The ones that *could* pay non-mining full nodes are miners/pools, by outsourcing transaction selection using a different PoW. By doing so they could buy proof-of-uncensored-selection and proof-of-goodwill for a small fee.
We would allow full nodes to generate and broadcast a template block which:
* Does not contain a valid header yet
* Contains the transaction selection
* Contains a coinbase output with a predetermined part of the block reward (say 0.5%) to themselves
* Contains a nonce for PoW of a predetermined currently ASIC resistant hash function behind a OP_RETURN.
The template with the highest PoW since the last block would be leading. A miner/pool can then choose to use this instead of their own, adding the rest of the reward and the SHA nonce themselves. That way they would set up a competition among full nodes.
This would of course be voluntary but provable, so maybe in a pool's interest to do this via naming and shaming.
Tomas
bitcrust
On Wed, May 3, 2017, at 23:43, Ben Thompson via bitcoin-dev wrote:
I feel like this would be pointless as the vast majority of users would likely download the blockchain from a node that was not enforcing a tip requirement as it would seem like unnecessary cost as in protocols such as BitTorrent there is no such tips in sharing files and the blockchain distribution is in eccense the same thing. However perhaps I am underestimating the generosity of node operators but I feel that adding a cost to the blockchain (assuming that all users add a tip requirement) would lead to centralisation.
- Full nodes advertise a bitcoin address. Users that need to download the block chain from that node can be encouraged to send a tip to the peers that served them (by % served). Recommended tip of 10mbit should be fine.
- A full nodes can *require* a tip to download the blockchain. If they do, users that don't specify a tip cannot use them.
CONS:
For some people, this may represent a barrier to hosting their own full node. After all, if you have to pay $15 just to get a copy of the blockchain, that just adds to the already expensive prospect of hosting a full node.
PROS:
As long as you manage to stay online, you should get your money back and more. This is the an incentive for quality, long term hosting.
In the long term, this should cause stable nodes to stick around longer. It also discourages "installation spam" attacks on the network.
Fees for other node operations can be considered if this is successful.