Block chain revival / recovery project

[altcoin.center]

Dear everyone,

I'm putting together a task force for the specific mission of developing ways to rescue/revive collapsing/collapsed block chains.

I'm rather new to the crypto coin scene but have a long background in data recovery and IT systems design & troubleshooting.

I'm looking for a handful of hard core developers willing to dedicate their brain time to come up with a functional and replicable method for reviving a block chain using, x number of block chain data files collected from separate computers.

I am aware of the challenges and ready to face them.

Anyone interested - please send me a PM or e-mail me at jyri@vertaisvaluutta.fi

Thanks!

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[DannyHamilton]

It is not clear to me what you are trying to do?

The Bitcoin Core wallet (and all full nodes for that matter) already build a blockchain using blockchain data from peers.

What is a "collapsing block chain" and how does it occur?  I don't understand.

[altcoin.center]

It is not clear to me what you are trying to do?

The Bitcoin Core wallet (and all full nodes for that matter) already build a blockchain using blockchain data from peers.

What is a "collapsing block chain" and how does it occur?  I don't understand.

Danny, thanks for the necessary request for clarification - I was way too concise and unclear in my original message.

While Bitcoin has been and is doing quite well in the sense that there doesn't seem to be a reason to worry that the chain would break down, many of the altcoins provide good (and sad) examples that things can go wrong if anything comes up that radically reduces the number of users/wallets able to connect with each other. Many block chains have been deadlocked into a situation where there are still a number of users out there, but none of them can synchronize with anyone anymore. It's just "no block source available" for all of them.

To give you couple of concrete examples, the Continuumcoin has just been broken down in the above manner. It was functional just few weeks ago, but now none of the existing users can find each other anymore. Another even more interesting example is provided by the Unum; it has the same problem with synchronizing, plus the PoS part ceased functioning after a while in a way that prevent it from starting again even if the users could find each other again.

Now while these problems have not (yet) faced Bitcoin, mainly thanks to the huge number of users, it's not a far fetched idea that something happens that stops intercontinental Internet traffic for prolonged periods of time. That, or any of the many other similar reasons could create a situation from which the chain would not be able to recover automatically.

In addition to data recovery, I also have lots of experience from the field of designing catastrophe tolerant communications systems etc. I'm involved in projects investigating emergency solutions such as temporarily replacing intercontinental Internet connections with HAM radio packet data. To make sure a full recovery of Bitcoin is available quickly should a disaster strike), I want to have a functional recovery plan created and thoroughly tested as soon as possible.

- Jyri
--
Altcoin.Center

[Dabs]

Bitcoin isn't going to have this kind of problem, so your proposal and solution is basically for all the other smaller alt-coins. But to think that bitcoin started small too.

Something else is killing the small coins. It couldn't be the value, as bitcoin was worthless back in 2009 and 2010.

[altcoin.center]

Bitcoin isn't going to have this kind of problem, so your proposal and solution is basically for all the other smaller alt-coins. But to think that bitcoin started small too.

How do you base this claim?

How would Bitcoin avoid from having trouble if something like a big CME (i.e. Carrington event) would take down the electric grids of whole continents for weeks or months, or if anything would disrupt the intercontinental net traffic?

Something else is killing the small coins. It couldn't be the value, as bitcoin was worthless back in 2009 and 2010.

There are many reasons to why many of the small coins are dying.

Quite often it is the fact that there are simply not enough users/wallets to keep the block chains up.

Bitcoin would experience similar trouble (although on a much bigger scale) should anything happen that prevents the users from reaching each other.

The only thing that makes Bitcoin different from smaller coins when it comes to it's tolerance against block chain breakage is the number of users out there.

I would like to hear your take on what would happen if the Internet was broken down to, say, 3-10 pieces that would not be able to talk to each other for even just a week.

- Jyri

[hhanh00]

I would like to hear your take on what would happen if the Internet was broken down to, say, 3-10 pieces that would not be able to talk to each other for even just a week.

Decentralized systems are very sensitive to network splits even for short duration of time. Let's say the Internet is split into two zones for a day. Users and miners in each region will continue to work without being aware of being isolated from each other. We would have two versions of the blockchain - which for all matter and purposes - are both valid.
It is called a split brain. http://en.wikipedia.org/wiki/Split-brain_(computing)

When the Internet recovers, the blockchain with the longest difficulty will prevail, making the other one orphan. All the transactions that happened in the orphan chain will be considered invalid causing loss to the merchants that sold goods.
Not to mention that double spends can happen at will in this scenario if someone has a connection to both networks.

