Glossary
bwIDM: Federated identity management system of the higher education institutions in Baden-Württemberg, Germany (https://www.bwidm.de).
bwSupportPortal: Federated support portal in Baden-Württemberg for services such as bwCloud-OS, bwHPC, and bwSFS (https://bw-support.scc.kit.edu).
Flavor: Predefined resource profile for instances (number of vCPUs, RAM, and local system disk). Examples: m1.small, m1.large.
Floating IP: Publicly accessible IP address that can be assigned to an instance as needed. This keeps the internal network topology unchanged.
Home Region: The region automatically assigned to a user during registration.
IaaS (Infrastructure as a Service): A cloud computing service model in which computing resources are provided by a cloud service provider. The provider supplies the storage, networking, servers, and virtualization.
Image: Operating system image from which new instances are launched. bwCloud-OS provides various preconfigured images (e.g., Debian 12, Ubuntu 24.04); custom images can also be uploaded.
Instance / VM: Virtual machine running in a region. It receives CPU, RAM, network, and storage resources, and behaves like a physical server.
Project / Group Project: Administrative container for resources, users, and quotas. In a group project, multiple people share all instances, images, security groups, etc. equally.
Quota: Resource limits (vCPUs, RAM, volumes, etc.) per project. Increases can be requested via a support ticket.
Region: One of the four operational sites (Freiburg, Karlsruhe, Mannheim, Ulm). Each region is an independent OpenStack cluster with its own IP address logic.
Security Group: Set of firewall rules (inbound/outbound) assigned to an instance. By default, only SSH (port 22) is open. Additional ports must be explicitly allowed.
Snapshot: Point-in-time copy of an instance or volume. Snapshots appear as images and can be downloaded or used to create new volumes or instances.
Volume (Block Storage): Persistent storage in bwCloud-OS that exists independently of a VM. Volumes can be attached to instances, resized, exported as images, and backed up via snapshots.