Post your SegWit questions here - open discussion - big week for Bitcoin!

[Thekool1s]

I don't understand the technical side of segwitx2 and UASF, can you guys link me to a quality article, explaining the difference between two? Or can you tell me the differences in layman's terms, is it beneficial? And what is the difference between segwitx2 and segwit? I know that segwit was about taking out the "junk" from transaction, but what is different in segwitx2? Please don't mind these noobish questions, I have been out of touch from the technical side of bitcoin from a long period. Thanks.

[error08]

Have you any idea how easy it is to re-provision the existing BTC infrastructure for BCC?  Let's put it this way, it's probably 100 times easier to migrate to BCC than it is to code up Segwit transaction support in every exchange site, vendor app, etc. And remember that Segwit software utility support is still below 50%...

If the SHTF with Segwit2x vs. Segwit, things can start happening fast again, like they did in late July...

The fact is bitcoin cash doesn't work until today, it just stuck somewhere and barely did not move up in few days.
People won't believe in bitcoin cash as they are believe in bitcoin, simply because it's natures law of be the first digital currency and I consider bitcoin is better than bitcoin cash.

If another hard fork or chain split will happen because of segwit2x, people will chose bitcoin over segwit2x.
Segwit software will go in Live on August 21st, hopefully it could be 100% works.

[hv_]

Have you any idea how easy it is to re-provision the existing BTC infrastructure for BCC?  Let's put it this way, it's probably 100 times easier to migrate to BCC than it is to code up Segwit transaction support in every exchange site, vendor app, etc. And remember that Segwit software utility support is still below 50%...

If the SHTF with Segwit2x vs. Segwit, things can start happening fast again, like they did in late July...

The fact is bitcoin cash doesn't work until today, it just stuck somewhere and barely did not move up in few days.
People won't believe in bitcoin cash as they are believe in bitcoin, simply because it's natures law of be the first digital currency and I consider bitcoin is better than bitcoin cash.

If another hard fork or chain split will happen because of segwit2x, people will chose bitcoin over segwit2x.
Segwit software will go in Live on August 21st, hopefully it could be 100% works.

Yeah. Thats how we humans act. It takes a little while and we get used to, no matter if sth better comes up.
It took about 8 years to get used to Bitcoin. So why use Bitcoin Cash?

I predict same for SW, at least for some 'users' and many miners...

[Qoheleth]

I am not a technical person. So I am still confused about SegWit. I have still no clue what actually it is. The only thing I know that it helped the BTC value rise. Can anyone describe easily what SegWit  actually is?

The very short version of the story is this:

• When people send their coins to someone else, that's a "transaction".
• They "sign" the transaction to prove to the network that they have the right to spend the coins.
• Before SegWit, transactions and signatures were sent out as part of the same document.
• After SegWit, they're sent out separately - like signing the back of a piece of paper instead of the front.

Why does this matter? It turns out it's useful for letting the Bitcoin network process more transactions per second. Right now there's a limit on how many transactions can be processed per second, because everyone has to double-check whether the transactions are 100% correct, and we want to make sure they can keep up.

It turns out, moving the signature out of the transaction itself helps that in two ways:

1) Partial Verification
Part of what makes double-checking transactions a slow process is that they have to be sent to you before you can start to check them. Moving the signatures means that Alice can check the transactions, and then start forwarding them on to Bob right away, even before she's had a chance to check the signatures (she can tell Bob later should the signatures turn out to be bogus). This means less latency in passing along transactions - they travel faster - and so a block can include about half again as many transactions as used to fit inside.

2) "Fixing Malleability"
The way Bitcoin has worked up to now, since the signature is part of the transaction, changing the signature changes the transaction's identity. Even though all the same coins are being spent in the same way, it's a "different" transaction than before. And it turns out anyone can "smudge" a signature slightly, such that it's still valid, but it's "changed" enough to trigger this situation.

This made it harder to write more complicated chains of transactions - where the transactions depend on each other.

One example of these "complicated transactions" is a "payment channel". The idea here is that if Alice and Bob send coins back and forth a lot, they can compress all of their sending back and forth into two transactions - one to "open" the channel, and one to "close" it and settle up. This saves everyone the hassle of double-checking all of Alice and Bob's payments individually; they can just check that the settling-up at the end was valid. (If you've heard the phrase "lightning network", it's basically just a much more advanced version of this same idea.)

With signatures stored inside their transactions, this was really hard to set up correctly, because if the transaction that "opens" the channel gets its signature smudged, the "settling-up" can't find that transaction anymore, so the coins will be left in limbo.

But with SegWit, the signatures aren't inside the transactions. So even if the signatures get smudged, the "settling-up" transaction can still find the "open" transaction, and the technique works.


Together, in theory, (1) and (2) can significantly increase the amount of Bitcoin transactions that can be sent per second. And that means transaction fees go down, and Bitcoin gets cheaper to use. And at the same time, (2) increases the number of interesting things you can do with your bitcoins.

