Hi Satya,
Transport of repository objects (that include roles) is a common subject here in SCN and is documented by SAP as well. Transport is usually done by the lifecycle management
Here's the official documentation regarding it:
Catalog Roles and Repository Roles Compared - SAP HANA Security Guide - SAP Library
Plus, I'd give special attention to the document Richard Bremer developed.
Here it is:
How to Define Standard Roles for SAP HANA Systems
I think these are great starters.
BRs,
Lucas de Oliveira