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6a) OOF Processing - cloud_net_value input in Multi-objective Optimization (need OOF code changes)
Casablanca Goal for implementation simplification
Select one of the clouds which meets the cost hard constraint, e.g. cost <= x. This is similar to current capacity check implementation, where one of the cloud which passes the capacity check is selected.
Stretch Goal for Casablanca
Each service specifies an service-specific objective function that is stored as part of the service-specific policy and is used by OOF to evaluate the candidate <cloud owner, cloud region>. For simplicity of the example, let’s consider service that consists only of one VNF instance. The objective function has two components:
- distance from customer location to the VNF - the service designed assigns a weight for the distance: wd
- the cost of deploying the VNF in a location - the service designer assigns a weight for the cost: wc
OOF optimization function: min (wd*distance + wc*cloud_net_value)
If the service does not care about the cost at all, it would set wc = 0. If the service designer wants to minimize cost, he could set wd=0. Note that candidates that are too far can be eliminated by a distance constraint even before the optimization. For example, if the service has a distance constraint of at most 100 kilometers, then only those <cloud owner, cloud region> within 100 kilometers to the customer location would be considered in the objective function evaluation.
If the service designer wants to trade off between distance and cost, for example, they might set wd = 1, wc = 2. This would mean that one $1 increase in price is as valuable as 2 kilometers in distance.
<cloud owner, cloud region> Candidate 1: $100, 100 kilometers => value: 300
<cloud owner, cloud region> Candidate 2: $150, 80 kilometers => value: 380
<cloud owner, cloud region> Candidate 3: $50, 190 kilometers => value: 290 <- pick this one
Step 6. OOF → SO - Return the target <cloud owner, cloud region> for the Service Instance + deployment-intent per vnfc
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