A method, a router and a software are provided for routing communication traffic along a path in a communication network, being an IGP shortcut. The method comprises: providing an IGP shortcut prefix to a routing entity and storing the IGP shortcut prefix in a Routing Information Base (RIB); associating a new flag with an LSP associated with the IGP shortcut prefix, wherein the new flag indicates whether that LSP can serve for conveying traffic when implementing MPLS connectivity; storing information that relates to the new flag at the RIB; identifying LSPs associated with respective IGP shortcut prefixes which qualify to operate as next hop routing paths' candidates, wherein the qualified LSPs are each associated with a flag indicating that the respective qualified LSP is MPLS reachable; selecting an LSP to be a next hop routing path, wherein the selection is made from among the qualified LSPs; and forwarding traffic towards its destination via the next hop LSP.