Routers in IP networks, which were initially designed to carry data services only, need special protocols to seamlessly carry real-time services such as voice and video. As one of the leading activities in this context, IETF RTGWG working group has been working on standardizing IP Fast Re-Route (IPFRR) protocols which provide a complete alternate path coverage against network component failures. Multiple Routing Configurations (MRC) is a Multi Topology Routing (MTR) based IPFRR technology targeting a complete coverage. In this paper, we evaluated the performance of virtual topology construction mechanism of MRC on various realistic network topologies. The performance results show that the minimum number of virtual topologies required by MRC to provide full alternate path coverage and the alternate path lengths depend on the link density and other structural properties of network topologies.