Traffic flow confidentiality in federated networks - Multi-topology routing and security options

Traffic Flow Confidentiality (TFC) aims to prevent analysis of traffic flows. According to the principles of Protected Core Networking (PCN), TFC should be provided as a service in the network and not implemented by the users. Since provisioning of TFC in the entire network might not be practical or economical feasible, solutions are required for forwarding traffic on paths where sufficient TFC is employed. There are mainly two challenges related to this, the first one is to establish different routing-topologies for TFC and non-TFC paths, and the second is how users should signal their requirements for TFC to the network. This paper discusses using multi-topology routing for path selection and then proposes a signalling scheme that is based on option-headers.