How can i provide role based security to notes in MS CRM 2011

See more:

ASP.NET

CRM

I am working on Notes in MS CRM 2011.

I have many roles over many entities. I want role based security to notes for any entity records.

let me explain what i want:

Suppose I have an entity namely E1. Role R1 and R2 has read and write access to E1.

But I want that user having role R2 can only upload and view notes for any record of entity E1.

Hope now my requirement is clear to all of you.

Please suggest me how can I achieve it using MS CRM 2011.