Homework on Soft and Hard Forks - Questions

Blockchain and Bitcoin 101
#3853
  1. What is the difference between a softfork and a hardfork?

Hard fork means make previously invalid blocks valid
in order to avoid a fork 100% of all nodes need to make an update

Soft fork means make previously valid blocks invalid

>50% of hash power to avoid a fork
<50% of updates  to make a fork

expansion and contraction rules
Hard fork : block <=1mB
Soft fork : block<=0.5mB

  1. What are some of the reasons why you would do a hardfork?
    Make a new currency, change the consensus rules and clear update.

  2. What are some of the risks with performing a hardfork?
    Split hash power - less security in network
    Split the chain
    Split the community

1 Like
#3854
  1. What is the difference between a softfork and a hardfork?

A soft fork is an update that makes previously valid blocks invalid and a hard fork is an update that makes previous invalid blocks valid. On a soft fork as long as you have more than 50% of the hash power the update will lead to no fork, whereas having less than 50% of the hash power this would cause a fork. A hard fork happens when a percentage of the network even if its 1% of the network doesnā€™t update due to a split of opinion for example, this would result in a hard fork. Regardless of how many nodes update during a hard fork the update will cause a chain split which is the difference between a hard and soft fork.

  1. What are some of the reasons why you would do a hardfork?

To replace and old consensus rule with a new one as an example by increasing or decreasing the block size (expansion or contraction of the rule set). Itā€™s a clear update meaning; by not updating youā€™ll be kept on the previous chain once the hard fork update is complete and those who update will be on the new chain. A hardfork its democratic update. You can also create a new currency by harforking.

  1. What are some of the risks with performing a hardfork?

You end up splitting the chain which splits the community. Hash power therefore is split as well which reduces security to the network.

1 Like
#3855

  1. A softfork is an update that makes previously valid blocks invalid and a hardfork is an update that make previously invalid blocks valid. With a softfork you only need less than 50% of hash power.

  2. To have a clear update and demographics.

  3. We split the chain and community. We get a new currency. Hash power is split and we reduce the security.

1 Like
#3856

  1. What is the difference between a soft fork and a hard fork?
    A fork is a code change in the rule set governing block production. A change in the ruleset that creates a soft fork make previously valid blocks invalid, while a change in rules that creates a hard fork allows previously invalid blocks to be valid. Soft forks apply a contraction of block acceptance and hard forks lead to an expansion of block acceptance.

  2. What are some of the reasons why you would do a hard fork?
    A hard fork creates an expansion on the rule-set governing block production. Hard forks are usually done to increase security, increase the efficiency of the blockchain or to reduce costs.

  3. What are some of the risks with performing a hard fork?
    The main risk of a hard fork on any blockchain is a reduced level of security as the hash rate is decreased due to the division of miners. Risk is also created by a division in the network community confidence. The economic risk is the value of the original cryptocurrency may be reduced due to another cryptocurrency created by the hard fork competing with the original in price.

1 Like
#3857

Homework on Soft and Hard Forks - Questions

  1. What is the difference between a softfork and a hardfork?
  • hardfork is making previous invalid blocks valid, and softforks makes previous valid blocks invalid.
  1. What are some of the reasons why you would do a hardfork?
  • To create a new coin. to create a new ruleset.
  1. What are some of the risks with performing a hardfork?
  • Some hashpower would build on the new chain. and the both chains are less secure.
1 Like
#3858
  1. Hardfork update is an expansion of the rule set to make previous invalid blocks valid and softfork update is a contraction of the rule set that makes valid blocks invalid.
  2. You would do a hardfork when a change in consensus rules are needed for the network.
  3. The risks involved with a hardfork is the hash power splits into two chains and is less secure.
1 Like
#3859

1.The difference is that softforks make previously valid blocks invalid (contraction rule change), and hardforks make previously invalid blocks valid (expansion rule change).
2. You might need to do a hardfork in order to correct important security risks found in older versions of the software, or to add new functionality.
3. Risks with performing a hardfork are you could split the chain (unless 100% of the nodes accept the changes), and therefore you could split the community, and split the hash power which will reduce security.

1 Like
#3860

1.A SF is making previously valid blocks invalid and a HF is making previously invalid blocks valid.

2.Some nodes no longer meet consensus
Security risks found in older versions

  1. A blockchain that is less secure and more vulnerable to attacks.
    If a split occurs between the miners who secure the network and the nodes that help validate transactions, the network itself becomes less secure and more vulnerable to attacks.
1 Like
#3861

Softforks are backwards compatible while hardforks are not. Softfork reduces rules for valid blocks while hardfork increases rules for valid blocks.

Hardforks perform a clear upgrade and is more democratic than a softfork. It is done to fix protocol bugs and to improve performance.

The risks associated with hardforks is splitting into 2 coins and a so-called replay attack. Transferring signed txs from one chain to another. Security is also reduced.

1 Like
#3862

  1. What is the difference between a softfork and a hardfork? A softfork contracts the rule set (makes previously valid blocks invalid) whereas a hardfork expands the rule set (makes previously invalid blocks valid).

  2. What are some of the reasons why you would do a hardfork? To change consensus.

  3. What are some of the risks with performing a hardfork? A reduction in security as hashpower is reduced.

1 Like
#3863

  1. What is the difference between a softfork and a hardfork?
    -A softfork is a contraction that reduces the rules for valid blocks while hardforks are an expansion of the rules for valid blocks.

