A method and arrangement in a communications network. The object is to provide a way of handing recourse management issues and admission control within an IP telephony system. The object is achieved by a topology aware resource manager collecting routing information concerning the IP network, obtaining resource information concerning resources within the IP network, creating a resource map by combing the routing information and resource information, and performing recourse management issues and admission control within the system by the resource map and by interacting with a gatekeeper.