I have been using Cisco Data Center Network Manager for more than a year.

I have been using Cisco Data Center Network Manager for about two years.

I have been using Cisco Data Center Network Manager for approximately five years.

I have been using the product for eight to ten years. 

I have been using the solution for a couple of years.

I have been using the solution for more than ten years. 

I have been using the solution for almost five years.

I've been using this solution for five years.

We have been using this solution for 14 years, and it is implemented on-premises, Google Cloud, Amazon, or Azure.

I've been providing service on this solution and using it for over 10 years. 

I've been using this solution for one and a half years. 

I've been using this solution since it's been on the market. 

We have not been using this solution for a very long time but it has been about two years.  

I have been working with the Cisco Data Center Network Manager for four years.