just wondering what is the plan when it comes to roll backs? personally i would go for the "make them impossible to ever do" solution but im interested to hear why they should be allowed and what the devs thoughts are on the matter aswell as how the devs plan to handle roll backs?
also when it comes to 51% attacks… is there anything about nem that means you would need more than 51% of importance to perform a 51% attack? is there any clause in the source to prevent anyone from ever achieving >50% of all importance?
AFAIK rollbacks are possible in NEM just like in any other crypto. I don't every want to see this happening but when shit hit's the fan like it did for NXT then I'd rather have the possiblity to think about than be only able to watch.
About 51% attacks…I'll let a core dev handle that 
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
Hello
I find this problem kid of disturbing because NEM has not escaped totally from centralization.
What I mean by that is that NEM could have same problems with exchanges like the
POW coins like BTC currently have with the mining pools.
Currenty i don't seen any solution to this problem except wider distribution of NEM and building
services around it but I'm afraid that in log run we will see again concentration of NEM (power over the network) into few accounts 
What else could we do to avoid such scenario? :-X
[...] but I'm afraid that in log run we will see again concentration of NEM (power over the network) into few accounts :(
Why?
It is doubtful that any single entity could gain > 25% of the importance if NEM has lots of users.
[...] but I'm afraid that in log run we will see again concentration of NEM (power over the network) into few accounts :(
Why?
Because i see that people tend to copy the same patterns from the "real world" (FIAT based economy system) into "new world" (Crypto based economy system) therefore I expect that like in the current system there could be big cartels forming (joining,overtaking,merging) like it is now until it becomes a monopoly and the only thing that could avoid this is a big user base from the beginning unless
another technical solution could be implemented in NEM itself to prevent such thing even with smaller user base.
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
I dislike that the webstart could be used to perform a manual rollback. Could their be some way of asking users during the webstart process(assuming something like bter hack happens and a roll back is suggested) which block chain they wish could to go with? This sort of centralised power is something we should avoid.
I do trust the devs but it's not me that needs convincing. The devs shouldn't have the power to do a roll back using an automated updater… There needs to be some sort of limitations put in place I think.
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
I dislike that the webstart could be used to perform a manual rollback. Could their be some way of asking users during the webstart process(assuming something like bter hack happens and a roll back is suggested) which block chain they wish could to go with? This sort of centralised power is something we should avoid.
I do trust the devs but it's not me that needs convincing. The devs shouldn't have the power to do a roll back using an automated updater.. There needs to be some sort of limitations put in place I think.
How other cryptos with auto-updating clients handle that ?
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
I dislike that the webstart could be used to perform a manual rollback. Could their be some way of asking users during the webstart process(assuming something like bter hack happens and a roll back is suggested) which block chain they wish could to go with? This sort of centralised power is something we should avoid.
I do trust the devs but it's not me that needs convincing. The devs shouldn't have the power to do a roll back using an automated updater.. There needs to be some sort of limitations put in place I think.
How other cryptos with auto-updating clients handle that ?
I don't know of any that have auto update and I think this could be the reason.
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
I dislike that the webstart could be used to perform a manual rollback. Could their be some way of asking users during the webstart process(assuming something like bter hack happens and a roll back is suggested) which block chain they wish could to go with? This sort of centralised power is something we should avoid.
I do trust the devs but it's not me that needs convincing. The devs shouldn't have the power to do a roll back using an automated updater.. There needs to be some sort of limitations put in place I think.
How other cryptos with auto-updating clients handle that ?
I don't know of any that have auto update and I think this could be the reason.
I thought nxt was auto-updating? I mean it never worked for me but it did prompt me to download a new version and the download started (but it always resulted in an error).
I don't see it as a big problem. Most 24/7 harvesters will run standalone and that doesn't auto-update.
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
I dislike that the webstart could be used to perform a manual rollback. Could their be some way of asking users during the webstart process(assuming something like bter hack happens and a roll back is suggested) which block chain they wish could to go with? This sort of centralised power is something we should avoid.
I do trust the devs but it's not me that needs convincing. The devs shouldn't have the power to do a roll back using an automated updater… There needs to be some sort of limitations put in place I think.
How other cryptos with auto-updating clients handle that ?
I don't know of any that have auto update and I think this could be the reason.
I thought nxt was auto-updating? I mean it never worked for me but it did prompt me to download a new version and the download started (but it always resulted in an error).
The official dev release is not autoupdating I know that much. The simple version could but I don't think it is tbh. The webstart works for me it updated my client from 0.4.12 to 0.4.17 no problem. The devs having this power is not going to even remotely good or nems public image… I can see all the benefits and it's brilliant and all but I can see fudsters using it as pretty powerful ammo…
There are natural rollbacks in every crypto currency. This happens each time when you are on a fork and NIS resolves the fork. Those rollbacks are performed automatically but can only happen up to a certain depths. In the current version the maximum depth for resolving a fork is 360 blocks. If you are stuck on a fork deeper than this you will be stuck forever (means you have to delete the db and resync from scratch).
Manual rollbacks are of course possible if the developers release a new version which hard forks the blockchain. But it is up to the users if they want to use the new version or not (webstart kind of undermines this concept as it automatically upgrades the software at start). I personally think that if something catastrophically happens which kills NEM we should really consider a rollback. But it should be up to the community to decide.
If you gain more than 50% importance you have won and control NEM. But that is true for all other crypto currencies as well. In fact, even if you gain 40% importance, the chance that you can create a fork which is deeper than the above mentioned maximum depth for automatic resolving forks is quite high. So I think a single entity should not have more than 25% importance because this leads to big problems (the trust in the currency will fall).
There is no check for an account having more than x% importance. This would be useless because an attacker can always spread his importance among many accounts.
Bloody Rookie
I dislike that the webstart could be used to perform a manual rollback. Could their be some way of asking users during the webstart process(assuming something like bter hack happens and a roll back is suggested) which block chain they wish could to go with? This sort of centralised power is something we should avoid.
I do trust the devs but it's not me that needs convincing. The devs shouldn't have the power to do a roll back using an automated updater.. There needs to be some sort of limitations put in place I think.
How other cryptos with auto-updating clients handle that ?
I don't know of any that have auto update and I think this could be the reason.
I thought nxt was auto-updating? I mean it never worked for me but it did prompt me to download a new version and the download started (but it always resulted in an error).
The official dev release is not autoupdating I know that much. The simple version could but I don't think it is tbh. The webstart works for me it updated my client from 0.4.12 to 0.4.17 no problem. The devs having this power is not going to even remotely good or nems public image.. I can see all the benefits and it's brilliant and all but I can see fudsters using it as pretty powerful ammo..
I'm pretty sure i was using the official client...nevermind that now.
The devs have power no matter what. This is just a more obvious way in which that power manifests. This is true for every crypto.
guys, please cut the post sometimes, you don't have to quote everything 
NXT autoupdate works quite fine. There were just few updates where it asked me to download new version manually (it said automatic update is impossible).
@kody: re:automatic update, keep in mind that is only true for webstart users, and I believe most of our network will depend on standalone users, who must update manually. Not to mention, that we wouldn't do anything like fork resolve without community agreement.