Microsoft release more details about how Azure Stack will be licensed when it’s available in mid 2017. And what is Azure Stack? Think Azure Services running on on-premises hardware. This useful Microsoft blog post (http://bit.ly/2nmBL2q) explains that Azure Stack will be charged on a consumption basis (like Azure Services normally are) but prices will be lower since customers are providing their own hardware and facilities.
Azure Stack hardware will be available from Dell, EMC, HPE and Lenovo and this too will be available on a pay-as-you-go basis if required.