A method for propagating at least one route for at least one digital stream between a first location server of a first IP telephony domain and a second location server of a second IP telephony domain. The first location server belongs to a first autonomous system and the second location server belongs to a second autonomous system. The method includes sending digital stream routing update messages to the second location server. The update messages contain information for managing quality of service, and, prior to being propagated towards the second server, the information is updated by the first server. The information includes at least one of the following: information about a quality of service component associated with at least one autonomous system, referred to as a system component; and information about a quality of service component associated with at least one IP telephony domain, referred to as a domain component.