Topic: A Scalability Roadmap (Read 14845 times)

And Greg Maxwell said he was going to produce soon a BIP (?) on this promising flexcap proposal. Can't wait to see that.

i don't see why you guys don't work on researching blockrope.

Technically, they are both potentially proposals for core.

BIP-100 isn't actually being pushed, I think, it is just a suggestion.

There is no proposal that is accepted by all core devs.

If you haven't been keeping up, Gavin has a BIP for Bitcoin XT and there is another BIP for Bitcoin Core.

So both clients have a proposal in progress.

http://gtf.org/garzik/bitcoin/BIP100-blocksizechangeproposal.pdf

https://github.com/gavinandresen/bitcoinxt/tree/blocksize_fork

I'm amazed this thread was started over 8 months ago!  I am glad to see Gavin forging ahead, and I hope the other CoreDevs eventually come around and will lend their support to the chain with larger blocks.  They may not ever agree it was the best strategic move, but Bitcoin has many other fronts that need work and development, and their extensive knowledge of crypto-systems will be needed moving forward.  I think the "keep-it-small" group is correct, in a very technical sense.  But Bitcoin is more than just technology, it is also a political movement that needs broad support to reach is maximum effect, and I think that Gavin is more savvy, by far, to that side of things than most of the other devs.  Bitcoin does not necessarily need to be designed to withstand large-scale government-style attack.  It could be designed so, and that threat of 'could' alone is a powerful deterrent.  Yes, we have the technology to hide a blocks in tor, with everything encrypted and miners are in secret locations, etc, etc, etc.  But the more widely Bitcoin moves into the main stream, the less such techniques will be required.  Even proof-of-work mining may be altered.  It is a means to a secure system, not an end.  If more efficient ways of having a secure system are devised, perhaps the amount energy used to secure the chain can be safely reduced.

Bitcoin is not secure in the abstract, it is secure against certain threats from certain directions.  As the threat model changes, the security engineering of Bitcoin can, and should, change as well.  Reaching 'mass adoption' quickly is, I believe, a valid way of making Bitcoin more secure.  Not via a 'technical' approach, but through a 'social' one.

Is there some way you think Gavin's proposal is superior to BIP 100?

The game theory idea that miners will keep including more transactions in blocks, which is in each miners own selfish interest but against the interests of a whole industry, is not just a theory, but is happening today in many commodity markets like oil.

http://www.docdroid.net/14gw5/oil.pdf.html

This will eventually destroy the mining industry if the blocksize is too large.  The move by Gavin to push ahead with 8GB blocks at this point is very dangerous.  Who knows what demand will be like in the 2030s?

Thanks good read, i have gotten to see hes perspective on the transaction growth if bitcoin want to be ready for the future where a complete nation can make one transaction a day and the system would still keep up,
now thats the power of a good vision for the future.

I'm siding with Gavins proposal all day long. We certainly need the changes he is proposing. They were running a stress test today on the blockchain and it proved that the core needs helps in a number of ways.

Looks like we have multiple "roadmaps" or proposals to consider now and much more testing ahead, starting with today. Peter Todd had an interesting write up concerning todays stress test - https://gist.github.com/petertodd/8e87c782bdf342ef18fb

We Have Garzik's BIP 100 - http://gtf.org/garzik/bitcoin/BIP100-blocksizechangeproposal.pdf
Gavin's Proposal - https://github.com/gavinandresen/bitcoinxt/commit/821e223ccc4c8ab967399371761718f1015c766b

A few other proposals that are being discussed and miners looking to form consensus with developers -






Appears 8  may be a lucky number but only after more discussion and testing is done. It isn't clear the exact specifics of which proposal will be selected. From reviewing the 2 above I have concerns with both of them.

So do we have a roadmap, or is more research needed?

Gavin has now written part 2, Blocksize economics
https://bitcoinfoundation.org/2014/10/blocksize-economics/

New thread
https://bitcointalk.org/index.php?topic=825601.new#new

Yes they can make fake transactions to fill blocks. That would partially shut some miners with small bandwidth. The occasional very large blocks might cause the smaller blocks to not propagate and thus get orphaned. The low bandwidth miners would need to make up for it by increasing their hashrate if they have other advantages like cheap power or government subsidies. It's just another competition vector.

Sounds like an irrational fear to me. Big centralized miners couldn't care less about little miners. Little miners are insignificant. And what are these big centralized miners going to use to fill up these huge blocks? Fake transactions? That makes no sense. Real transactions? Then there's a real need for such huge block sizes.

