A method of updating label-switched paths for forwarding data in a data communications network in response to a change in a network comprising the steps, performed at an updating node wherein the updating node is a node that has established that a change to its Forwarding Information Base, FIB, is required, the method comprising: receiving notification of a network change; in response to receiving notification of the network change, starting a first period timer at the updating node, the first period timer defining a first time period calculated to enable all nodes of the network which have to make a change to their FIB, based on the change in the network, to make the change; constructing a post-change label-switched path to a destination node in the changed network by adding any new forwarding information for the post-change label-switched path to the FIB of the updating node, but not yet switching to the post-change label-switched path; and characterized by: determining whether a next hop node toward the destination node in the post-change network is a downstream node in the pre-change topology, a downstream node comprising a node from which the path to the destination is less than or equal to the path to the destination from the updating node and, if so, forwarding data to the next hop node using the post-change label-switched path using the new forwarding information FIB as though the first period has terminated, otherwise, waiting until termination of the first period, and then forwarding data using the post-change label-switched path using the new forwarding information in the FIB. receiving notification of a network change; in response to receiving notification of the network change, starting a first period timer at the updating node, the first period timer defining a first time period calculated to enable all nodes of the network which have to make a change to their FIB, based on the change in the network, to make the change; constructing a post-change label-switched path to a destination node in the changed network by adding any new forwarding information for the post-change label-switched path to the FIB of the updating node, but not yet switching to the post-change label-switched path; and characterized by: determining whether a next hop node toward the destination node in the post-change network is a downstream node in the pre-change topology, a downstream node comprising a node from which the path to the destination is less than or equal to the path to the destination from the updating node and, if so, forwarding data to the next hop node using the post-change label-switched path using the new forwarding information FIB as though the first period has terminated, otherwise, waiting until termination of the first period, and then forwarding data using the post-change label-switched path using the new forwarding information in the FIB. determining whether a next hop node toward the destination node in the post-change network is a downstream node in the pre-change topology, a downstream node comprising a node from which the path to the destination is less than or equal to the path to the destination from the updating node and, if so, forwarding data to the next hop node using the post-change label-switched path using the new forwarding information FIB as though the first period has terminated, otherwise, waiting until termination of the first period, and then forwarding data using the post-change label-switched path using the new forwarding information in the FIB.