Revision with unchanged content. Today's network providers face a lot of issues by designing their networks. They have to provide a certain Quality of Service and must furthermore agree on Service Level Agreements. Thus the availability of the network and its potential to transport all traffic is a main goal for each network provider. If there is no network failure a provider can monitor the network load and increase the capacity where needed. Designing a network in case of network failures is much more complicated. The method presented in this book targets this topic by optimizing a backup path layout using explicit routing. Therefore the relevant failure scenarios and their occurrence probability are determined. The presented algorithm can for example be implemented by using Multiprotocol Label Switching (MPLS). Target audiences are network service providers or other persons managing a network with high availability requirements.