sunnya97

The Cooper Union in NYC used to do something similar for over a century until they were forced to stop in 2014 due to a combination of many financial factors, including the financial crisis of 2008.

You can read the entire story of it here: https://en.wikipedia.org//wiki/Cooper_Union_financial_crisis...

Check out this interview I did for the Epicenter Podcast with Enigma, a company building an MPC implementation, for a decent intro to what MPC is.

https://www.youtube.com/watch?v=ajAUByRZGWM

I spend a lot of time on YouTube watching what I call “educational channels” on topics ranging from science to geopolitics to philosophy. Here's a list of a bunch of them.

https://medium.com/sunnya97/educational-youtube-channels-52d...

In PoW, you are trusting the miners.

Some other random generation techniques include commit-reveal schemes, BLS Threshhold Relays, VRFs, Private Hashchains, etc.

Also, two other comments regarding weak subjectivity:

When you join the bitcoin blockchain, you need some trusted source to tell you the hash of the correct genesis block.

Also, if you want to follow a shorter fork chain like Ethereum Classic, you also need weak subjectivity to tell you the first block immediately after the fork, otherwise you might be tricked onto the longer malicious fork, Ethereum :P

You would have to compromise the devices of validators who have atleast 2/3 of the voting power.

In Bitcoin, just compromise the devices of mining pools that have atleast 50% of the hashing power, and reconstruct a chain that is longer than the current canonical chain, thus rewriting the chain history.

What centralized authority? The keys in the genesis block aren't owned by a single actor, but by multiple.

You can keep the validator set static all the time (use the ones from the genesis block), this might be useful for private chains. But Tendermint also allows for dynamic validator sets. This is useful for Proof of Stake, where validators can come and go, and their voting power can change in accordance with changes in their stake deposits.

It's not a single private key. There are a lot of validators, even in the genesis block, and we assume that at least 2/3 of these validators are honest.

Unlike traditional BFT algorithms that have multiple validators with equal and static voting power, what Tendermint does is each validator has coins staked to them. These coins can be either the validator operator's own coins or coins that are "delegated" to them by other users (think of these as Proof of Stake "mining pools"). Their "voting power" in the BFT consensus is weighted by their coin stake.

Validators can come and go as part of the protocol, so essentially the previous validator set signs on the next validator set. Also, more people can delegate stake to existing validators.

When a validator leaves, there is an unbonding period before they are allowed to withdraw their coins (this is the to put a minimum time length on a long-range attack). Tendermint also solves the nothing-at-stake problem because if a validator doubles signs on two competing blocks, this is byzantine behavior that is recognized and punished by slashing their staked coins on both forks (staked coins act as both weight for BFT voting power and as security deposits).

One assumption that Tendermint makes as opposed to Nakamoto Consensus systems is that at least 66% of validators have to be running in order for the system to make progress. In Nakamoto consensus, even if a lot of miners are down, the existing miners can still propose blocks. This is, however, a double edged sword, as what seems top be "down validators" might actually be a network partition. In Nakamoto consensus, even a temporary partition would lead to parallel forks, while in Tendermint, this would not happen, as the system will stall instead of forking. Nakamoto Consensus is availability favoring, while Tendermint is consistency favoring.

Tendermint works very well for both Proof of Stake and Proof of Authority systems, which is makes it particularly useful for both public and private settings, and deals with byzantine faults in both, as opposed to just crash faults as in protocols like Paxos and RAFT.

Adding on to what coinculture said, the traditional BFT nature of Tendermint consensus gives it a lot of benefits over Nakamoto consensus such as 1-block finality and safety guarantees in asynchronous environments.

Traditionally, these BFT algorithms did not work in public settings, and only worked with fixed validator sets. However, with the conceptual invention of Proof of Stake, we realized we can use cryptoeconomics to facilitate validator set changes in a public network.

And yes, 2/3 of nodes are set to be honest. However, just in case you weren't aware, it's pretty not well known, but Nakamoto consensus also has a 2/3 threshhold due to the game theoretical vulnerabilities caused by a process known as selfish mining.