1. A method for determining a path calculation from a source node to a destination node over a multi-domain network, the method comprising: receiving a predetermined sequence of domains for communicating information from the source node to the destination node; determining a link type for each of a plurality of links in the predetermined sequence of domains; modifying the link type of one or more of the plurality of links such that the plurality of links are unidirectional links towards a destination node; and determining a path along the predetermined sequence based on the modified plurality of links.