Compatibility defines what environment and configurations Service Desk and CMDB run on.
This includes the official Certification Matrices and End of Life policies.
See End of Life for products that are no longer certified versions.
Certification Matrices are available for all CA products from support.ca.com, Support by Product or Solution, Service Desk (or appropriate product name), Recommended Reading and the Certification Matrix, Compatibility, End of Life or other documents located here.
Service Desk certification matrix link
And end of support link