FabricPath is based on the TRILL standard with a few Cisco bonuses which builds on the concept of what if we could route a layer 2 packet instead of switching it.. Under the covers of FabricPath it uses the ISIS protocol, a MAC encapsulation, and routing tables to achieve all of the magic.owever, the concept of Trees in fabricpath also exists, tree's are used for the distribution of multidestination traffic, that is traffic that is not a single destination, so perfect examples of this would be multicast, unknown unicast and other flooding types.