Since both of those make Bitcoin more valuable, the price goes up. ^_^

[anzy]

Since both of those make Bitcoin more valuable, the price goes up. ^_^

Thanks for the perspective, to help make sense of the madness.

[codehtcmail]

I am not a technical person. So I am still confused about SegWit. I have still no clue what actually it is. The only thing I know that it helped the BTC value rise. Can anyone describe easily what SegWit  actually is?

The very short version of the story is this:

• When people send their coins to someone else, that's a "transaction".
• They "sign" the transaction to prove to the network that they have the right to spend the coins.
• Before SegWit, transactions and signatures were sent out as part of the same document.
• After SegWit, they're sent out separately - like signing the back of a piece of paper instead of the front.

Why does this matter? It turns out it's useful for letting the Bitcoin network process more transactions per second. Right now there's a limit on how many transactions can be processed per second, because everyone has to double-check whether the transactions are 100% correct, and we want to make sure they can keep up.

It turns out, moving the signature out of the transaction itself helps that in two ways:

1) Partial Verification
Part of what makes double-checking transactions a slow process is that they have to be sent to you before you can start to check them. Moving the signatures means that Alice can check the transactions, and then start forwarding them on to Bob right away, even before she's had a chance to check the signatures (she can tell Bob later should the signatures turn out to be bogus). This means less latency in passing along transactions - they travel faster - and so a block can include about half again as many transactions as used to fit inside.

2) "Fixing Malleability"
The way Bitcoin has worked up to now, since the signature is part of the transaction, changing the signature changes the transaction's identity. Even though all the same coins are being spent in the same way, it's a "different" transaction than before. And it turns out anyone can "smudge" a signature slightly, such that it's still valid, but it's "changed" enough to trigger this situation.

This made it harder to write more complicated chains of transactions - where the transactions depend on each other.

One example of these "complicated transactions" is a "payment channel". The idea here is that if Alice and Bob send coins back and forth a lot, they can compress all of their sending back and forth into two transactions - one to "open" the channel, and one to "close" it and settle up. This saves everyone the hassle of double-checking all of Alice and Bob's payments individually; they can just check that the settling-up at the end was valid. (If you've heard the phrase "lightning network", it's basically just a much more advanced version of this same idea.)

With signatures stored inside their transactions, this was really hard to set up correctly, because if the transaction that "opens" the channel gets its signature smudged, the "settling-up" can't find that transaction anymore, so the coins will be left in limbo.

But with SegWit, the signatures aren't inside the transactions. So even if the signatures get smudged, the "settling-up" transaction can still find the "open" transaction, and the technique works.


Together, in theory, (1) and (2) can significantly increase the amount of Bitcoin transactions that can be sent per second. And that means transaction fees go down, and Bitcoin gets cheaper to use. And at the same time, (2) increases the number of interesting things you can do with your bitcoins.

Since both of those make Bitcoin more valuable, the price goes up. ^_^

But is Segwit really working now ? I see the transactions are high fees, many transactions stuck without confirmation...

[-ck]

But is Segwit really working now ? I see the transactions are high fees, many transactions stuck without confirmation...

It hasn't been activated yet so no, it's not working, because it can't be.

[Batmanvsduecare]

But is Segwit really working now ? I see the transactions are high fees, many transactions stuck without confirmation...

It hasn't been activated yet so no, it's not working, because it can't be.

May I ask why it can't be activated o working ?

[achow101]

May I ask why it can't be activated o working ?

Segwit can't work until it is activated. Segwit is currently not activated, it is only locked in. This means that it will become active after a certain block height, 481824. It is currently not past that block height.

[JayJuanGee]

May I ask why it can't be activated o working ?

Segwit can't work until it is activated. Segwit is currently not activated, it is only locked in. This means that it will become active after a certain block height, 481824. It is currently not past that block height.

There is about one more week remaining before segwit goes active.  Does anyone anticipate anything dramatic to occur or to witness any dramatic changes? 

I was thinking that spam attacks might go up after segwit goes active to create the impression that segwit is not helping anything, but I could be too pessimistic in my current tentative expectations.

[virasog]

For a lot of people they need to back off on the questions it's just going to confuse them a lot. Suffice it to say that a series of security and helper code Snippets were added to the original code. If you want to go beyond that and of course post your questions, but just understand that you might be confusing yourself more than it's worth.

[BeastLee]

I've been in bitcoin for years andI cannot wait for segwit, it allows for so many things.Some miners could explot a potential vulnerability though, could steal money held in segwit format addresses creating a DAO event, could be abused.

[hv_]

Why is there such a drama about the 2x what was mentioned many year ago, agreed in some tables and seen on roadmaps for long time now?

Why is there people out there risking so much for 'no big deal' thingy?

Is it still the HF fear?

Could we get some 'math' based explanation despite fishy undefined fears?

