Responsiveness of future telecommunication networks under disaster situations

Disaster situations are a challenge for network operators because they result in an extraordinary large number of calls being opened simultaneously compared to normal operating conditions. The Quality of Service (QoS) and Quality of Experience (QoE) for the end user can be widely affected by peak loads and result in severe degradation, basically due to congestion on bottlenecks inside the network. In disaster situations, however, a high reliability of the connections is in particular required. In order to overcome the beforementioned issue, an extension for the well-known TCP named Multipath TCP (MPTCP) is investigated which delivers a TCP stream to different subflows sent over multiple interfaces and paths. Since MPTCP is an end-to-end transport-layer solution, it is independent of support by the network provider´s infrastructure and also works across multiple providers by delivering individual subflows over different networks. Simulation results show that MPTCP is suitable to reduce the load on individual access interfaces and helps to avoid congestion inside the network by shifting traffic to less loaded links so that a better QoS can be maintained. The performance of the network is enhanced by better utilization of the network capacity without increasing the link capacities.