Subject: Re: [Bitcoin-development] Protocol extensions

From: Michael Grønager <[email-masked]>
Date: Thu, 22 Dec 2011 13:42:08 +0100

Just adding to Joels comment:

The only one with an incentive to do validations are miners (otherwise they could risk having their mined blocks invalidated later by less lazy miners) and the ones who are to send and accept a transaction. In a distributed stored and validated block chain setup, you would hence need to ask some miners if the inputs to a transaction is valid or download all the chain yourselves.

The latter is what we do today and will not scale, the former is the logical consequence of a non-enforced random validation approach - so this will give us super nodes, namely miners, and at some point they could choose to also charge for the validations. It might be the direction we are moving towards, but then the p2p network is only for the miners and the rest of us can connect through https and use json-rpc to post transactions etc to them. I do, however, prefer a setup where we keep everything really distributed...

/M

On 22/12/2011, at 13:14, Joel Joonatan Kaartinen wrote:

> On Thu, 2011-12-22 at 11:52 +0000, Andy Parkins wrote:
>> Why should they have to?  Joining the network as a node is very low cost to 
>> the other nodes.  You can't force any node not to be lazy, since their option 
>> is to disconnect themselves.  As to maliciousness, that is defended against 
>> because when a node negative announces a transaction, that transaction is 
>> going to be checked (note that there is still no implicit trust) -- if a node 
>> is incorrectly negative-announcing then it can justifiably be kicked.
> 
> a node that is not doing any checking themselves can not reliably
> forward failed verifications without getting the blame for doing faulty
> work. Those nodes would then have the incentive not to relay the failed
> verifications. This ends up making it important to know which nodes will
> be checking transactions or not so you don't isolate yourself from other
> nodes that are also checking transactions.
> 
> - Joel
> 

Michael Gronager, PhD
Owner Ceptacle / NDGF Director, NORDUnet A/S
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