What do you mean by collective immutability? can you explain more please?

+1 vote

1 Answer

+2 votes
Any notion of "immutability" is not absolute. It refers to a restriction on the conditions under which the supposedly immutable thing could change.

For example in public blockchains like bitcoin, immutability can be undermined by a 51% attack, where the holders of a majority of the mining power can rewrite the chain's history.

In MultiChain, immutability is provided by the round-robin method, where permissioned "miners" sign blocks in rotation with each other. So immutability can be undermined if a majority of these entities collectively decide to rewrite the chain's history.

There is no such thing as absolute immutability in computer systems, until data is moved to a non-rewritable storage device.
answered Nov 10, 2016 by MultiChain
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