Ethereum 2.0 is now closer to release than ever. The team is currently targeting the v0.4 release with a single client testnet and a highly available network that is resilient to forks and validator inactivity while allowing new validators to join the network.
The team, according to the official announcement, will be hosting a “medium-sized deployment” of validators and beacon chain nodes. They are also confident that the infrastructure will be able to scale out to hundreds and thousands of validators.
“We’ve tested multiple small configurations with deployments of 32 validators and we’re confident in the infrastructure to scale out to larger deployments of hundreds or thousands of validators.”
It further states that one of the major goals of the test network is to observe the clients’ behavior as the scale increases. Moreover, after releasing the updates to the cluster, new features will be gradually released and in case an update is causing a regression, they will simply roll back the update and resolve the issue.
“Our first release is NOT a simulation, but a real system that will give users a good idea of what to expect at mainnet.”
“Casper proof of stake consensus is applied in order to finalize block checkpoints which have received a consistent amount of votes over time.”
Information like beacon nodes synch blocks will be provided in real time and nodes can also peer with others while the new nodes will fully sync within seconds.
Beacon nodes will be running the Casper Proof of Stake fork-choice rule to decide the head and resolve network forks.
Moreover, the network can handle skip slots where validators are inactive and chain will still proceed as normal. In case there are more than 4 epochs since the last finalized block, the protocol will penalize validators.
Other features include validators using RANDO, users able to run validators clients, and data storage through persistent disk storage by beacon node among others.
As for what is not included, signature verification, use of Simple Serialize, beacon chain transfers, shard crosslink processing, and voluntary validator exits are being disabled. Also, as of now, they don't have a mechanism for validators to slash other validators.
Before the testnet version could be released, the team has bugs to fix and address issues as for the next few weeks and months, the priority is to ensure client integrity and long-running chain.