[DSTAR_DIGITAL] Linking vs. Source Routing

[Nicholas]

I may be asking a question that has already been answered. What is the 
difference between Linking (UR: KJ4MMCCL) and Source Routing (UR: /KJ4OXTC)? 
This is something I have yet to figure out.

Thank you and 73s,
Nick KF4SEK
Cocoa, FL