There are a number of considerations to make when selecting validators. Prior to Xi’an release in 2023 when Radix will be fully sharded, there are 100 validators who take part in consensus and earn emissions, so we must choose carefully between these validators to delegate our stake. Here’s a guide for some of the considerations to make when selecting validators:
How many?
It is advisable to delegate your stake to a number of different validators. This reduces your risk of missed rewards in the event of a validator going offline or suffering some downtime. A general rule of thumb is to select 5 validators. There are however no limits, so you may choose to stake with more or less.
Decentralisation
In the interest of ensuring that the network is truly decentralised, it is preferable for no single validator to have too much of the total stake. In an ideal world, the top 100 validators would each have 1% of the total stake, so validators who are already above 2% total stake should be avoided.
Security
Similarly to the decentralisation argument above, if one or only a small number of nodes have a considerable amount of stake, this can put the security of the network at risk - for example a malicious actor only would only have to attack a smaller subset of nodes to cause disruption. As above, it is advisable to stake on nodes with less than 2% stake.
Fees
Validator fees are automatically deducted by the protocol and range from 0% - 3% typically. Many validators operate nodes with 0% fees, however it should be considered that in order to operate robust infrastructure with backup nodes, monitoring systems and DDoS protection requires a significant financial outlay and it therefore may be a false economy to stake only to 0% fee validators. Many validators will also not be able to sustain 0% fees indefinitely so the best advice is to contact them to understand what their longer term fee strategy is. (remember it takes ~2 weeks to unstake, so any benefit of 0% fees now could soon be lost if a validator then increases fees to 5% and you need to unstake). Fees also have much less impact on your staking rewards than uptime (see thread here).
Uptime
Each validator is required to take part in consensus rounds in order to earn emissions. The number of consensus proposals made are counted along with any proposals that are missed to determine the validator’s uptime. If a validator’s uptime drops to less than 98% in any single epoch, no emissions are earned for that epoch. It is therefore recommended to keep an eye on the uptime metric which is recorded on the official Radix Explorer, or on community tools such as Radixscan and Radix Dashboard. This uptime metric is measured over the last 500 epochs (~12 days) and should be 99.9%+ to ensure consistent high performance.
Geography/Server Provider
Validators are spread throughout the world, the locations and server providers of each can be found using the StakeSafe Validator Dashboard. In the interests of decentralisation, it is advisable to choose validators from under-represented geographies. Furthermore, many validators use cloud providers to host their servers. It is therefore advisable to consider providers who already host a large percentage of Radix validators such as Hetzner and Amazon, in favour of smaller data centres. Otherwise an outage at any one data centre could be very detrimental to the performance and security of the network.
Change Log:
12/09/2022 - removed Radix.earth and added Stakesafe Validator Dashboard
16/11/2022 - removed recommended fee level and updated uptime length from 150 to 500 epochs