Today's topic is about
the consensus algorithm - Delegate Proof of Capacity (DPoC) which we developed for
FiiiCoin.
History
Proof of Capacity
(PoC) or also known as Proof of Space (PoSpace) is a consensus algorithm originated
from Burstcoin which is somehow similar to Proof of Work (PoW) that you
can find in Bitcoin. However, PoC uses storage instead
of computing power to perform proof of work. Burstcoin is the first
cryptocurrency that uses PoC consensus in year 2014.
Why PoC?
We like the idea of
Burstcoin which is energy efficient for mining and the concept is just nice to
fit into our FiiiPOS terminal to enable for mining. We all know that the
hardware spec of a POS terminal is similar to a mobile phone. Mining a PoW
crypto which is power hunger using mobile phones are unfeasible, considering
the weak CPU, the heat generation and the battery lifespan will be shorten
quicker than usual, also trying to compete with ASIC using mobile phones is a crazy
idea.
How PoC Work?
PoC is a consensus
where miners make use of their device storage to keep the pre-computed hashes
prior to the mining process begun. Every miner need to allocate a desired
amount of storage for mining, then the mining script will plot the hashes to
the allocated space and also group the hashes into scoop.
Image credits to Burstcoin
Whitepaper
Once the hashes have
been plotted into the allocated space. miner connects to the Node to get mining
work which contain the block producer signature, base target and next block height.
The miner then determines which
scoop to look for the hashes, then start scanning
the hashes in the plot file to look for the correct nonce. At this time, there
is no CPU involvement at all. The plot file reading speed and the number of
hashes in the allocated storage space determine the mining success rate.
Every account generates a unique different set of hashes
base on unique account ID and nonce value. And, the miner just need to
pre-compute the hashes once and save into the storage, then these hashes can be
reused multiple time even though there is a block being successfully mined.
The PoC concept is a bit different compare to the Bitcoin
PoW consensus whereby the hash is generated base on the entire block data. However,
in order to mine a PoC block, it is determined by finding the correct nonce
within the target deadline. The Node check the last 30 blocks generation time
to determine the next block target deadline in order to maintain average 5
minutes (24 blocks 4 minutes for Burstcoin) block produce time. The miner need to find
the correct hash within the target deadline.
Why Not Cloud Mining?
The common question
that asked by the people who have listened to our idea: Since mobile phone is
unfeasible for mining, why not put it into cloud or server?
A blockchain are
supposed to be meant for mining for everyone. The original intension of Satoshi
Nakamoto, the founder of Bitcoin, created Bitcoin – a P2P payment system that
govern and maintain by everyone, using the extra computing resource that you
leave it idle. Our objective is to do the same, let everyone participates in
mining, together maintain the blockchain network, while leaving your FiiiPOS
terminal or mobile phone running idle and charging battery.
We do not need
expensive ASIC machine to power the blockchain, wasting too much energy for
little purpose. We emphasize reusability, your mobile phone is the FiiiCoin node,
the more mobile phone from different individual come in as part of the FiiiCoin
blockchain, the higher the security of our FiiiCoin.
FiiiCoin is specifically
designed for ASIC proof, quantum computer proof, cloud mining proof, computer
proof and also restricted to only FiiiPOS and mobile phones allow to participate
in mining. Hence, the consensus – Delegate Proof of Capacity (DPoC) is formed.
PoW vs DPoC
Rule
|
PoW
|
DPoC
|
Finding hash
|
Real time
|
Periodic
|
Hash base
|
Entire Block
|
Device ID + Account ID + Nonce
|
Competition
|
First + Highest Difficulty
|
First + Lowest Target Deadline
|
Compute Power
|
CPU / GPU
|
CPU + Storage
|
Minable
|
Everyone
|
Restricted device only
|
Potential Exploit
Burstcoin being
susceptible to time-memory trade-offs, thus allowing miners to mine using PoW
and using just a small fraction of space to be at the same rate as “honest
miners”. The Burst PoC2 should solve
the problem and FiiiCoin is also prepared for the same potential exploit.
Secondly, in order to
restrict certain device to be able to participate in mining is also a challenge
since today’s virtual machine technology is mature, a PC can easily virtualize
a few mobile phones to perform FiiiCoin mining.
The Balance of Security, Speed, Decentralization
Every blockchain technology always grasp between the balance of
decentralization, security and performance. There is no one silver bullet or
one size fit all solution that can achieve these 3 characteristics. When you
want to improve the security of the blockchain, you either need to jeopardize the
performance or decentralization.
FiiiCoin has been designed specifically for payment
ecosystem, it is a less decentralized blockchain but with better security and
performance. The FiiiPOS and mobile phone mining restriction is to protect our merchants
and supporters interest. With delegated PoC consensus, we can achieve higher transaction
per second by letting the Super Node keep generating block with no restriction, however, it is to be
confirmed later when our technical team finish the development and testing in the test net.
The Super Node responsible in producing blocks,
while the normal node (wallet) is responsible in validating the block and
distribute the data across the blockchain network. All the miners who wish to connect
to the Super Node, they have to either own a FiiiPOS terminal or paying monthly
subscription fee to enable mining with a separate mining software.
Due to the concern of a mobile phone storage
limitation, it is not encouraged to install full node into the mobile phone as
the blockchain size is growing overtime. However, we provide a separate lightweight
wallet that only sync block headers for mobile phone.
The Death
of POS Terminal
POS Terminal manufacturers are facing very
tough competition in the market. There are so many POS terminal that accept
credit card payment or mobile payment choices available. Payment solution
provider or banks are giving out POS terminal to their merchants for free.
There is transaction fee competition as well. It is just a tool for the
merchant to accept payment.
Today, in order to compete with the existing market,
our POS terminal – FiiiPOS need to be capable of generating revenue for our
merchants even there is no transaction at all, especially in the crypto
industry where not many users adopt into it yet and also without government
support. Furthermore, we are into transaction fee war as well, giving lower fee
compare to the bank and other payment provider. The FiiiPOS machine cost can be ROI after a period of time.
With FiiiCoin DPoC design, merchant generate free
FiiiCoin out from their idling and charging POS terminal. The FiiiCoin earning
can be used to offset the transaction fee as well as the cost of the machine. The
FiiiCoin value is maintained by everyone who uses FiiiCoin to make payment. We
are forming an ecosystem that everyone does not dump FiiiCoin to exchange for
fiat currency, instead making it usable anywhere around the world with large
merchant network who own FiiiPOS terminal. This is something that the existing payment
solution provider cannot provide at the moment.
Summary
I believe crypto enthusiast will condemn about
our blockchain design for not being fully decentralized. I would like to
emphasize our priority now is taking care of our merchants and attempting to
build a large payment ecosystem. It is not easy to make everyone happy unless I
sell ice-cream. There is no one size fit all solution. Our goal is to distribute FiiiPOS worldwide and making it available to everyone every where, travelers able to spend crypto overseas without the need to exchange foreign currency.
I believe a crypto which is usable and
acceptable by people is only considered as successful. Cryptocurrency is
not supposed to be a speculative investment tool. It should not be just a
technology showcase as well. No matter how good is your blockchain
technology, when there is no adoption, no application, it is considered meaningless
and valueless.
I am open for any comment, feel free to drop
me a message in the comment section below if you have a better idea in designing
a blockchain for our business model.
