In Act 1, Scene 2, lines 189-260 of The Tempest, what is the relationship between Prospero and Ariel?

Ariel has great admiration and respect for his master, Prospero.  He addresses Prospero with the words, "All hail, great master, grave sir, hail!"  He also obeys to the letter all the commands of Prospero and enjoys telling him in detail how he carried out his plan. He delights in serving and pleasing Prospero.  In turn, Prospero is greatly pleased with Ariel. When Prospero tells Ariel there is more to do, Ariel is disappointed because he believes he has earned his liberty, which Prospero had promised him.  Prospero rebukes Ariel sternly, almost as a parent would a child.  However, it is obvious that Ariel feels shame for demanding freedom when Prospero still needs him.  He answers Prospero's questions with very short answers which suggest shame and remorse. He is reminded by Prospero how the witch, Sycorax, had imprisoned him (Ariel) in a "cloven pine," and how Prospero had freed him from this torment; thus Ariel is bound to Prospero by ties of gratitude.