Why bitcoin cannot grow past 4 million users

[SgtSpike]

Excellent explanation creighto, thank you.

So theoretically, as bitcoin expands, we'll see fewer and fewer people solo mining, more and more people pool mining, and more and more people connecting to the pool servers as nodes to verify blocks/transactions for their thin clients.  I can see this working...

How difficult would it be to implement a new "thin" client?  Or does one already exist?

[wareen]

Shouldn't we start thinking about and planning for these scenarios, rather than waiting until they are upon us?

I'd say this scenario is already upon us when it comes to smartphone clients - they will be the driving force towards a very lightweight (in terms of diskspace, processing power and bandwidth requirement) yet secure client for the Bitcoin network.

As such a smartphone client seems to be considered to be an important step for the short to medium term successfulness of Bitcoin by quite a few people I would not worry about the diskspace requirements for the mainline client. The techniques to make a lean and secure client for smartphones will probably be useful to the mainline client as well and they will probably be developed soon.

[Rob P.]

Thanks creighto, excellent post.

The take away is that there will continue to be innovation in the current Bitcoin network/software.  As such, these issues can and will be addressed as time goes on.  If you don't believe that will happen, then you shouldn't be using Bitcoin.

[SgtSpike]

wareen - Good points regarding the smartphone.  The market is there for a smartphone client, it's just a matter of someone actually sitting down and coding one.

Rob P - I do believe the issues will be addressed, but that doesn't mean we shouldn't start addressing them.  After all, if now is not the time to address the issues, when will that time be?  Are you going to wait until people start hitting their monthly download caps because they had to download the entire blockchain?  In my opinion, we should be working on implementing a thin client now, not waiting until it becomes a problem and it may be too late to implement an effective solution fast enough to prevent people being turned away from bitcoins.

[MoonShadow]

Excellent explanation creighto, thank you.

So theoretically, as bitcoin expands, we'll see fewer and fewer people solo mining, more and more people pool mining, and more and more people connecting to the pool servers as nodes to verify blocks/transactions for their thin clients.  I can see this working...

Personally, I predict that trusted peer services will spring up, eventually, with the promise that transactions sent from paying users' clients will continue to be processed by the "bitcoin bank's" own pool and/or datacenter for free, even if it might take some time.  This might also become a privilage of pool contribution.

How difficult would it be to implement a new "thin" client?  Or does one already exist?

I'm not a programmer, but my understanding is that it's already part of the protocol, but isn't yet included in the standard client for several reasons.  Not the least of which is the lack of urgency as compared to other concerns, such as encryption of the wallet.dat file.

[MoonShadow]

wareen - Good points regarding the smartphone.  The market is there for a smartphone client, it's just a matter of someone actually sitting down and coding one.

Rob P - I do believe the issues will be addressed, but that doesn't mean we shouldn't start addressing them.  After all, if now is not the time to address the issues, when will that time be?  Are you going to wait until people start hitting their monthly download caps because they had to download the entire blockchain?  In my opinion, we should be working on implementing a thin client now, not waiting until it becomes a problem and it may be too late to implement an effective solution fast enough to prevent people being turned away from bitcoins.

The BitcoinJ project is an attempt to do just that in Java for Android.  If you have the skillset, feel free to participate.

[SgtSpike]

wareen - Good points regarding the smartphone.  The market is there for a smartphone client, it's just a matter of someone actually sitting down and coding one.

Rob P - I do believe the issues will be addressed, but that doesn't mean we shouldn't start addressing them.  After all, if now is not the time to address the issues, when will that time be?  Are you going to wait until people start hitting their monthly download caps because they had to download the entire blockchain?  In my opinion, we should be working on implementing a thin client now, not waiting until it becomes a problem and it may be too late to implement an effective solution fast enough to prevent people being turned away from bitcoins.

The BitcoinJ project is an attempt to do just that in Java for Android.  If you have the skillset, feel free to participate.

Glad to hear it!  Unfortunately, my skills in Java are a bit rusty/limited, so I will sit that one out.

