AODV–based routing for payment channel networks

Payment Channel Networks such as the Lightning Network (LN), Raiden or COMIT were created to tackle the scalability problems of their underlying blockchains, by moving from expensive and slow on-chain transactions to inexpensive and fast off-chain ones. However, those networks are unregulated and decentralised, comprise point-to-point channels that may be opened or closed without coordination or warning, and fees may change at any time – making routing over these networks a hard problem. In addition, by connecting different blockchains using such off-chain networks, an immense network of channels will evolve which is under continues change. Routing needs to take into account the current network status, availability and distributions of channels’ funding, fees for each node, and exchange rates between different currencies. In this work, we identify requirements for such a routing protocol and adapt the Ad-hoc On-Demand Distance Vector Routing (AODV) protocol to this end by enhancing the messages with information on fees and exchanges rates. This approach allows finding suitable routes through the network, while intermediate nodes can maintain their economic incentives. We simulate different network topologies and evaluate the adapted AODV protocol on 3 different networks of 500, 1,000 and 5,000 nodes.