How Connect Oracle DB to Visual Studion

Hello Friends Now  a days i doing my summer training From CDAC Jaipur.  My field of training is ORCALE .  I create a database in Orcale and now iwant to connect with Visual Studio for Font end of My Project.

But when i am trying to make a connection in  " SERVER Explorer" it showing an error that is:

 

 

 

 

I don't know how to resolve this error please help me it is very urgent.

Thanks in Advance........