Consensus nodes ranks & statuses

The KIRA network encourages consensus nodes uptime (i.e maintain an active status) by implementing a ranking system that fosters a dynamic and competitive environment to collectively promote network robustness and high participation levels. KIRA network utilizes the Tendermint consensus protocol, which ensures liveness by requiring a minimum of 2/3 + 1 of the consensus node set's total voting power to sign a block. While KIRA doesn't employ weighted voting and considers each node as having a single vote, the principle remains that it is not guaranteed for every node to sign every block as up to 1/3 of nodes can miss a block at any given time. This can be due to various factors, such as the random distribution of nodes around the world, limited networking connectivity between them, and the limited time that nodes have to wait for consensus votes. Accordingly, KIRA network's ranking system is designed to adapt to these variables. The system's parameters are fine-tuned by KIRA network governance to align individual node performance with the broader network health. This approach ensures high levels of participation while upholding the robustness of the network.

KIRA network's consensus nodes ranking system and the associated node statuses operates on block production and missed blocks counter and is measured through two performance indicators, streak and rank.

While a node's rank may decrease due to missed blocks, the ranking system accommodates for the unpredictability of block production chances and waits until a node misses a mischance_confidence number of blocks before considering the node offline. When a node’s status becomes offline, each subsequent missed block, or mischance counter, decreases the node's rank by a constant amount, mischance_rank_decrease_amount (set to 10 by default). However, if a node's status remains offline and their mischance score surpasses the max_mischance value, defined in the network properties, the system will categorize the node as inactive. An inactive status triggers a decrease in the node's rank by a percentage amount, defined by inactive_rank_decrease_percent (set to 50% by default).

Consequently, inactive consensus nodes get removed from the consensus node set and are barred from producing blocks. They can return to active status only when their operators signal readiness to produce blocks again, having resolved their internal issues, by using the activate CLI. The governance can adjust all these network properties to ensure a probabilistically fair decrease in a node's rank.

It may be useful for the governance to have the ability to reset all ranks simultaneously (e.g., incentivized games, etc.). For this purpose, the governance module has a dedicated proposal and corresponding voting permission.

Depending on it’s performance and activity, a consensus node can have one of the following statuses:

For planned maintenance where a consensus node must be offline, it can use the pause CLI to remove itself from the consensus node set. This will prevent the its rank from being impacted and the node will not be inactivated. When it is back online, the consensus node can use the unpause CLI to signal to the network that it is ready to rejoin the consensus node set.

Determining the optimal values for max_mischance and inactive_rank_decrease_percent depends on various factors, including the specific network conditions, the desired level of decentralization, average time for automatic recovery and the overall network performance. Based on the average block production rate, expected node uptime, and network latency of existing Cosmos ecosystem chains, the following initial values are proposed.

Nodes rank and statuses are stored in the x/staking module and can be queried using Consensus nodes & staking pools CLI.

Nodes rank and statuses can be queried using the Consensus node’s dedicated queries.