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Subject: Re: [Bitcoin-development] "network disruption as a service" and
proof of local storage
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> On Mar 27, 2015, at 8:16 AM, Matt Whitlock <bip@mattwhitlock.name> wrote:
>=20
> Isn't the goal of this exercise to ensure more full nodes on the network?
Basically we're talking about a form of Sybil defense and better quantifying=
true blockchain resiliency by proof of storage.
In this case the goal is to see if we can prove the number of distinct digit=
al copies of the blockchain. This is actually a tricky problem because it wi=
ll (always?) devolve to inferences from response timing, and we are running o=
ver a heterogenous network with heterogeneous machines.
It would be extremely impressive to achieve a reliable mechanism for discern=
ing a local copy exists under these constraints, particularly without false p=
ositives and false negatives, and without imposing very substantial one-time=
encoding costs, e.g. on par with doubling the verification cost.=20
I think while its a difficult cost-benefit analysis, even code complexity as=
ide, it's interesting to discuss all the same!
Simply having many unique IP addresses possibly accessing the same unique co=
py provides a different (if any) benefit. E.g. Tor uses IPs as a cost factor=
, but (until recently?) didn't even factor in things like them all being the=
same Class C.=20=
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