There is provided a method of forwarding a traffic flow in a communications network having at least one network node for which network traffic is selectively prevented from transiting the network node. The method includes the step of selecting a specified category of network traffic that is to be prevented from transiting the network node. The method also includes the step of determining a path within the network for forwarding the traffic flow, whereby the network node is excluded for transit in establishing the path where the traffic flow is identified with the specified category of network traffic.