Is the Shapiro Delay a Result of Space Curvature or Time Dilation?

[Zman]

How is the Shapiro Delay interpreted in GR?
Is it that the curvature of space is increased around a massive body causing the path length to increase?
Or is it because time dilates making the speed of light appear to slow?
Or something else?

 

[MeJennifer]

The term delay in "Shapiro delay" is of questionable use. The light travel time simply increases when a massive or energetic source is near the travel path. If you use light travel time as a measure of distance (which I think is a very practical thing to do) you could say that distances increase between two points if a massive or energetic source is in the vicinity of the path between them.