Question for someone who has the knowledge on POS / POW.
What happens when the hashing becomes so low on POW that POS is the only thing securing the coins? Is this a likely event? How secure would the system be then? Can the coin survive solely on POS in a secure manner?
IMO, PoS alone will secure a coin as long as enough coins are being staked.
Rat4 of blackcoin had a discussion about it and even showed a successful attack against Mint , (when their PoW was low.)
https://bitcointalksearch.org/topic/security-analysis-of-powpos-hybrids-with-low-pow-reward-551861His recommendation was going PoS only and dropping the PoW when the PoW gets too low.
Basically the reason
ZEIT & MINT dropped PoW and went PoS only was his findings, as in the beginning they were both hybrid like HBN.
However neither
ZEIT or MINT use a Checkpoint Server.
HBN does use a checkpoint server, so it may block some or all of those potential problems from a low PoW hash rate, Tranz would have the most knowledge on that.
FYI:
Here is some additional info for you from
https://cryptocointalk.com/topic/9592-hbn-trouble-shooting-guide-syncing-and-checkpoints/ _____________________________________________________________________________
What are checkpoints?
Checkpoints are blocks in the chain where all clients agree are correct. These points allow for additional security in the event of some type of attack, or coding malfunction. Where clients are in disagreement about the correct height of the chain.
There are two types of checkpoints. Hard coded and sync checkpoints. Hard coded checkpoints are put in the source code manually, generally done with major revisions. Sync Checkpoints are issued from a dedicated server at fixed or manual intervals.
Will HBN always use sync checkpoints?
For the foreseeable future HBN will use checkpoints. This is very helpful while the network is still young. As the hash rates increases and more nodes are connected and staking, checkpoints can be lowered or eventually removed.
This does add some centralization to the network, but the trade off for security is worth it._______________________________________________________________________________
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about two days into a bootstrap and this is the point I am at.
