Route Stabilization in Infrastructured Wireless Mesh Networks: an OLSRD Based Solution

This paper presents a route management protocol for multi-homed infrastructured WMNs aiming to preserve active sessions of mobile nodes. Every mesh access point (MAP) has at least one MAP interface configured as a traditional AP and another one dedicated to the WMN backhaul. The clients are mesh-unaware to avoid installing special software on them. We propose a mechanism based on dynamic IP-within-IP tunnels to pin routes and guarantee (in time) the communication between clients and Internet gateways. MAPs select the best gateway for each new connection and maintain tunnels for the connection duration to allow the seamless communication during the whole flow life. When a client changes MAP, the old and the new one exchange tunnel information so that the new MAP reestablishes tunnels with the correct gateway ensuring smooth packet delivery. The protocol is an extension to OLSRD, and has been implemented in Linux-based MAPs. Evaluation is carried out both emulating complex scenarios with user mode Linux (UML) and in a real WMN testbed.