The costs of entering the market of mining grow with the number of transaction and the hashing power of the network, but there are ways to collaborate that lower the cost of entering in the mining sector (pools).
The pool hub is the only in need to pump out the blocks, the miners do not need a large bandwidth to start mining.

It is true a 51% pool could drop other miners blocks, but it would lose a lot of support from the associated miners if it did so, because it would be detrimental to the health of the network long term.
A large miner could invest heavily and gain the 51% and make an attack (just dropping others blocks), but he would jeopardize its investment in doing so, because it would become the controller and the central point of failure of the network. Essentially it would paint a big target on its back for law enforcement and assorted nasties. I bet, when someone make an investment on the order of $180M (plus assorted ancillary costs) a need a 150 MW power line he consult lawyers about its business plan.

Expanding markets do attract new entrants in general, but in the case of Bitcoin, it also increases the barrier to entry, because each participant must be capable of handling all Bitcoin transactions.  The cost to the network of processing a transaction grows at least as quickly as the number of miners (assuming constant technology for simplicity).

Also, you're right that in a reasonably decentralised environment, large mining companies cannot exclude competitors through voluntary means alone.  However, with Bitcoin, there is the 50% threshold to worry about too, something absent in most markets.  In a typical free-market, if an entity accumulates more than 50% of the business then they'll keep that monopoly if and only if they continue to outperform their competition.  This entity will begin to lose market-share if they even cease to innovate, let alone try to abuse their position.  With Bitcoin, there are different incentives involved and a monopolist may well stand to gain from excluding small miners by dropping their blocks.

Mining will need to be self sufficient using just fees and without block rewards in the long run.
So, if we take the capability of VISA network as a goal, we need at least 0.01 $ fee per transaction to give the miners the same amount of money they get today. And the minimum block size to be able to do so is very large to accommodate at least 4.000 transactions/second (and VISA process 8.000 transactions per second during high traffic days).

Decentralization is the main goal, because it make the network censor resistant.
But what make possible to maintain decentralization is openness. Anyone, no matter who, can connect and join the network if he has the resources to do so.

Miners need to distribute their block faster first to other miners and then to other nodes. If they distribute their block to other miners first, these miners will start to mine the next block earlier. If a miner was able to flash his blocks to the core nodes of network instantly (E.G. broadcast by DVB-T), but not to the (hash rate) majority of the miners, his ability to communicate would not count a lot, because the core nodes would be exposed to a longer competing chain shortly after. The core nodes just need to download the new blocks from the miners and/or offer them to other core nodes to be able to check the blocks, they don't mine, so they don't need the new blocks in a matter of seconds after they are discovered.
As with many different P2P networks, they work better if different nodes organize themselves in different ways/strata.

Just now, miners (usually miners pools) make large investments in mining rigs and related HW, SW, labor, power and real estate. They can afford to buy enough bandwidth to disperse blocks between themselves in a matter of seconds. More so if there is a Reverse lookup table  and they just need to exchange mainly references to the Tx included and not the actual data.

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The rationale to grow faster now with the block size exist because when the block reward will be halved, the revenues of the miners will halve if the price do not at least double.
The single fees can not grow x100 to compensate the reduction of the reward in just few months. They must be able to grow in number to compensate the diminishing reward, not become more costly for the consumer.
At least there must be room to allow this grow to happen.

Now a transaction cost 18$ (miners income = reward + fees). It is obviously impossible to sustain this costs if it came out directly from the users.
https://blockchain.info/it/charts/cost-per-transaction

The network must be able to manage the 1000 times the current transactions to bring the cost down to 1.8 cents from 18 $. Currently we have around 300 KB blocks, so the block size should increase to 300 MB (at least). Make it 600 MB to bring it down to 1 cent and 1 GB to compete with VISA.

The network will grow proportionally faster now than in the future, when it will have taken larger part of the market of payments. The curve will be something resembling an asymptotic curve to some level (E.G. 10x VISA) or linear increase (VISA + x transactions/year). But the steepest part will happen now and in the near future (4-6 years and no more).

Blocks don't just magically grow in size for no reason.

Blocks get larger because of an increased demand for Bitcoin transactions.

A larger number of bitcoin transactions means more aggregate fee revenue, which means as the block size grows the miners are competing for an expanding market.

Expanding markets attract new entrants into the market, and in the case of Bitcoin mining there is no way for incumbents to exclude competitors who produce valid proof of work.

Because I believe these trends are dependent on the negligible cost of handling blocks, costs which will become significant soon enough if the block-size growth trend continues unabated.