A Two-Phase Cloud Resource Provisioning Algorithm for Cost Optimization

Table 1

The key notations.

Notation	Description
	Set of VM types offered by cloud providers,
	Processing capacity of a VM instance of type
	Usage fee of an on-demand instance of type per hour
	Upfront payment of a reserved instance of type
	Usage fee of a reserved instance of type per hour
	Number of hours in a reservation period
	Hour index of the reservation period,
	Reservation decision,
	Number of reserved instances of type
	Number of on-demand instances of type at time
	Usage cost of on-demand instances at time
	Probability distribution of the workload