In conclusion, the current design of Bitcoin does not cover the scenario of an Internet split. It goes beyond the need to recover a blockchain. There would be no good blockchain and recovering would require manually stitching the blockchain together. Is this what you want to tackle?

[DannyHamilton]

Users and miners in each region will continue to work without being aware of being isolated from each other.

This is incorrect. It would become quickly obvious that something significant had happened, since the average block time would double to 20 minutes (if the hash power split exactly in half).  If only a small portion of the hash power were isolated, then anyone on the isolated portion would likely see their average block time increase significantly.

We would have two versions of the blockchain - which for all matter and purposes - are both valid.

According to the protocol the longer one (the one with more total work) would be the valid one.  Anyone communicating on the isolated network with less hash power would have the "invalid" blockchain.  As long as they are aware of this, they can treat any transactions that they send or receive as unconfirmed until the network isolation has ended.

When the Internet recovers, the blockchain with the longest difficulty will prevail, making the other one orphan.

Correct.

All the transactions that happened in the orphan chain will be considered invalid causing loss to the merchants that sold goods.

This is incorrect.  The transactions that happened in the orphan chain will be considered unconfirmed.  It is extremely likely that they will confirm in the future blocks on the correct blockchain.  It is only if someone manages to accomplish a double spend on the "valid" blockchain while the network is split that some transactions from the isolated netowrk may become "invalid".  This would be difficult to accomplish since the attacker will be stuck on the isolated network.

Not to mention that double spends can happen at will in this scenario if someone has a connection to both networks.

If it is possible to connect to both networks, then it is possible to relay blocks between bloth networks.  Therefore, there won't be a split blockchain.

In conclusion, the current design of Bitcoin does not cover the scenario of an Internet split.

It would handle it reasonably well. Probably a lot better than many other global financial and communications services.

It goes beyond the need to recover a blockchain.

In what way?

There would be no good blockchain

Yes there would.

and recovering would require manually stitching the blockchain together.

No, it wouldn't.  Such a thing isn't even possible with a proof-of-work system.  

Is this what you want to tackle?

I hope not, because this would be a waste of time.

Note that Satoshi already answered most of this back in July 2010:

It's hard to imagine the Internet getting segmented airtight.  It would have to be a country deliberately and totally cutting itself off from the rest of the world.

Any node with access to both sides would automatically flow the block chain over, such as someone getting around the blockade with a dial-up modem or sat-phone.  It would only take one node to do it.  Anyone who wants to keep doing business would be motivated.

If the network is segmented and then recombines, any transactions in the shorter fork that were not also in the longer fork are released into the transaction pool again and are eligible to get into future blocks.  Their number of confirmations would start over.

If anyone took advantage of the segmentation to double-spend, such that there are different spends of the same money on each side, then the double-spends in the shorter fork lose out and go to 0/unconfirmed and stay that way.

It wouldn't be easy to take advantage of the segmentation to double-spend.  If it's impossible to communicate from one side to the other, how are you going to put a spend on each side?  If there is a way, then probably someone else is also using it to flow the block chain over.

You would usually know whether you're in the smaller segment.  For example, if your country cuts itself off from the rest of the world, the rest of the world is the larger segment.  If you're in the smaller segment, you should assume nothing is confirmed.

[Dimelord]

A very informative thread 

[Dabs]

I remember Jeff Garzik planning to put a node into space.

Here are some links:
http://www.coindesk.com/jeff-garzik-announces-partnership-launch-bitcoin-satellites-space/
http://bitcoinmagazine.com/14069/interview-jeff-garzik-bitcoin-space/
http://www.space.com/25626-bitcoins-satellites-deep-space-industries.html
http://www.wired.com/2013/12/bitcoin_space/

So, it seems we shouldn't have a problem... If large countries block bitcoin, they must do it intentionally. But with tor, and vpns, and all sorts of technologies available (bitcoin over firechat?) the blockchain will exist.

It's the alt-chains of alt-coins that are very small that will die.

I'm not a bitcoin "groupie" but honestly, there is no alt-coin (including the 2nd place one) that can do what bitcoin already is doing. I mean, sure, accept doges, lites, guns, greens, moners, whatevers-coin. But in the end it will go to BTC, and from there it can go to fiat.

