What feature does OCI provide to isolate network traffic between different tenants?

The feature that OCI provides to isolate network traffic between different tenants is the Virtual Cloud Network (VCN) with security lists and network security groups.

A Virtual Cloud Network is a private network hosted within the Oracle Cloud Infrastructure, allowing users to segment their resources to ensure that traffic remains isolated from other tenants. VCNs enable the creation of subnets, routing tables, and gateways, effectively controlling the flow of traffic in and out of the network.

Security lists act as virtual firewalls for the subnets within the VCN, allowing for highly granular control over ingress and egress traffic at the subnet level. On the other hand, network security groups provide an additional layer of security by allowing users to group resources and apply security rules collectively. This dual approach allows for sophisticated network segmentation and enhanced security, making it difficult for other tenants to access or interfere with your traffic.

While Virtual Private Cloud, shared networks with encryption, and public cloud settings may offer some level of isolation, they do not provide the same fine-grained control and tenant separation that VCNs combined with security lists and network security groups do, making them less effective for isolating network traffic between different tenants.