[theymos]

The lightweight client code is actually mostly working in Bitcoin. Search the code for "fClient".

[Dusty]

The lightweight client code is actually mostly working in Bitcoin. Search the code for "fClient".

I can't find any reference to "fClient" on the bitcoinj sources, can you please elaborate?

[theymos]

The Bitcoin code, not BitcoinJ.

[unclescrooge]

I started this thread on another forum, but thought I'd post it here as well...  I believe that bitcoin, in its current form, cannot grow past about 4 million users, give or take a few million.

http://bitcoinforums.net/index.php?threads/the-blockchain-a-blessing-or-a-flaw.68/

Wow, that's... scary.

I think the bottleneck here is download speeds. Computer storage capacities will increase at at least close to the pace of Bitcoin, and I don't mind dedicating some hard drive space. But internet speeds are dependent on big money-hungry companies, for the most part, and that's what worries me. What we really need is a fast Bitcoin-funded internet service; hopefully that will happen before network congestion becomes a major problem.

Ewallet

[Jack of Diamonds]

That estimate is ridiculous. There will never be 7 billion people using any single internet service.

In fact only 2 billion people, or 28% of the world's population even has access to the internet (and only ~1.2 billion through home connections).

Facebook is the largest online community/service ever and it has about 500 million users. Paypal is the largest payment processor and it only has about 20-40 million active users.

[Basiley]

as long as FaceBook mind develop own kind of money we're all doomed

[Alex Beckenham]

There will never be 7 billion people using any single internet service.

Not even in 2140?

[Jack of Diamonds]

Not even in 2140?

Probably not, according to the UN there will be about 9 to 14 billion people alive by then, the vast majority living in poor countries. Population growth will be severely limited by resources in 2050-2080 as well so it wont grow exponentially.

http://www.un.org/esa/population/publications/longrange2/WorldPop2300final.pdf

Even in the extreme scenario (14-15 billion by 2140) that'd mean half of the world's population would have internet connection or use bitcoin.

Now the population is at about 6.9 billion, and the most popular web service has only 500m users (~7% of world population). That means 93% of people in the world have no idea what Facebook is or haven't used it.

[triforcelink]

What about having services which allow people to access their wallets remotely? If a datacenter stores the blockchain and handles all the transactions then the end user wont have to worry about losing their wallet, storing the blockchain, etc. the end user simply has to be able to initiate the commands and see the results. Sure this may appear to be less decentralized, but look at the internet, not everyone hosts their own website, not everyone has their own dns server.

[Dusty]

What about having services which allow people to access their wallets remotely?

Someone already tougth of this entirely new concept and put it to work: you can find it on the net, it's called "bank" ;-)

[triforcelink]

What about having services which allow people to access their wallets remotely?

Someone already tougth of this entirely new concept and put it to work: you can find it on the net, it's called "bank" ;-)

so whats up with all the worry about people not being able to stash away their personal block chains?

[MoonShadow]

What about having services which allow people to access their wallets remotely? If a datacenter stores the blockchain and handles all the transactions then the end user wont have to worry about losing their wallet, storing the blockchain, etc. the end user simply has to be able to initiate the commands and see the results. Sure this may appear to be less decentralized, but look at the internet, not everyone hosts their own website, not everyone has their own dns server.

I addressed this elsewere...

http://forum.bitcoin.org/index.php?topic=16764.msg219594#msg219594

So if we assume the OP assumptions are correct (I don't, because I understand the system better than he) then the worst case scenario is that bitcoin is limited to 4 million nodes, not users.  Surely the wealthy (or otherwise distrusting) might choose to run their own nodes, which might be costly in 20 years, but that is not a real limitation on the average Joe.

[Alex Beckenham]

What about having services which allow people to access their wallets remotely?

Someone already tougth of this entirely new concept and put it to work: you can find it on the net, it's called "bank" ;-)

And over the last 12 hours we've just seen how much you can rely on a 'bank'.

(Not much)