Ask HN: Which license management solution do you use?

Which is the license management solution that you would recommend. Given the following feature requirements,

1.Metered Licensing (hard+soft limits)

2.Single User Fixed Duration License (FDL)

3.Perpetual Single User License

4. Aggregate Use time license (Time trial)

5. API for mobile, web and legacy integration

6.API for integrating to reporting solutions

7.Self service portal for customer's customer

8.Multi-tenant configuration support