Page 300 - Cloud computing: From paradigm to operation

1 Framework and requirements for cloud computing

Secondary
cloud service
provider
Catalogue of
service offerings

Primary
cloud
service
provider
Catalogue of
service offerings

CSC 1 CSC 2 CSC 3

Cloud service customers
Y.3511(14)_F8-8

Figure 8-8 – Services provided from a secondary CSP to a primary CSP

The primary CSP may offer services from multiple secondary CSPs. Some of the services offered by the
secondary CSPs may themselves be their own services or services from other CSPs. Note that the roles of
primary and secondary service providers may change depending on the service under consideration.
The primary CSP serving the CSC provides the service level agreement (SLA) to the CSC and is responsible for
ensuring that both services hosted by that primary CSP and services offered from a secondary CSP will meet
the SLA between the CSC and the primary CSP.
8.3.3 Network connectivity

In considering network connectivity for the inter-cloud intermediary pattern, multiple levels of connectivity
may be required.
In the simplest case, the CSP providing services to the CSC (the primary CSP) is hosting all of the services and
is providing the network connectivity to the CSC. In this case, the CSP can offer an SLA covering both the
cloud and network services.

In a more common case, the CSP providing services to the CSC (the primary CSP) will offer some of the hosted
services but will also be offering services from one or more secondary CSPs. The network connectivity
between the primary and the secondary CSPs may be offered as one of the primary CSP's services or it may
be provided by a distinct third party network provider.
As illustrated by Figure 8-9, the primary CSP is responsible for ensuring that the SLA between the primary
CSP and the CSC is met taking into account:
1) the network connectivity between the primary CSP and the CSC;
2) the services from the primary CSP;

3) the network connectivity between the primary CSP and the involved secondary CSPs;
4) the services from the secondary CSPs.

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