|
|
|
@ -1,15 +1,15 @@ |
|
|
|
# Mastering Komodo Delayed Proof-of-Work |
|
|
|
# Mastering Delayed Proof-of-Work |
|
|
|
|
|
|
|
## by Duke Leto |
|
|
|
|
|
|
|
This is a short technical document aimed at developers who are interested to learn |
|
|
|
more about DPoW and/or want to add it to their a cryptocoin to protect |
|
|
|
against consensus (51%) attacks. These attacks are becoming very common |
|
|
|
against consensus (51%) attacks and double spend attacks. These attacks are becoming very common |
|
|
|
against coins from large to small. |
|
|
|
|
|
|
|
This book assumes basic knowledge of the Bitcoin protocol, Bitcoin source code, |
|
|
|
C++ and basic compiler knowledge. No prior knowledge of Komodo is assumed, this |
|
|
|
work contains a basic introduction of Komodo features. |
|
|
|
C++ and basic compiler knowledge. No prior knowledge of Hush is assumed, this |
|
|
|
work contains a basic introduction of Hush features. |
|
|
|
|
|
|
|
# High Level Overview of KMD DPoW |
|
|
|
|
|
|
|
@ -24,7 +24,7 @@ blockchain. Anybody can use it and implement the service. |
|
|
|
|
|
|
|
## Global Notary Node Network |
|
|
|
|
|
|
|
In more detail, there exist a network of 64 notary nodes spread around the |
|
|
|
For example, say there exist a network of 64 notary nodes spread around the |
|
|
|
globe. They are not in any one physical location, which makes the system |
|
|
|
resilient against a datacenter outage or natural disaster in one geographical |
|
|
|
location. The algorithm NNs use require 13 notary nodes to come together and |
|
|
|
@ -72,29 +72,6 @@ nodes and some exchanges attempt to charge for full node updates (which the |
|
|
|
author finds scammy), so timing the integration of DPoW services can be very |
|
|
|
strategic. |
|
|
|
|
|
|
|
# Double Spend Attack Prevention |
|
|
|
|
|
|
|
It is the authors recommendation that exchanges pause any transactions for |
|
|
|
which data has not yet been notarized to the appropriate chain. For a game |
|
|
|
allowing in-game purchases with digital currencies, it might allow transactions |
|
|
|
up to $10 if the data has been notarized to Komodo, or no limit on transactions |
|
|
|
that have been notarized to Bitcoin. This allows small-value transactions to |
|
|
|
proceed very quickly (Komodo has a 1 minute blocktime) while ensuring |
|
|
|
protection against double-spend attacks for large value transactions. This |
|
|
|
protection comes at the cost of waiting longer, as Bitcoin has 10 minute |
|
|
|
blocktime. |
|
|
|
|
|
|
|
It is important to understand that one half of the process is notarization |
|
|
|
data, which must go from COIN -> KMD -> BTC, and the other half of Double Spend |
|
|
|
Protection is actually looking at this notarization data and deciding if it's |
|
|
|
safe to proceed with some action. Komodo is working on an API to see if a txid |
|
|
|
of a certain dpow-enabled coin has been notarized to KMD and BTC, so that |
|
|
|
exchanges and other parties wanting to protect against double spends can make |
|
|
|
informed decisions, in much shorter time periods than waiting until 120 confirmations. |
|
|
|
|
|
|
|
The API for when notarizations have made it to the KMD chain is at |
|
|
|
https://komodostats.com/api/notary/summary.json . |
|
|
|
|
|
|
|
# DPOWconfs protect against double spends with no code changes |
|
|
|
|
|
|
|
A recent innovation called "DPoW confs" allows |
|
|
|
|
GitHub