how to redirect different user to different pages.

Question

In database i have username,password,department,..

while login time i have to check username and department(in department i have fields are IT, employee, HR )

if username and department(IT) it should b redirect to It Page only

if username and department(Hr) it should b redirect to HR Page only

if username and department(Employee) it should b redirect to Employee Page only

and login.aspx i have only two filed user name and password..

m not getting how i wl do this..

reply asap.. m waiting

thank You