Hosting (HST)

What the layer describes

The HST layer answers the question “Who hosts it, and where?”. It describes hosting, physical or cloud, with its providers (HostingProvider), data centres (DataCentre), cloud regions (CloudRegion) and contracts (HostingContract). The layer also keeps sites, rooms, racks and equipment capacity (PhysicalEquipment).

Concepts and how they relate

Of the elements that run or store software, only five types link to their place, where needed, through the “is hosted by” relationship (hostedBy). From RUN, these are clusters (Cluster), nodes (Node) and managed services (ManagedService). From APP, these are software systems (SoftwareSystem) and data stores (DataStore).

The target of the relationship is a data centre, a cloud region or a hosting provider. Where needed, the data centre and the cloud region are hosted by their provider, through the same relationship. In this way the model shows the hosting chain, from the runtime node to the provider.

A data centre belongs to the location family. For that reason it may compose physical locations (PhysicalLocation), such as rooms and racks, and physical equipment. The relationship is “composes” (composition).

Element types

The layer has 6 element types, in these families: structure (2), information (1), location (3). Each type's own fields are listed under its definition; the fields common to every element are described under the core concepts.

• HostingProviderHosting provider · structure family

  An organisation supplying hosting capacity or services.

  Key attributes: kindjurisdictioncertifications
• DataCentreData centre · location family

  A hosting facility containing physical infrastructure.

  Key attributes: countrytier
• CloudRegionCloud region · location family

  A geographic hosting region offered by a cloud provider.

  Key attributes: countryavailabilityZones
• HostingContractHosting contract · information family

  An agreement for hosting services or capacity.

  Key attributes: slastartsOnendsOn
• PhysicalEquipmentPhysical equipment · structure family

  Physical computing or networking equipment in a hosting context.

  Key attributes:
• PhysicalLocationPhysical location · location family

  A physical site, room, rack or other location containing equipment.

  Key attributes: regionhorizonProfilekindparentLocationcodecountrylocalityaddressoperatorNameexternalReferencesiteRolecapacityU

In the “Family support benefit” example

Figure 4.8 (page 36) shows the HST layer in the example. The node “Benefits runtime node”, from RUN, is hosted by the data centre “Primary data centre”. In turn, the data centre is hosted by the provider “Government hosting provider”. The provider is a government body, and its hosting type is governmentCloud.