How do the signatures work? They are separated into two separate blocks so there would be two blockchains running? One would store a block of transactions and a block of signatures?
blockstream put in the FIBRE network to change the topology of the network (as gatekeepers) so that if segwit activates the segwit nodes control what gets filtered down to old native nodes.
in simple terms segwit nodes receive a cluster of data which is one lump of data called the blockweight where the signatures have their own txid to link back to the txid of the baseblock. if they have whitelisted old native nodes they have to send the smaller 'base' block' to old native nodes
its bait and switched to pretend its one network but because the old nodes are not receiving the same data as the segwit nodes. a fresh segwit node wont sync from a native node.
a native node wont receive segwit unconfirmed transactions. so its a 'pretend' single network. but with differing data held and/or relayed.
same goes with segwits pruned nodes. a segwit node wanting a full sync wont sync from a pruned node. so again all these core features are causing issues for the REAL full node count.because not all the nodes hold all the same data.
core have swept under the carpet how they have made anything not segwit as being second class. but pretended its all good because its "compatible"
as you can see below.
on the left is what people for 6-7 years thought the node network looked like. with pools sending out data and EVERYONE sharing the same data.
on the right is how how segwit/fibre has changed the network topology. to centralise segwit as the gate keepers of what data non segwit nodes get
and yes, segwit nodes could simply not whitelist old native nodes and make it reliant on the pools to send data to old nodes, which looking at this image below is the one on the right.(very worse case scenario, but plausible)
EDIT:gmaxwell buzzwords
downstream(old) <-> upstream(segwit) <-> pool
upstream(segwit) <-> pool<-> downstream(old)
its all explained here including the bit about signature/tx data
https://bitcointalksearch.org/topic/m.17607565
Latest on Dangers posed by Segwit,
Words of a Former Segwit Supporter Who has Realized the Truth!
https://www.reddit.com/r/btc/comments/5vbofp/initially_i_liked_segwit_but_then_i_learned/
FYI:
Segwit => Trojan Virus for a Blockchain
Words of a Former Segwit Supporter Who has Realized the Truth!
Quote
Initially, I liked SegWit. But then I learned SegWit-as-a-SOFT-fork is dangerous (making transactions "anyone-can-spend"??) & centrally planned (1.7MB blocksize??). Instead, Bitcoin Unlimited is simple & safe, with MARKET-BASED BLOCKSIZE. This is why more & more people have decided to REJECT SEGWIT
https://www.reddit.com/r/btc/comments/5vbofp/initially_i_liked_segwit_but_then_i_learned/
Quote
You wanted people like me to support you and install your code, Core / Blockstream?
Then you shouldn't have a released messy, dangerous, centrally planned hack like SegWit-as-a-soft-fork - with its random, arbitrary, centrally planned,
ridiculously tiny 1.7MB blocksize - and its dangerous "anyone-can-spend" soft-fork semantics.
Now it's too late. The market will reject SegWit - and it's all Core / Blockstream's fault.
The market prefers simpler, safer, future-proof, market-based solutions such as Bitcoin Unlimited.
Then you shouldn't have a released messy, dangerous, centrally planned hack like SegWit-as-a-soft-fork - with its random, arbitrary, centrally planned,
ridiculously tiny 1.7MB blocksize - and its dangerous "anyone-can-spend" soft-fork semantics.
Now it's too late. The market will reject SegWit - and it's all Core / Blockstream's fault.
The market prefers simpler, safer, future-proof, market-based solutions such as Bitcoin Unlimited.
Quote
The damage which would be caused by SegWit (at the financial, software, and governance level) would be massive:
Millions of lines of other Bitcoin code would have to be rewritten (in wallets, on exchanges, at businesses) in order to become compatible with all the messy non-standard kludges and workarounds which Blockstream was forced into adding to the code (the famous "technical debt") in order to get SegWit to work as a soft fork.
SegWit was originally sold to us as a "code clean-up". Heck, even I intially fell for it when I saw an early presentation by Pieter Wuille on YouTube from one of Blockstream's many, censored Bitcoin scaling stalling conferences)
But as we all later all discovered, SegWit is just a messy hack.
Probably the most dangerous aspect of SegWit is that it changes all transactions into "ANYONE-CAN-SPEND" without SegWit - all because of the messy workarounds necessary to do SegWit as a soft-fork. The kludges and workarounds involving SegWit's "ANYONE-CAN-SPEND" semantics would only work as long as SegWit is still installed.
This means that it would be impossible to roll-back SegWit - because all SegWit transactions that get recorded on the blockchain would now be interpreted as "ANYONE-CAN-SPEND" - so, SegWit's dangerous and messy "kludges and workarounds and hacks" would have to be made permanent - otherwise, anyone could spend those "ANYONE-CAN-SPEND" SegWit coins!
Segwit cannot be rolled back because to non-upgraded clients, ANYONE can spend Segwit txn outputs. If Segwit is rolled back, all funds locked in Segwit outputs can be taken by anyone. As more funds gets locked up in segwit outputs, incentive for miners to collude to claim them grows.
Millions of lines of other Bitcoin code would have to be rewritten (in wallets, on exchanges, at businesses) in order to become compatible with all the messy non-standard kludges and workarounds which Blockstream was forced into adding to the code (the famous "technical debt") in order to get SegWit to work as a soft fork.
SegWit was originally sold to us as a "code clean-up". Heck, even I intially fell for it when I saw an early presentation by Pieter Wuille on YouTube from one of Blockstream's many, censored Bitcoin scaling stalling conferences)
But as we all later all discovered, SegWit is just a messy hack.
Probably the most dangerous aspect of SegWit is that it changes all transactions into "ANYONE-CAN-SPEND" without SegWit - all because of the messy workarounds necessary to do SegWit as a soft-fork. The kludges and workarounds involving SegWit's "ANYONE-CAN-SPEND" semantics would only work as long as SegWit is still installed.
This means that it would be impossible to roll-back SegWit - because all SegWit transactions that get recorded on the blockchain would now be interpreted as "ANYONE-CAN-SPEND" - so, SegWit's dangerous and messy "kludges and workarounds and hacks" would have to be made permanent - otherwise, anyone could spend those "ANYONE-CAN-SPEND" SegWit coins!
Segwit cannot be rolled back because to non-upgraded clients, ANYONE can spend Segwit txn outputs. If Segwit is rolled back, all funds locked in Segwit outputs can be taken by anyone. As more funds gets locked up in segwit outputs, incentive for miners to collude to claim them grows.
FYI:
Segwit => Trojan Virus for a Blockchain
