A method of establishing traffic paths through a provider network, wherein a customer edge device is connected to a first provider edge node and to a second provider edge node via User-Network Interfaces; wherein said provider edge nodes (PE1, PE2) are interconnected directly or indirectly with provider core nodes (P1-P4) and further provider edge nodes (PE3, PE4) via Network-Network Interfaces to form said provider network; and wherein said provider edge nodes (PE1-PE4) and said provider core nodes (P1-P4) exchange routing information over said Network-Network Interfaces using a routing protocol; the method comprising: - requesting by said customer edge device a first traffic path through said provider network to be established from said first provider edge node; - within said provider network, calculating said first traffic path using said routing information and initiating setup of said first traffic path using a signaling protocol; - requesting by said customer edge device a second traffic path through said provider network to be established from said second provider edge node and to be disjoint from said first traffic path; and - within said provider network, calculating said second traffic path using said routing information and a constraint such that said second traffic path is disjoint from said first traffic path and initiating setup of said second traffic path using said signaling protocol; characterized by: - determining shared constraint information of said first traffic path and returning from said first provider edge node to said customer edge device via said User-Network Interface a data element indicative of said shared constraint information; and - forwarding said data element from said customer edge device to said second provider edge node to enable path calculation of said second traffic path such that said second traffic path is disjoint from said first traffic path using said shared constraint information as exclusion list; wherein said shared constraint information comprises Shared Risk Link Group identifiers of all provider network links used by said first traffic path; and wherein said data element comprises an unordered list of Shared Risk Link Group identifiers of said first traffic path. - requesting by said customer edge device a first traffic path through said provider network to be established from said first provider edge node; - within said provider network, calculating said first traffic path using said routing information and initiating setup of said first traffic path using a signaling protocol; - requesting by said customer edge device a second traffic path through said provider network to be established from said second provider edge node and to be disjoint from said first traffic path; and - within said provider network, calculating said second traffic path using said routing information and a constraint such that said second traffic path is disjoint from said first traffic path and initiating setup of said second traffic path using said signaling protocol; - determining shared constraint information of said first traffic path and returning from said first provider edge node to said customer edge device via said User-Network Interface a data element indicative of said shared constraint information; and - forwarding said data element from said customer edge device to said second provider edge node to enable path calculation of said second traffic path such that said second traffic path is disjoint from said first traffic path using said shared constraint information as exclusion list;