https://kycnot.me/

Take your pick. I'd recommend Bisq or AgoraDesk. A quick look shows that they both offer GBP pairs.

5 characters will be fairly easily brute forcible using btcrecover.

First of all, tell us what it is exactly are you trying to brute force? It sounds like it is a passphrase extension to a seed phrase?

Secondly, do you know an address from this wallet, preferably the first one? If you do, it will be much easier to brute force, but it is still possible if you don't by using an address database.

btcrecover has some fairly straightforward instructions on the website, but I'm happy to guide you through setting it up if you get stuck.

Then just enable RBF on all your transactions.

There really is no reason not to. There is plenty of good wallet software out there which supports it. Given that opt in RBF has existed for 8 years, if your wallet software doesn't support it then it's time to find new wallet software. If you are in a hurry you don't have to massively overpay since you can just bump your fee if the mempool suddenly fills or there is a long delay to the next block. If you are not in hurry you can set a low fee and bump it at a later date if circumstances change and you still aren't confirmed.

With full RBF continuing to gain traction, if you are still using wallet software which does not allow you to replace transactions easily then you are going to be left behind.

Age used to be an important factor, back when the vast majority of transactions did not pay any fee. The more confirmations an input had before you spent it, then the higher the priority given to that transaction. The other factors taken in to account were the amount being spent (higher amounts had a higher priority), and the size of the transaction (smaller transactions had a higher priority).

But of course none of that is relevant any more, and miners prioritize transactions solely on the fee rate that they pay.

It's certainly possible - miners are free to include or exclude any transactions they wish.

However, you shouldn't think of mining pools as a single entity. Large mining pools are a collection of miners belonging to hundreds or even thousands of different entities, who pool their resources in the same pool in order to smooth out their incomes. If a pool operator announced they were going to start selectively censoring some transactions, then many of the miners on that pool would simply switch to a different pool.

Further to this, let's say a pool did start only accepting transactions which were broadcasted through their own platform or paid a private fee. They would be missing out on the fees from the vast majority of transaction in the mempool, and so anyone mining on that pool would receive less income. There would be no incentive for miners to stay on that pool when they could switch to another pool and receive more income instead.

A block must contain a coinbase transaction, but beyond that it can be empty.

This is wrong. The block subsidy is currently 6.25 BTC, with the average fees being collecting from a block somewhere between 0.1 - 0.5 BTC.

Your terminology is also wrong. Empty blocks are not orphans.

Perhaps stop taking "advice" from random strangers on Twitter.

Yes, it is blatantly a scam.

The domain name bitcoin.org was registered two months before the whitepaper was released.

I had always assumed it was a natural development from Szabo's bit gold, with the word coin chosen instead to reflect that fact it is a peer to peer currency.

I think these are worse. Checks depend on the authority of a centralized third party to be cashed in. Note or bill could work, but these words are not universal across the English speaking world. Coin is, on the other hand.

eCash already existed - https://en.wikipedia.org/wiki/Ecash

Satoshi was aware of the possible need to transition to a different signature scheme in the future, which would make "sec" a poor choice - https://bitcointalk.org/index.php?topic=202.msg2133#msg2133

I don't think either of those scenarios would be accurate. As I said above 11.7 sats/vbyte was 90 MvB from the tip. If the mempool stayed the same size as in no new transactions were broadcast, then you would hit that level in about 15 hours, which is far less than 3-7 days. Similarly, if the mempool stayed the same size as in every block which was found was replaced by the same weight of new transactions paying the same fee, then we would never hit 11.7 sats/vbyte because the mempool would never empty.

Every fee estimator has its own method. Some are better than others. Some simply place your transaction within x MvB from the tip, while others pay attention to recent trends, whether the mempool is filling or emptying, incoming transactions over the last x hours, variance in the hashrate, and so forth.

