Rerouting for Handover in Mobile Networks with Connection-Oriented Backbones: An Experimental Testbed

The rerouting of connections for handover in a broadband mobile cellular network is investigated. We address networks with a connection-oriented backbone, which supports quality-of-service (QoS). Moreover it is assumed an IP-style multicast on top of the connection-oriented network. We advocate to utilize the IP-style multicast in order to reroute connections for handover. Three rerouting schemes are proposed, which are based on the IP-style multicast. One of the schemes realizes a predictive approach, where a call is pre-established to potential new base stations by setting up a multicast tree with neighboring base stations as leaf nodes. This approach reduces the handover latency caused by rerouting to an absolute minimum and improves communication with strict time constraints and frequent handover. For experimental investigations of the rerouting schemes a testbed is set up, which is based on an open, nonproprietary, experimental networking environment. Its signaling software offers a direct many-to-many communication, rather than requiring one-to-many overlays and the switching hardware supports scalable and efficient multicast by cell-recycling. The testbed is used to proof the feasibility of the approach and for performance evaluation of the rerouting scheme.