How to use transctions or transaction Scope in ADO.NET

Question

Hi...

In my scenerio , i have to insert data to master table and details table . For example consider the details given below.

Function 1 : Insert data to employee master table.
Function 2 : Insert gridview data to employee details table, here employee id from employee master table is needed to pass.

I want to this using 3 tier architetcure . I can call this only in Data access layer , and if any of the functions failed both tables must not be saved , 
can any one help me on this scenerio..
Thanks and Regards 

Sankar