Babel

I recently had the opportunity to use Babel, a distance vector protocol designed to be versatile across both wired and wireless mesh networks. Upon initial usage, I found that Babel operates similarly to classic distance-vector routing protocols such as RIP and RIPng. However, it also incorporates ideas from other protocols such as DSDV, AODV, and EIGRP from Cisco. One notable difference is that Babel uses a variant of ETX link cost estimation as opposed to a simple hop-count metric.

Babel's performance on wireless mesh networks is particularly impressive given its robustness and efficiency in its default operation. Its link quality measurement is specifically designed for networks using the IEEE 802.11 MAC, though the paths chosen are reasonable for other types of networks as well. Additionally, Babel avoids route flapping, which is when routers frequently switch between two routes of similar quality, through the use of several techniques. This is in contrast to OLSR, which cannot rely on history-dependent route selection due to being a link-state protocol.

Notably, Babel is also efficient when operating on wired networks. In this setting, Babel uses a larger interval between hellos, performs split-horizon processing, and disables link quality estimation. Overall, I would highly recommend Babel as a versatile and efficient routing protocol option for both wired and wireless mesh networks.