Forward and Reverse Bias regions for voltage versus current of diode

Below I have the graph of the voltage of a diode versus its current. As you can see, the forward bias region is when Vd>0 and reverse bias when Vd<0. My question is: In which region does Vd=0 fall in?

• Would deciding this question change anything at all about the actual behavior of the diode? – The Photon Oct 9 at 2:27
• I just need to know whether Vd=0 is forward or reverse bias. – Hector Oct 9 at 2:34
• Why? How will it change any circuit you design? – The Photon Oct 9 at 2:38
• I guess it does not. Another question for you, why is there a slight drop in Vd when Id increases? – Hector Oct 9 at 2:51
• who says it does? If you use the passive current convention, then $\frac{dV}{dI}$ is always positive for an ideal diode. – The Photon Oct 9 at 2:58