Fromnode
It's the starting point of a street.
Street
A street is a segment of a road, or of an avenue, or of an highway, etc.
It is uniquely identified by the starting node (fromnode) and the street identifier (streetIdno).
A generic set of streets can be indicated as a corridor.
The concept of corridor maps any type of road sequence related to the common user's experience (a road, an avenue, an highway, etc.).
In the figure you can see two corridors: the Red Avenue and the Blue Road.
Speed
The average speed measured on a specific street, expressed in meters per second (m/s).