Key Trust Boundaries

Table 5-1 Key Trust Boundaries

Trust Boundary	Contains	Access Control
Site Trust Boundary	All the NF and other supporting elements for a given site.	Cluster Access Policies are implemented using some kind of Access Control Group (or Security Group) mechanism.
Cluster Trust Boundary	All the Compute Elements for a given cluster	Network Policies controls traffic ingress and egress; Pod Security Policies controls the kinds of workloads allowed in the cluster (e.g., no pods requiring privilege escalation).
DB Trust Boundary	All the DB Tier Elements for a given Cluster	Firewall Policies control traffic ingress and egress; DB grants and other permission mechanisms provide authorization for authorized users.
Orchestrator Trust Boundary	The orchestration interface and keys	Firewall Policies control access to a Bastion server which provides orchestration services; access to the Bastion host uses SSH. The cluster orchestration keys are stored on the Bastion host.
CS Trust Boundary	The common services implementing logging, tracing, and measurements.	Each of the common services provides independent user interfaces (GUIs) that are currently open. The customer may want to introduce an api-gateway and implement authentication and authorization mechanisms to protect the OAM data. The common services may be configured to use Trasport Layer Security (TLS); when TLS is used, certificates will need to be generated and deployed via the orchestrator.
NF Trust Boundaries	A collection of one (or more) 5G Network Functions deployed as a service.	Some 5G NF microservices provide OAM access via a GUI. 5G NF microservices provide Signaling access via a TLS protected HTTP2 interface. The certificates for these interfaces are managed via the certificate manager.