webservices permissions error

Question

i created one webservice(insertstudent) in my local machine  using .net.
it is working fine.But i consume this webservice in my wpf application.
when i run this application my code  generate this error
Request for the permission of type 'System.Data.SqlClient.SqlClientPermission, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
plz tell me where i can set permissions....