diagram below.
+
+<img src="docs/diagrams/Information in rApp registration.svg">
+
+Some examples of interactions between components using the CAPIF interface are shown in the sequence diagram below.
+
+***NOTE!*** It has not been decided that CAPIF Core will actually handle the Helm chart installation. The prototype includes this as an example of what CAPIF Core could potentially do.
+
+<img src="docs/diagrams/Register Provider.svg">
+
+If Helm is used, before publishing a service, the chart belonging to the service must be registered in ChartMuseum. When publishing the service the following information should be provided in the `ServiceAPIDescription::description` attribute; "namespace", "repoName", "chartName", "releaseName". An example of the information: "Description of rApp helloWorld,namespace,repoName,chartName,releaseName".
+
+## Generation of API code
+
+The CAPIF APIs are generated from the OpenAPI specifications provided by 3GPP. The `generate.sh` script downloads the
+specifications from 3GPP, fixes them and then generates the APIs. It also generates the mocks needed for unit testing.
+The specifications are downloaded from the following site; https://www.3gpp.org/ftp/Specs/archive/29_series. To see
+the APIs in swagger format, see the following link; https://github.com/jdegre/5GC_APIs/tree/Rel-16#common-api-framework-capif.
+**NOTE!** The documentation in this link is for release 16 of CAPIF, the downloaded specifications are for release 17.
+
+To fix the specifications there are three tools:
+- `commoncollector`, collects type definitions from peripheral specifications to keep down the number of dependencies to
+ other specifications. The types to collect are listed in the `definitions.txt`file. Some fixes are hard coded.
+- `enumfixer`, fixes enumeration definitions so they can be properly generated.
+- `specificationfixer`, fixes flaws in the specifications so they can be properly generated. All fixes are hard coded.
+
+### Steps to add a new dependency to the commoncollector
+
+When a dependency to a new specification is introduced in any of the CAPIF specifications, see example below, the following steps should be performed:
+
+For the CAPIF specification "TS29222_CAPIF_Discover_Service_API" a new dependency like the following has been introduced.
+
+ websockNotifConfig:
+ $ref: ✅TS29122_CommonData.yaml#/components/schemas/WebsockNotifConfig✅'
+
+1. Copy the part between the checkboxes of the reference and add it to the `definitions.txt` file. This step is not needed if the type is already defined in the file.
+2. Look in the `generate.sh` script, between the "<replacements_start>" and "<new_replacement>" tags, to see if "TS29122_CommonData"
+ has already been replaced in "TS29222_CAPIF_Discover_Service_API".
+3. If it has not been replaced, add a replacement above the "<new_replacement>" tag by copying and adapting the two rows above the tag.
+
+### Security in CAPIF
+
+The security requirements applicable to all CAPIF entities include providing an authorization mechanism for service APIs from third-party API providers and supporting a common security mechanism for all API implementations to ensure confidentiality and integrity protection.
+
+In the current implementation Keycloak is being used as identity and access management (IAM) solution that provides authentication, authorization, and user management for applications and services. Keycloak provides robust authentication mechanisms, including username/password, two-factor authentication, and client certificate authentication that complies with CAPIF security requirements.