The best analogy I can think of is that bitcoin is like a giant torrent with 10,000 seeders and 1 million leechers. You can't stop that. All you need is one or a few nodes to bypass whatever restriction you have, and the blockchain will "flow".

You would literally have to kill the internet to kill bitcoin.

But don't get me wrong Mr. AltCoin.Center, please do continue your project, while it may not be needed, it might be useful. That's what backups are for. Just in case.

[hhanh00]

Users and miners in each region will continue to work without being aware of being isolated from each other.

This is incorrect. It would become quickly obvious that something significant had happened, since the average block time would double to 20 minutes (if the hash power split exactly in half).  If only a small portion of the hash power were isolated, then anyone on the isolated portion would likely see their average block time increase significantly.

That's a good point. It's statistical though and using it as a programmatical way to determine a split would be wrong.
I suppose we need to frame the context of this scenario. There is a network split and no human decision can be taken while this happens. Highly improbable but otherwise we couldn't have such a split happening in the first place. Maybe a more probable scenario is if there is a bug that introduces a different behavior for half of the nodes.

We would have two versions of the blockchain - which for all matter and purposes - are both valid.

According to the protocol the longer one (the one with more total work) would be the valid one.  Anyone communicating on the isolated network with less hash power would have the "invalid" blockchain.  As long as they are aware of this, they can treat any transactions that they send or receive as unconfirmed until the network isolation has ended.

Yes - but they are not allowed to communicate.

All the transactions that happened in the orphan chain will be considered invalid causing loss to the merchants that sold goods.

This is incorrect.  The transactions that happened in the orphan chain will be considered unconfirmed.  It is extremely likely that they will confirm in the future blocks on the correct blockchain.  It is only if someone manages to accomplish a double spend on the "valid" blockchain while the network is split that some transactions from the isolated netowrk may become "invalid".  This would be difficult to accomplish since the attacker will be stuck on the isolated network.

Right. I forgot that orphaned transactions simply return to the mem pool.

Not to mention that double spends can happen at will in this scenario if someone has a connection to both networks.

If it is possible to connect to both networks, then it is possible to relay blocks between bloth networks.  Therefore, there won't be a split blockchain.

It could be possible for a mischievous person whereas the common person is unprepared especially if this is the result of a deliberate attack.

In conclusion, the current design of Bitcoin does not cover the scenario of an Internet split.

It would handle it reasonably well. Probably a lot better than many other global financial and communications services.

Hard to say. There are human factors to consider too.

It goes beyond the need to recover a blockchain.

In what way?

You would need to cherry pick the double spends.

There would be no good blockchain

Yes there would.

From a definition point of view, the longest chain is the good one. But this is still unpleasant to the victims of the double spends.

and recovering would require manually stitching the blockchain together.

No, it wouldn't.  Such a thing isn't even possible with a proof-of-work system.  

The system actually does it automatically by rerolling orphaned transactions. The manual part would be the result of customer complaints. People who are not happy with the result will call their merchants.

Is this what you want to tackle?

I hope not, because this would be a waste of time.

Note that Satoshi already answered most of this back in July 2010:

It's hard to imagine the Internet getting segmented airtight.  It would have to be a country deliberately and totally cutting itself off from the rest of the world.

Any node with access to both sides would automatically flow the block chain over, such as someone getting around the blockade with a dial-up modem or sat-phone.  It would only take one node to do it.  Anyone who wants to keep doing business would be motivated.

If the network is segmented and then recombines, any transactions in the shorter fork that were not also in the longer fork are released into the transaction pool again and are eligible to get into future blocks.  Their number of confirmations would start over.

If anyone took advantage of the segmentation to double-spend, such that there are different spends of the same money on each side, then the double-spends in the shorter fork lose out and go to 0/unconfirmed and stay that way.

It wouldn't be easy to take advantage of the segmentation to double-spend.  If it's impossible to communicate from one side to the other, how are you going to put a spend on each side?  If there is a way, then probably someone else is also using it to flow the block chain over.

You would usually know whether you're in the smaller segment.  For example, if your country cuts itself off from the rest of the world, the rest of the world is the larger segment.  If you're in the smaller segment, you should assume nothing is confirmed.

I don't see why it is so hard to do a double spend though. You don't have to be connected to both network. You need to know people who are and then ask them to broadcast the transaction for you.