The static and mempool fee from Electrum requires no estimation. You simply pick either a flat fee or the set number of MvB from the tip. The code for the ETA fee on the other hand can be found here: https://github.com/spesmilo/electrum/blob/fda408e4e47f3093cf8da6713174bfc1cb5bac63/electrum/simple_config.py#L423

The only stipulation is that parent transactions come before child transactions. Usually this rule is irrelevant, because the vast majority of transactions have their parent transactions already confirmed in previous blocks. The time this does apply is in the case of CPFP or any other situation where a transaction spending an unconfirmed output confirms in the same block as its parent. In these cases, the parent(s) must be earlier in the block than the child(ren).

Having said that, although miners are otherwise free to order transactions any way they like, transactions are generally ordered in terms of fee rate, from highest to lowest, as the software building the candidate block simply picks transactions by their fee rate, from highest to lowest.

It isn't.

What you are missing is that you are making the assumption the mempool size remains the same.

We cannot predict what the mempool will do. We cannot predict how many new transactions are going to be broadcast, how large those transactions are going to be, or what fee those transaction will pay. We also cannot predict whether we will find 10 blocks in the next hour or 0 blocks in the next hour. As such, every fee estimation is exactly that - an estimation.

Having said all that, an estimation of 11.7 sats/vbyte for 3 days is on the low side, since we've got over 90 MvB of unconfirmed transactions above this level already in the mempool, even without taking in to account any new transactions. For 3 days right now I would probably go somewhere around 16 sats/vybte which is about 20 MvB from the tip, but it's still just an educated guess.

The thing to do is to make sure you enable RBF on all your transactions. That way if it gets stuck, you can easily bump the fee higher.

I have been one of the most vocal opponents of NFTs and other such worthless crap. However, who am I to say that someone else's use case of bitcoin is wrong, and preventing them from using bitcoin in this way? What's to stop someone else coming out and saying that my use case of bitcoin is wrong, and trying to do the same thing to me?

This of course ignores the fact that even if you banned this particular method for embedding data in the blockchain, then there are other ways to embed data in the blockchain that we cannot ban, such as within signatures.

As far as I understand, the reason median is used is because it guarantees that the lower bound never goes backwards. With each new block found it either advances, or doesn't change. If the mean was used, then there is the possibility that the minimum timestamp could move backwards.

Thanks to an off-by-one error, not only is the last block of one epoch different to the first block of the next epoch, but actually the time it takes to mine the first block of every epoch is not taken in to account whatsoever when calculating the difficulty.

Miners are free to use any algorithm they like in order to choose which transactions to include in their candidate blocks.

In general however, then yes, miners simply prioritize the transactions in their mempool which have the highest fee rate. There are a few exceptions to this - for example mining pools will also include their own transactions with very low fees, Binance pool includes transactions made by the Binance exchange with low fees, they may include transactions they have been paid privately to include, and so on. However, these types of transactions usually only make a small handful of the total number in the block, with the vast majority of transactions simply being prioritized based on their fee rate.

Binance is centralized trash and not really peer to peer at all, as already discussed. Bisq does indeed offer cash trades. Using Bisq is much safer than a centralized exchange provided you take standard precautions and use their in built escrow.

Here's how it would work.

For this, it is important to know that block timestamps are governed by a lower bound of the median timestamp of the last 11 blocks plus one second, and an upper bound of 2 hours in the future.

Let's say I am a miner with a small percentage of the hashrate. I mine my own competing chain in secret. It takes me longer than 10 minutes per block, but that's ok. Let's start at the beginning of the next difficulty epoch for the sake of this example.

I mine a block and give it time x. The next block that I mine, I give time x+1 second. The block after that, x+2 seconds. And so on, for 2,015 blocks, up to x+2,014 seconds. The last block of the difficulty epoch I give a timestamp of the current time.

Let's say it took me 60 days to mine those 2,016 blocks. The difficulty now drops by a factor of 4, the maximum allowable change in one retarget. I keep mining, but now consider the timestamps of the last 11 blocks I just found. The last block I just found has a timestamp of the current time, but the 10 blocks before that all have a timestamp of x plus a few seconds, which is now 60 days ago. If we take the median of those 11 blocks, then we still have a timestamp which is 60 days ago.

