Identity, but Also Isolated by VLAN Network Overview: Tenant Isolation in Storage Area Network Ceph is a widely used, multi-tenant, high-throughut, distributed storage system. It provides logical isolation through identity-based authentication and authorization. However, all client and server nodes still share a single public Storage Area Network. To achieve defense-in-depth, we developed Secure Ceph, which locks down RADOS connections by partitioning the Layer-3 public network among tenants using VLANs. Each tenant’s clients are confined to a dedicated VLAN, whereas servers asymmetrically aggregate and flatten multiple VLANs into a single unified Layer-3 space—without exposing tenants to each other. We term this asymmetric design L3 lockdown. This network-level isolation also strengthens authentication by validating requests against their VLAN origin. Secure Ceph thereby enables confidentiality-sensitive workloads in one’s own isolated storage pool. https://SecureCeph.Github.io/