I get stuck with the following two criteria both about the uniqueness of plane embeddings of a given planar graph. The first one says that a planar graph admits unique plane embedding iff it is a subdivision of 3-connected planar graph (e.g. from the book "Planar Graphs: Theory and Algorithms"). The second one (is from paper "The uniquely embeddable planar graphs") tells that uniqueness holds iff it is 3-connected planar plus some exclusions. I suppose they are based on two different definitions of equivalence. As for me I consider plane embeddings equivalence as an equivalence of the respective complexes. Indeed, each plane graph is in fact a triple $(V,E,F)$ where $F$ denotes set of faces. So the equivalence means that there is a map that translates the first complex to another one that keeps incidence between vetices and edges, edges and faces, vertices and faces.
My question is particularly under what definition the first criterion holds ? The proof that the book gives is a bit untransparent for me in that matter because the definition of uniqueness that it gives is not that strict.