
DagCoin: a cryptocurrency without blocks - gwern
https://bitslog.wordpress.com/2015/09/11/dagcoin/
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pash
The author's goal for this design seems to be to increase mining
decentralization, but there's another big advantage to a blockless graphical
ledger over a blockchain. By attaching proof-of-work to each transaction
rather than to a block of multiple transactions, a blockless scheme asks
miners to answer a simple cost-benefit question: does the payoff to putting
the transaction in the ledger (in transaction fees and seignorage) exceed its
cost (in hashing resources)?

Particularly when seignorage is zero, so that a miner's only compensation for
providing proof-of-work to a transaction is the fee it offers, this eliminates
a free-rider problem created by blocks in a scheme like Bitcoin's; as long as
you can include as many transactions in a block as you like, the cost of
including another one is nil, and so miners have an incentive to include every
transaction that pays a non-zero fee, no matter how small [0]. That means the
equilibrium price of putting a transaction into Bitcoin's blockchain, for
example, may never rise much above zero. That's a real problem for the long-
term security of the Bitcoin blockchain.

Per-transaction proof-of-work eliminates that problem by making both the cost
and reward of adding a transaction to the ledger a function of the properties
of each transaction, rather than of an arbitrary aggregate of transactions.

0\. This isn't true if there is a binding limit on the size of blocks, as
there is now in the Bitcoin protocol. But a wholly arbitrary block-size limit
is a terrible solution to this problem because it is unresponsive to economic
factors. It may be possible that a non-zero equilibrium price of transacting
could arise in response to other constraints (like the risk of "orphaning" a
large block due to the increased time it takes to propagate around the
network), as some people have argued in the course of Bitcoin's ongoing block-
size war.

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madmod
Could a DAG chain be able to solve the latency issue for cross planetary
currency with several root "branches" for different planets?

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DonHopkins
We need a cryptocurrency that doesn't cause so much coal to be burned.

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pellmellism
The more power consumed, the stronger it is. A cheap chain is a weak chain

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DonHopkins
How about solar batteries with built-in "greencoin" cryptocurrency mining
circuitry, that generate electricity instead of heat as a by-product? ;)

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DennisP
What does it mean for a transaction to reference previous transactions? Is it
just listing them, rather than using them as inputs?

> If two conflicting transactions appear, as more transactions are added to
> the DAG-chain, the number of confirmations of one of the two will increase,
> but the other will not

Is that just because people go with whichever has the most references and/or
proof-of-work so far?

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chrispeel
I like the basic idea of combining transactions and blocks.

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SDLerner
Take a look at IOTA Tangle. They're are developing this concept further into a
IoT payment network. S.L.

