I'm thinking it's just different styles of the same ]They are different Link's, it would be absolutely impossible for them to be the same, and no Zelda fan in their right mind would believe that, The Zelda series spans over thousands of years, no one can live that long. (except for Ganondorf, but he's immortal)
As already confirmed by Miyamoto, there are many different incarnations of Link; however, they all share some distinct attributes, such as being left-handed and always wearing a green tunic.