[Dabs]

I don't see why it is so hard to do a double spend though. You don't have to be connected to both network. You need to know people who are and then ask them to broadcast the transaction for you.

That is not easy to do. Therefore, it is hard (or difficult). If it were easy, someone would be trying it already or doing it. Eventually, they will get caught because someone will have been defrauded. If it is a small enough incident, then it might go unnoticed.

In the bitcoin world, nothing is too small to be ignored.

Blockchain.info can see all double-spends right now. It happens, but is usually corrected over some time.

[DannyHamilton]

We would have two versions of the blockchain - which for all matter and purposes - are both valid.

According to the protocol the longer one (the one with more total work) would be the valid one.  Anyone communicating on the isolated network with less hash power would have the "invalid" blockchain.  As long as they are aware of this, they can treat any transactions that they send or receive as unconfirmed until the network isolation has ended.

Yes - but they are not allowed to communicate.

Correct, but it would almost certainly be obvious to the users that they are on an isolated subset of the internet.  Those that know they are isolated need to be aware that their transactions should be considered unconfirmed unless/until they are included in the blockchain that the rest of the world is using.  If the isolation lasts long enough for newly minted bitcoins to become spendable, then it would become necessary for those on the isolated network to stop using bitcoin altogether until their access to the global internet is restored.  If it's a situation where the subset of the network will be isolated for weeks or moths, it might be best for users stuck on the isolated sub-network to run their own altcoin.

Not to mention that double spends can happen at will in this scenario if someone has a connection to both networks.

If it is possible to connect to both networks, then it is possible to relay blocks between bloth networks.  Therefore, there won't be a split blockchain.

It could be possible for a mischievous person whereas the common person is unprepared especially if this is the result of a deliberate attack.

The "common person" doesn't need to be prepared.  As long as at least one technologically astute bitcoin user on the isolated network can figure out how to communicate with the rest of the world, they can relay solved blocks (and possibly even transactions) between the two networks.

It goes beyond the need to recover a blockchain.

In what way?

You would need to cherry pick the double spends.

Double spends would be VERY unlikely.  If they did occur, there would be no cherry picking.  The transactions that made it into the longer blockchain would be the successful ones, the others would be invalid.  All this is handled by catching up with the blockchain.

There would be no good blockchain

Yes there would.

From a definition point of view, the longest chain is the good one. But this is still unpleasant to the victims of the double spends.

Again double spends would be extremely unlikely. Any business that accepts transactions while they are isolated need to be aware that they are essentially accepting unconfirmed transactions, and are taking on the risks associated with that.

The manual part would be the result of customer complaints. People who are not happy with the result will call their merchants.

If those customers are double spending against the merchants, then they won't be calling the merchants complaining. The merchants will be calling them (and prosecuting them for fraud).

If the merchants are double spending against the customers, then the merchants aren't trustworthy to start with.  They'll have plenty of opportunities to rip off their customers without needing to wait around for this extremely unlikely internet isolation event to double spend.

I don't see why it is so hard to do a double spend though. You don't have to be connected to both network. You need to know people who are and then ask them to broadcast the transaction for you.

If communication can still be relayed between the two networks by an attacker, then blocks can be relayed by a technologically astute bitcoin user.  Anyone on the isolated network should consider any transactions "unconfirmed" and understand that accepting such transactions either requires an amount of trust in the payer or involves some risk of double-spend (like any unconfirmed transaction).

[hhanh00]

While I think that for the most part a country wide network split is unlikely to go undetected, I see two possible scenarios:
- A long lasting split. In this case, the smaller side has ample signs that it has become the orphan branch. Further transactions should be carried out considering the risk that they will become unconfirmed when the merge occurs.
- A movie scenario, where a hacker isolates a significant entity without them being aware of the situation in time for him to do his double spend.

Both are far fetched. Back to the original topic, the OP doesn't have to worry about the loss of the blockchain as it is already kept redundantly by thousand of nodes. If these all go away, it would be because Bitcoin has ceased to exist.
 

[Dabs]

There was a movie, Entrapment,

http://en.wikipedia.org/wiki/Entrapment_%28film%29
Entrapment is a 1999 American caper film directed by Jon Amiel and starring Sean Connery and Catherine Zeta-Jones.

The plot was not a double-spend, but it was a timing attack right before the year 2000 bug, where they steal 8 billion dollars.

