Temporally ordered routing algorithm
The Temporally-Ordered Routing Algorithm (TORA) is an algorithm for routing data across Wireless Mesh Networks or Mobile ad-hoc networks.
It was developed by Vincent Park at the University of Maryland and the Naval Research Laboratory. Park has patented his work, and owns Nova Engineering, who are marketing a wireless router product based on Parks algorithm.
Operation
The TORA attempts to achieve a high degree of scalability using a "flat", non-hierarchical routing algorithm. In its operation the algorithm attempts to suppress, to the greatest extent possible, the generation of far-reaching control message propagation. In order to achieve this, the TORA does not use a shortest path solution, an approach which is unusual for routing algorithms of this type.
TORA builds and maintains a Directed Acyclic Graph rooted at a destination. No two nodes may have the same height.
Information may flow from nodes with higher heights to nodes with lower heights. Information can therefore be thought of as a fluid that may only flow downhill. By maintaining a set of totally-ordered heights at all times, TORA achieves loop-free multipath routing, as information cannot 'flow uphill' and so cross back on itself.