Page 313 - Cloud computing: From paradigm to operation

Framework and requirements for cloud computing 1

I.6 Market transactions in inter-cloud intermediary pattern

Table I.6 shows inter-cloud use case for market transactions in inter-cloud intermediary pattern.

Table I.6 – Inter-cloud use case: Market transactions in inter-cloud intermediary pattern

Use case
Use case title Inter-cloud use case: Market transactions in inter-cloud intermediary pattern
Relevant roles CSP and CSC
Use case description – The primary CSP in an inter-cloud intermediary pattern (CSP-Intermediary)
mediates between CSPs meeting the CSC's quality requirements and provides
the list of selected CSPs to the CSC.
– The CSP-Intermediary coordinates multiple services offered by other CSPs.
Information flow – The SLAs of the CSPs are submitted to the CSP-Intermediary in advance.
– A CSC requests the CSP-Intermediary to select CSPs that provide a service
which satisfies the CSC's quality requirements.
– The CSP-Intermediary compares the CSC quality requirements with the SLAs
of other CSPs. Then the CSP-Intermediary discovers and reserves the CSP
resources that meet the CSC's quality requirements.
– The CSP-Intermediary returns the CSP candidate list to the CSC.
– The CSC selects a CSP or CSPs on the list.
– The CSP-Intermediary sends a cloud service adaptation request to the
selected CSP to invoke the service and adapt it to concrete cloud services and
resources.
– The CSP returns an adaptation response to the CSP-Intermediary.

High-level figure describing the 1. The CSC requests the service CSP
use case from CSP-Intermediary. The request
includes CSC's quality requirements.
CSP
CSC (Intermediary)
CSP
3. C-CSP intermediary
informs the CSC of
the candidate CSPs. 2. CSP-Intermediary compares the quality requirements
(including priorities) of CSC with the SLAs of
CSP multiple CSPs. The CSPs reserve the resources.
Y.3511(14)_FI.Tab6
4. The CSC chooses
some of the CSPs
and accesses them.

Derived requirements for The system is required to support:
cloud capability – Policy negotiation including SLA management among the multiple CSPs
including CSP-Intermediary in a pre-established group;
– Discovery, reservation, use and release of cloud resources in a dynamic
manner (i.e., not relying on the pre-configuration) on other CSPs within the
federation;
– Creation of the network connections in a dynamic manner (i.e., not relying on
the pre-configuration) from the CSC to the selected CSP that provides the
resources;
– Flexible reallocation of applications, to meet requirements at different stages
in its lifecycle, across multiple CSPs.

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