As if this time, bitcoin's market cap is only 4 billion dollars. Still, some group might isolate one of the larger wallets / transaction processors / whatever and attempt to steal their 100,000 BTC. It's much easier to just open up an exchange and close it after you have 800,000 BTC.

[zvs]

A large quantity of monies, to be directed towards myself, would aid in this project

.. or I can sell you my 100,000 secondscoins.

[altcoin.center]

I would like to hear your take on what would happen if the Internet was broken down to, say, 3-10 pieces that would not be able to talk to each other for even just a week.

Decentralized systems are very sensitive to network splits even for short duration of time. Let's say the Internet is split into two zones for a day. Users and miners in each region will continue to work without being aware of being isolated from each other. We would have two versions of the blockchain - which for all matter and purposes - are both valid.
It is called a split brain. http://en.wikipedia.org/wiki/Split-brain_(computing)

When the Internet recovers, the blockchain with the longest difficulty will prevail, making the other one orphan. All the transactions that happened in the orphan chain will be considered invalid causing loss to the merchants that sold goods.
Not to mention that double spends can happen at will in this scenario if someone has a connection to both networks.

In conclusion, the current design of Bitcoin does not cover the scenario of an Internet split. It goes beyond the need to recover a blockchain. There would be no good blockchain and recovering would require manually stitching the blockchain together. Is this what you want to tackle?

Good analysis. The situation could easily get worse if the net was split to not just two but to an even larger number of individual "islands".

That is indeed the worst case scenario I also want to find a solution for.

The "reviving of a collapsed block chain" part is kind of a sub-problem of the major one you described above.

These two areas fo the problem have both similar and different problems to them.

I'm willing to put together a team with the required brainpower to come up with different scenarios, based on which we can arrange simulated block chain disasters and try to find functional solutions.

- Jyri

[altcoin.center]

While I think that for the most part a country wide network split is unlikely to go undetected, I see two possible scenarios:
- A long lasting split. In this case, the smaller side has ample signs that it has become the orphan branch. Further transactions should be carried out considering the risk that they will become unconfirmed when the merge occurs.
- A movie scenario, where a hacker isolates a significant entity without them being aware of the situation in time for him to do his double spend.

Both are far fetched. Back to the original topic, the OP doesn't have to worry about the loss of the blockchain as it is already kept redundantly by thousand of nodes. If these all go away, it would be because Bitcoin has ceased to exist.
 

It would indeed not be quite probable that the split would go unseen, although it would most probably take some time until everyone would know about it. Especially if the split would happen as a result of any major disaster (such as the Carrington event) the resulting fuzz would most probably create a situation in which any kind of communication and coordinated action would be rather challenging.

My guesstimate is, quite a large number of transactions would take place before all users would become aware of the situation. There's no information or education available regarding scenarios like this, so the reactions would be mixed. For anyone whose finances run mostly on Bitcoin (or any crypto coin) instead of fiat, the fact that he/she could not use her funds to make purchases would make the situation a lot tougher. While many may still use Bitcoin for more or less "just fun", there are many people and many areas who are quickly moving towards leaving fiat altogether.

I've been involved in a national level specialist team dealing with the scenario of a large CME knocking down the electric grids of the world. The fact almost no-one knows is that we have here in Finland the only electric delivery network in the world that has been protected against the induction currents that a Carrington event would create. It is a fact that the Earth will face a big blow eventually. When that happens, there is a large consensus among scientists and electric grid maintainers that whole continents will be without electricity for an indefinite amount of time. Fixing or replacing the blown up transformers could take months or even years. This is not considered as an unlikely but rather a certain scenario. What I'm saying here is not just my thoughts but the very clear conclusion of a top Finnish government level meeting 1,5 years ago where I was present myself.

the OP doesn't have to worry about the loss of the blockchain as it is already kept redundantly by thousand of nodes

Yes. However, getting the chain up based on the information on those nodes may not be quite straight-forward.

There are clearly two interconnected scenarios here: a big network split (which would create x number of separate, independent block chains) and a complete block chain breakdown created by the network being split into a very big number of relatively small "islands".

Thank you hhanh00 and everyone for the excellent comments and questions. Let's keep the discussion going. Whether or not each one of us considers the scenarios I'm presenting likely or not, this is an issue that needs to be addressed eventually anyways.

- Jyri

[altcoin.center]

Dear everyone,

thanks again for the comments and input!

Unfortunately, I'm not able to respond in further depth right now - I'm in a middle of an especially hectic period.

