Real-time and multimedia applications have grown enormously during the last few years. Such applications require guaranteed bandwidth in a packet switched networks.
Moreover, these applications require that the guaranteed bandwidth remains available
when a node or a link in the network fails. Multiprotocol Label Switching (MPLS)
networks cater to these requirements without compromising scalability. Guaranteed
service and protection against failures in an MPLS network requires backup paths to be
present in the network. Such backup paths are computed and installed at the same time a
primary is provisioned. This thesis explains the single-layer restoration routing by placing primary as well as backup paths in MPLS networks. Our focus will be on computing and establishing backup paths, and bandwidth sharing along such backup paths. We will start by providing a quick overview of MPLS routing. We will identify the elements and quantities that are significant to the understanding of MPLS restoration routing. To this end, we will introduce the information locally stored at MPLS nodes and information propagated through routing protocols, in order to assist in efficient restoration routing. L2VPNs and VPLS will also be covered in the end of this thesis. In the end SDN (software defined networks) will be introduced
