A method is provided for selecting a telephony route for at least one digital stream serving a telephony destination. The method is performed within a first location server belonging to a first IP telephony domain deployed on at least one autonomous system. The autonomous system exchanges IP routing information with its neighbors designating at least one IP destination for updating an IP routing table. The method includes: the first location server searching for the IP routing information, the IP routing information including an identifier of a second IP telephony domain having associated therewith the at least one IP telephony destination, referred to as the destination identifier; and selecting the IP telephony route to reach the at least one telephony destination, applying a predetermined criterion for selecting the second telephony domain as a function of the destination identifier.