A ROOT BRIDGE NODE AND A METHOD IN A ROOT BRIDGE NODE FOR HANDLING TOPOLOGY CHANGES IN AN ETHERNET NETWORK

A method in a root bridge node for handling topology changes in an Ethernet network is provided. The Ethernet network comprises groups of bridge nodes that are only connected to each other via the root bridge node. The root bridge node and the bridge nodes may be configured to run a Spanning Tree Protocol, xSTP, to prevent ring loops among the bridge nodes in the groups of bridge nodes. The root bridge node comprises a number of ports, which number of ports is associated in the root bridge node with physical addresses of user equipments connected to the bridge nodes in the groups of bridge nodes. The number of ports is configured by the xSTP to have the role of designated ports. The method comprise: associating each port of the number of ports with one of the groups of bridge nodes; receiving a Topology Change Notification, TCN, on at least one port of the number of ports from a bridge node in one of the group of bridge nodes; identifying which group of bridge nodes that the at least one port which received the TCN is associated with; removing in the root bridge node, at least partly the associations between port or ports which are associated with the identified group of bridge nodes, and the physical addresses of the user equipments connected to the bridge nodes; and sending the TCN out on the port or ports of the number of ports which are associated with the identified group of bridge nodes. A root bridge node is also provided. La présente invention concerne un procédé dans un noeud de pont racine destiné à gérer des changements de topologie dans un réseau Ethernet. Le réseau Ethernet comprend des groupes de noeuds de pont, uniquement connectés ensemble par le biais du noeud de pont racine. Le noeud de pont racine et les noeuds de pont peuvent être configurés pour exécuter un protocole Spanning Tree (xSTP), afin d'empêcher que l'anneau ne boucle parmi les noeuds de pont dans les groupes de noeuds de pont. Le noeud de pont racine comprend plusieurs ports, lesquels sont associés, dans le noeud de pont racine, à des adresses physiques d'équipements utilisateur connectés aux noeuds de pont dans les groupes de noeuds de pont. Les différents ports sont configurés par le xSTP pour avoir le rôle de ports désignés. Le procédé comprend : l'association de chaque port, parmi les différents ports, à l'un des groupes de noeuds de pont ; la réception d'une notification de changement de topologie (TCN) sur au moins un port parmi les différents ports d'un noeud de pont d