If anyone is interested and willing to participate in delving into this matter with me, please send me a PM or write to jyri@vertaisvaluutta.fi

I will be putting up a think tank specializing in analyzing and creating solutions for this as well as other crypto coin related vulnerabilities that have not yet been fully recognized an/or addressed.

My motivator to act (preferably before a disaster strikes) is my will to enhance Bitcoin's (and the crypto coin technology in general) chances of replacing the fiat currencies. In order for that to happen, the technology has to be such that it can cope with unexpected situations as well.

- Jyri

[Nxtblg]

I've been involved in a national level specialist team dealing with the scenario of a large CME knocking down the electric grids of the world. The fact almost no-one knows is that we have here in Finland the only electric delivery network in the world that has been protected against the induction currents that a Carrington event would create. It is a fact that the Earth will face a big blow eventually. When that happens, there is a large consensus among scientists and electric grid maintainers that whole continents will be without electricity for an indefinite amount of time. Fixing or replacing the blown up transformers could take months or even years. This is not considered as an unlikely but rather a certain scenario. What I'm saying here is not just my thoughts but the very clear conclusion of a top Finnish government level meeting 1,5 years ago where I was present myself.- Jyri

Right; I figured as much. Around here, the people who'd be most open to your plan are known as "preppers." They're people who have no trouble imagining the collapse of the entire Internet.

If you're of that mind, "how to re-establish a crypto network if the entire Internet goes down?" is a fascinating challenge. I know I'm drifting into longity-long-shot territory here, but Bitcoin or an alt re-establishing itself after a breakdown of the entire Internet would be a real history-making use case for cryptocurrency. Yes, I said "history-making."

[altcoin.center]

I've been involved in a national level specialist team dealing with the scenario of a large CME knocking down the electric grids of the world. The fact almost no-one knows is that we have here in Finland the only electric delivery network in the world that has been protected against the induction currents that a Carrington event would create. It is a fact that the Earth will face a big blow eventually. When that happens, there is a large consensus among scientists and electric grid maintainers that whole continents will be without electricity for an indefinite amount of time. Fixing or replacing the blown up transformers could take months or even years. This is not considered as an unlikely but rather a certain scenario. What I'm saying here is not just my thoughts but the very clear conclusion of a top Finnish government level meeting 1,5 years ago where I was present myself.- Jyri

Right; I figured as much. Around here, the people who'd be most open to your plan are known as "preppers." They're people who have no trouble imagining the collapse of the entire Internet.

If you're of that mind, "how to re-establish a crypto network if the entire Internet goes down?" is a fascinating challenge. I know I'm drifting into longity-long-shot territory here, but Bitcoin or an alt re-establishing itself after a breakdown of the entire Internet would be a real history-making use case for cryptocurrency. Yes, I said "history-making."

Yes, "preppers" is a familiar term for me and although I don't exactly count myself to be part of the hard core posse, I have indeed spent quite a lot of thinking energy to ponder upon the possible scenarios.

Even though Carrington's event is just one of the potential reasons for a world-scale breakdown of communications networks, it is (according to not just preppers but many main stream scientists) the most possible reason.

Back in 1859 when the latest big Carrington occured, "Telegraph systems all over Europe and North America failed, in some cases giving telegraph operators electric shocks. Telegraph pylons threw sparks. Some telegraph systems continued to send and receive messages despite having been disconnected from their power supplies." (https://en.wikipedia.org/wiki/Solar_storm_of_1859)

Back then telegram lines were the only "grid" out there. If an event of similar scale took place now, the effects would be way more significant.

While the TCP/IP protocol was particularly designed to be "nuclear war proof", this original aspect of redundancy has been long forgotten. There are a number of submarine telecommunication cables out there (http://www.submarinecablemap.com/) so even if several of them were lost, the traffic could (at least in theory) be rather easily rerouted. Also, fiber optic cables are not directly affected by the fluctuations of the geomagnetic caused by major solar eruptions. However, if the electric grid itself was to go down from large areas for a prolonged period of time, it would have an impact on the data traffic as well.

The past few decades have been relatively calm and stable, but it would be living in an illusion to think that nothing can happen that would take the Net down - or break it into pieces.

It's another matter altogether, would the survival of crypto currency block chains matter in a scenario that would be directly life-threatening in many other ways.

Even so, I do consider the block chain issue worth further investigation - and action.

- Jyri