role level security and row level security usage?

Hey,

I have to admit that I have difficulties in understanding your question, are you asking for the differences between

Row Level Security (RLS) in the relational engine of SQL Server and RLS in Power BI or are you asking for differences in 

RLS in SQL Server Analysis Services Tabular and RLS in Power BI

Basically, from a conceptual point of view, it's all the same. The number of rows is filtered by a permission that just allows to see a certain set of rows.

RLS in SSAS Tabular and Power BI is also technical the same, because the Data Model of Power BI is the "same" as the Data Model of SSAS Tabular.

But you have to be aware, that you have to define RLS in SSAS Tabular if you are accessing the Data Model using a Live Connection.

Hm, wondering if this of any help

Regards

Tom