So I can keep mining blocks, and continue giving all the blocks I find a timestamp of x+1 more second, which is 60 days ago. I do this for another 2,015 blocks, and then the last block of the epoch I set to the current time. This time, let's say it took me 15 days to mine those blocks, since the difficulty was lowered by a factor of 4. However, the first block of these 2,016 blocks still has a timestamp of x+some seconds, which is now 75 days ago. So the protocol thinks it took me 75 days to mine these 2,016 blocks, and the difficulty is lowered by another factor of 4. Now consider again the timestamp of the last 11 blocks. The last block has a timestamp of the current time, and the 10 before that have a timestamp of 75 days ago. The median timestamp is 75 days ago.

So I repeat the process again. Every difficulty epoch I mine 2,015 blocks incrementing the time by 1 second only from the initial value of x all those days ago, and then the last block at the current time. This is all within the rules set out above. Each time we hit a retargeting, the protocol thinks it has taken me longer and longer to find the last 2,016 blocks, and the difficulty drops by a factor of 4 each time. And each time, the median timestamp of my last 11 blocks never moves by more than a few seconds.

Very quickly I can drop the difficulty to 1 and keep it there. I can churn out a block a second for as long as I want. If the rule was to follow the longest chain, then I can broadcast this chain I have been mining in secret and successfully take over the entire network indefinitely.

Binance peer to peer is not peer to peer at all. It is peer to Binance. It is completely centralized, and owned and operated by Binance. As such, you have absolutely zero security since you hand your coins over to Binance like you do with any other centralized exchange, and you have absolutely zero privacy, since Binance track and record every trade and transaction that you make. It is the worst possible choice for peer to peer trading.

What about the literally billions of physical trades which happen every single day around the world without issue? Why is trading bitcoin any more risky than buying some piece of electronics or taking money out of an ATM?

You don't need to. Use a platform like Bisq which has a built in escrow.

What nonsense is this? Trading peer to peer is the very essence of decentralization and avoiding centralized third parties.

What has any of that got to do with trading peer to peer?

So it's a lie then.

You cannot say that 2+2=5 is not a lie but simply missing the phrase "as long as you add one more". If you miss out a piece of information that fundamentally changes the entire concept of what you are saying, then you are lying. What next? We claim that all hot wallets are safe (as long as you never connect to the internet)?

This was a willful lie, and one which Ledger were quite happy to not correct because it made them profit.

Technically no, because as vjudeu has pointed out, no one would join my chain anyway since I would have to hard fork to drop the difficulty like this. I was simply using it as an analogy as to why the longest chain is not synonymous with the chain with the most work.

For the longest/most work argument, it doesn't matter. Even one block more would be enough for all nodes to swap to the longer chain if this was the criteria being used.

If we did use the longest chain, then what would be possible would be a miner mining in secret while manipulating the time stamps on their blocks to artificially drop the difficulty. Theoretically a miner can drop the difficulty to 1 by incrementing the timestamp on the first 2,015 blocks of each difficulty period by 1 second, and then setting the final block's timestamp to the current time. If we actually used longer chain rather than most chain work, then a very small minority miner could reorg as much of the blockchain as they liked by using this method.

Agree with many of the suggestions above. Kycnot.me, Bisq, and AgoraDesk are my go to solutions at the moment.

Absolutely, but I'm also a big fan of cash trades since they leave no paper trail for the government/banks/exchanges to use to spy on you. I've done many cash trades in my life, and I've written before on why I don't think they are high risk and how to keep yourself safe when doing them:


There is also a useful guide from Bisq here: https://bisq.wiki/Face-to-face_(payment_method)

It says nothing about Electrum, since Electrum can be used in a variety of ways, as a hot wallet, or a cold wallet, or a multi-sig wallet, or a 2FA wallet, and so on.

It does mean that your specific wallet is no longer non-custodial since other people have the ability to take all your coins without your consent.