  2. What are some of the reasons why you would do a hardfork?
    -Clear update and they are more democratic.

  3. What are some of the risks with performing a hardfork?
    -Hash power split which lowers security of the network.

1 Like
#3864

  • What is the difference between a softfork and a hardfork?
    A hard fork makes previously invalid blocks valid (an expansion of the rule set), while a soft fork makes previously valid blocks invalid (a contraction of the rule sets)

  • What are some of the reasons why you would do a hardfork?
    If you want to have a change in consensusā€¦perhaps to create a new coin

  • What are some of the risks with performing a hardfork?
    A reduction in hash power for the original chain is a risk, which would then potentially reduce security in the chain. Another risk is splitting the community

1 Like
#3865

  1. A softfork changes previously valid blocks into invalid blocks because of a contraction in the ruleset while a hardfork changes previously invalid blocks into valid blocks because of rule expansion.

  2. If you want to change the consensus rules of the blockchain.

  3. You run the risk of splitting the chain, the community and the hash power, which in turn reduces the security.

1 Like
#3866
  1. What is the difference between a softfork and a hardfork?

Basically:

  • Softfork: update that makes previous valid blocks invalid - expansion
  • Hardfork: update that makes previous invalid blocks valid - contraction
  • A softfork causes a change that is compatible with the previous state of the chain
  • A hardfork is not compatible with the previous state of the chain so you will be on another chain (other rules) if you do not apply the change.
  1. What are some of the reasons why you would do a hardfork?
  • A hardfork can expand the rules of the network.
  • The changes that come with a hardfork make any following transactions incompatible with the network rules that were in place before the update.
  • These new transactions function on a separate chain, so participants can use a hardfork to pursue their own version of truth on their own separated blockchain.
  • In other words, you can create a new coin by hardforking. Performing a hardfork can also take away hash power away from the original chain (reducing security)
  1. What are some of the risks with performing a hardfork?
  • You risk a loss of hash power from the original chain which reduces security.
  • It can split the community and lead to a lot of infighting.
  • There could be unforeseen vulnerabilities on a new chain with significantly less hash power than the original chain.
  • decreased security with a chain split because you have less hash power if itā€™s split between two chains
1 Like
#3867

  1. Hardforks make previously valid blocks, invalid. Softforks make previous invalid blocks, valid

  2. It would be a clear update.

  3. split the chain, split the community, less security

1 Like
#3868

A Fork is an update given to a specific chain. This are divided into two categories ā€œHardforkā€ and ā€œSoftforkā€. What a ā€œHardforkā€ do is modify and expand a set of rules and previous Invalid Blocks are now valid, contrary to the ā€œSoftforkā€ that valid blocks are now invalid and the rules are shrink. A ā€œHardforkā€ will be useful when changing the Consensus Rules. Performing a ā€œHardforkā€ may leave to the Hash power of the Chain to reduce therefore reducing the security also may lead to the fragmentation of the community.

1 Like
#3869

1. What is the difference between a softfork and a hardfork?

A softfork is a fork that results from a rule change in the btc network that makes previously valid blocks invalid.

A hardfork is a fork of the blockchain that results from a rule change in the btc network that makes previously invalid blocks valid.

2. What are some of the reasons why you would do a hardfork?

A hardfork is a more democratic process whereby a majority of the nodes will choose to start mining on the forked chain instead of the original chain. Therefore, a hardfork would be desired if a majority of the network wants an update to occur.

3. What are some of the risks with performing a hardfork?

When a hardfork occurs, an inevitability is that hash power is reduced. Some miners will start to mine on the forked chain hence reducing hash power and reducing network security.

I think the reason why reduced hash power decreases network security is due to the fact that less blocks are now being added per unit time and it opens the door to a potential bas actor to change the transactions in a block and quickly re-mine all the hashed links including those of the newly added blocks because they are being added slowly from before.

The paragraph directly above I am unsure about, hence the reason why I started it with ā€œI thinkā€ so if someone can confirm it that would be great! Thank you!

1 Like
#3870

  1. A hard fork update allows for a more permissive ruleset, whereas a soft fork update implements a more restrictive one (each come with their own effects on the blockchain, depending on community uptake)

  2. a hard fork is beneficial when you want to allow the community members to make their own decision with respect to whether or not they will keep their old ways or actually go ahead with an updateā€¦ i imagine there are permissivity reasons one might want to use a hard fork, e.g. the current ruleset is just too restrictive and you need something to change in the protocol for security or other purposesā€¦

  3. the drawbacks of performing a hard fork are primarily the weakened hash power that results from allowing the community to split itself (in practice this is likely not a problem if much more than a majority join update to the new fork), but also there may be some morale issue that results from hardcore philosophical disagreement with others in the current community about why or why not to updateā€¦ dilution in more ways than one.

#3871

i think the security issue is a result of fewer nodes needing to be overtaken in order to falsify a transaction (i donā€™t think blocks per time are adversely affected since thatā€™s a result of the target difficulty, at least in btc protocol), i.e. less work proven means less work needed to ā€œre-proveā€ a false chainā€¦ in practice thought i imagine thatā€™s so difficult that i might be focusing on the wrong aspect of how hash power yields seuirity ā€¦

#3872

You are right, if fewer blocks are being added per unit time, the blockchain might be exposed to 51% attack.