The present invention relates to methods and arrangements for arranging a distribution tree in a Peer To Peer P2P streaming system. The system comprises a bootstrapping server (10) that creates an external distribution tree based on received register messages from participating operator external clients (2, 3, 4). The method comprises the following steps: —Configuring an operator controlled node (7) to be a regular node in the created external distribution tree. Configuring the operator controlled node (7) to be a parent node for participating operator internal clients (1, 5, 6).