I am creating a network dataset using the roads polylines contained in the OS Meridian 2 data set, in order to eventually calculate road journey distances. I have been considering connectivity and elevations, and have been using the sDNA manual - network preparation module as guidance. This suggests that the 'link-node rule' applies to the Meridian 2 data set whereby "Intersections are not allowed in the data at all; ALL lines where they touch MUST have coincident endpoints. Where links don’t join at their endpoints this is shown by providing elevation or grade separation data – endpoints are assumed not to join unless their elevation and grade separation match. This data is provided in a separate layer of points, cross-referenced to the lines whose elevations they represent (OS Meridian does this)." - I have the separate layer of points (link nodes) which contains a 'levels' field. For example, if a road over a bridge can be accessed then a level value of 0 is used; a value of 1 is used when there is no access from one road to the other at an intersection.
It is then recommended to convert from this format to a network with a 'coincident endpoint connectivity rule'. However, the guidance seems to stop there. In order to do this for 'link-node rule' data, the manual simply suggests that I get in touch with the sDNA via this website, as there are tools available for doing this conversion.
Can anyone offer advice on this issue? I'm not sure what I can do next.
For reference, here is the full article provided by sDNA: http://www.cardiff.ac.uk/sdna/wp-content/downloads/documentation/manual/sDNA_manual_v3_3_alpha0/network_preparation.html