What is spam
What is enough decentralization
What is security from decentralization
What dynamics we are in and how can we model the future
What is consensus
Why not HF if enough nodes signal upgrade
How is best way to have most on board in future
How is best way getting things done risk free for business with big skin in the game
How get the reputation up for growth

.??

Sure forums looks not the best place but....

[diagla]

So when is Lightning Network and all the SegWit upgrades going to be implemented? Will we see atomic swaps with Litecoin or any other cryptocurrencies?

[HauntingT-Rex]

How long do you guys think it will take before segwit starts having a major effect on the fees?

[JayJuanGee]

How long do you guys think it will take before segwit starts having a major effect on the fees?

You mean to lower fees even more than they already are? 


In recent days I sent about 50 transactions low and high value and I was using between $.10 and $.30 per transaction - and some were quite high transaction amounts...  Some transactions took a bit longer to go through, but they all went through in less than 24 hours.   Really amazing!!!   Sure the higher ones went through in less than an hour, but still.. pretty decent.

As far as getting advantages from segwit activation (for example lighting network) could take several months to see actual advantages, so that will be a curious development to watch, as you mentioned, and surely there are better technical folks that could speculate on these matters.

[Carlton Banks]

How long do you guys think it will take before segwit starts having a major effect on the fees?

As far as getting advantages from segwit activation (for example lighting network) could take several months to see actual advantages, so that will be a curious development to watch, as you mentioned, and surely there are better technical folks that could speculate on these matters.

I think T-Rex means the extra blocksize space

Actual Segwit activation happens at block 481824, according to achow101 above. From there on, people can start using 4MB of blocksize, but only if they're sending to a Segwit address. That will happen before the end of this week, I think around Wednsday or Thursday.

So, you can expect Bitcoin service providing companies (exchanges and larger retailers) to roll out the ability to send to Segwit addresses pretty quick, both to use business2-business and customer-2-business. But regular users need to start using Segwit addresses too, and that takes as long as it takes, no one can force people to do it (the old addresses still work just fine). Miners may begin to incentivise this by prioritising Segwit transactions more, but they already prioritise on the basis of transaction size, so any Segwit incentive would have to be over and above the existing fee per kB logic. All that will take between weeks and months to play out, possibly longer for the last P2PKH addresses to finally move to P2WPKH (the Segwit address/script type).

In addition, there's another BIP out there (171 i think?) that adds a new Segwit specific address format (current practice will be to use Segwit via P2SH addresses). This will be a whole extra new Segwit rollout of sorts. Hopefully, it will be tested and finalised for 0.15.1 (but I'm not at all sure on the specifics, that's just my ideal scenario). This will only add weeks and months to the overall switchover period, but bech32 (the name for the tech behind this new format) has alot of advantages.


Lightning? I expect we can see some test channels running quickly after activation of Segwit, but I think the software clients are still in development even now. Anyone know some more?

[cr1776]

How long do you guys think it will take before segwit starts having a major effect on the fees?

As far as getting advantages from segwit activation (for example lighting network) could take several months to see actual advantages, so that will be a curious development to watch, as you mentioned, and surely there are better technical folks that could speculate on these matters.

I think T-Rex means the extra blocksize space

Actual Segwit activation happens at block 481824, according to achow101 above. From there on, people can start using 4MB of blocksize, but only if they're sending to a Segwit address. That will happen before the end of this week, I think around Wednsday or Thursday.

So, you can expect Bitcoin service providing companies (exchanges and larger retailers) to roll out the ability to send to Segwit addresses pretty quick, both to use business2-business and customer-2-business. But regular users need to start using Segwit addresses too, and that takes as long as it takes, no one can force people to do it (the old addresses still work just fine). Miners may begin to incentivise this by prioritising Segwit transactions more, but they already prioritise on the basis of transaction size, so any Segwit incentive would have to be over and above the existing fee per kB logic. All that will take between weeks and months to play out, possibly longer for the last P2PKH addresses to finally move to P2WPKH (the Segwit address/script type).

In addition, there's another BIP out there (171 i think?) that adds a new Segwit specific address format (current practice will be to use Segwit via P2SH addresses). This will be a whole extra new Segwit rollout of sorts. Hopefully, it will be tested and finalised for 0.15.1 (but I'm not at all sure on the specifics, that's just my ideal scenario). This will only add weeks and months to the overall switchover period, but bech32 (the name for the tech behind this new format) has alot of advantages.


Lightning? I expect we can see some test channels running quickly after activation of Segwit, but I think the software clients are still in development even now. Anyone know some more?

I think BIP173 is what you are thinking of:
https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki

As far as when, that is still up in the air.

[Carlton Banks]

I think BIP173 is what you are thinking of:
https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki

Thanks cr1776, that's it

[conspirosphere.tk]

So I'm reading that this Segwit2X forking could expose BTC users to replay attacks (and maybe to other threats via segwit), but it is not clear at what conditions. To effect replay attacks would take a majority of mining power? Or what exactly?