PIVX White Paper – Version 1.01, September 2018

Version 1.01, September 2018.
Written and compiled by Strontium

Contributors
presstab, warrows, Rhubarbarian, Sieres, CryptoHB, s3v3nh4cks, random.zebra

Input/Support
Eric_Stanek, Fuzzbawls, SnappySnap, Cryptosi, gets, thuggins, John M, Buer, Evan, deejayem, Rock-N-Troll, Mary, turtleflax,
furszy and Rhubarbarian

 Abstract

Currently, the cryptocurrency market is awash with tokens from parties of varying intent, motivation, and affiliation. The myriad of tokens and projects—some novel and ambitious uses of blockchain, others in essence clones with catchy names—serves as a deterrent to widespread adoption of crypto as a legitimate, borderless alternative to fiat currency. This document serves as a comprehensive resource on the Private Instant Verified Transaction (PIVX) cryptocurrency, a currency whose defining purpose is to provide users with a fast, secure, private, and stable means of transacting over the web. PIVX integrates features inspired by Bitcoin’s pioneering distributed ledger consensus technology; speed and governance accessions from Dash, such as SwiftX (from InstantSend) and a Masternode network; and incentivises Zerocoin protocol anonymity through zPoS. PIVX also incorporates its own features, such as a Proof of Stake consensus algorithm, and a dynamic coin supply restrained by the burning of transaction fees.

Note that this paper, while an extensive introduction and explanation of PIVX, does not contain mathematical or cryptographical breakdowns or explanations. These can be found separately on the PIVX project’s GitHub. 

Table of contents

1 Introduction 1
1.1 Private Instant Verified Transaction 2
1.2 Vision/Manifesto 3
2 Anatomic overview of PIVX 4
2.1 PIVX coin specs 5
2.2 PIVX economics 7
2.2 i Dynamic coin supply 8
2.2 ii Inflation/Deflation 10
2.3 Bitcoin/Litecoin roots 11
2.3 i Scrypt and X11 mining algorithms 13
2.4 Dash roots 14
2.4 i PrivateSend 14
2.4 ii InstantSend 15
2.5 libZerocoin 16
2.6 PIVX innovations 18
2.7 Development and release practices 20

3 Proof of Stake consensus 21
3.1 PIVX Proof of Stake – identity and security 23
3.1 i Addressing Nothing-at-stake criticism 24
3.2 Staking PIVX/zPIV 24

4 Masternode network 25
4.1 Masternode network technical functions 25
4.1 i SwiftX 26
4.1 ii Coin mixing 28
4.2 Masternode decentralised governance 30
4.2 i Proposal voting 31
4.3 Masternode acquisition 33

5 Masternode – staking reward system 35
5.1 Reward balance: staking -masternode 35
5.2 Reward variance: PIV – zPIV 37

6 zPoS – private PoS though the Zerocoin protocol 38
6.1 Zerocoin protocol anonymity 40
6.1 i Zerocoin Bulletproof and setup trust 43
6.1 ii Zerocoin, privacy, and security 45
6.2 zPIV 46
6.3 Minting and staking zPIV for zPoS 48
6.4 zDEX zPIV decentralised exchange 50

1 Introduction

The advent of the blockchain era occurred in 2009 with its implementation in Bitcoin by the entity known as Satoshi Nakamoto. Following Bitcoin’s success, many competing cryptocurrencies—known as altcoins—have arisen. The potential of blockchain to revolutionise not only the way transactions are made, but the way business is conducted across many strata, has seen an explosion of interest in the technology. Currently, the cryptocurrency market is awash with tokens from parties of varying intent, motivation, and affiliation. The myriad of tokens and projects—some novel and ambitious uses of blockchain, others in essence clones with catchy names—serves as a deterrent to widespread adoption of crypto as a legitimate, borderless alternative to fiat currency.

Bitcoin, despite its constant innovation, has so far failed to be widely accepted and adopted as a currency, and remains widely viewed as a store of value rather than means of conducting everyday business. As the world approaches a decade since the launch of Bitcoin, a definitive identity for cryptocurrencies has yet to emerge. This lack of identity has caused the public to view the crypto marketplace as a stock market 2.0. Its volatility and saturation intimidate potential adopters, who regard it not as an alternative to fiat currencies, but as a risky investment opportunity.

In keeping with the spirit of cryptocurrency’s defining goal, PIVX aims to bridge the gap between the tech-savvy and tech-wary. It strives to provide a safe means through which not only investors, but the general public can conduct business without the need for financial institutions or middle-men. PIVX’s aim is to provide the people of the ever more interconnected world with an expedient, private means to conduct business on their own behalf.

1.1 Private Instant Verified Transaction

The Private Instant Verified Transaction (PIVX) cryptocurrency (formerly DNET), is a currency whose defining purpose is to provide users with a truly private means of expediently, securely, and stably transacting over the web. PIVX integrates features inspired by Bitcoin’s pioneering distributed ledger consensus technology; speed and governance accessions from Dash, such as InstantSend and the Masternode network; and features the addition of the anonymity protocol Zerocoin on transactions and staking—all of these heavily customised. PIVX also incorporates its own features, such as a Proof of Stake consensus algorithm, the ability to stake both PIV and zPIV, and a dynamically calibrated coin-supply restrained by the burning of transaction fees.
For more on zPIV see section 6.2.

PIVX is DECENTRALISED, INCENTIVISED, and OPEN-SOURCE. 60-thousand PIV were premined on the genesis block for the purpose of setting up 6 initial Masternodes. This premine was burnt on block 279917. There was no instamine, and no amount of PIV is locked away in order to manipulate the PIVX economy.

As a Proof of Stake cryptocurrency, PIVX is significantly better for the environment than Proof of Work focused cryptocurrencies due to its lower energy consumption requirements.

Zerocoin Proof of Stake (zPoS) allows for PoS rewards to be earned while maintaining and incentivising anonymity.
For more on zPoS see section 6.

PIVX transaction and zPIV minting fees are burnt, and new coins enter at a predetermined rate, thus managing the coin supply and protecting against hyperinflation.

Approximately 16.66% of block rewards are used as treasury to fund the further advancement. The PIVX blockchain pays out this funding via superblocks monthly, through which the self-governed community budget out software development, as well as marketing, translation, QA, etc. via voting.
For more on fee burning see section 2.2.
For more on budget and self-governance see section 4.2.

1.2 Vision/Manifesto

PRIVACY is non-negotiable; it’s a basic human right.

FREEDOM is everything.

TECHNOLOGY is advancing, GOVERNANCE must also.

Privacy ALLOWS the freedom to share what you wish with EVERYONE, but also the freedom to RESTRICT who sees your information.

We believe this is each person’s CHOICE. GOVERNANCE is used to further objectives and FUND development.

The DAOs are untouchable.

Join us WHEN you like, WHY you like, and, for AS LONG as you like.

Let’s explore ALL the options TOGETHER. You are IMPORTANT to US.
It’s TIME we harnessed your FULL potential.

2 Anatomic overview of PIVX

As PIVX exists with the purpose of becoming the quintessential privacy-based currency, its base features are an aggregate of those pre-existing in other currencies. These have been tailored and added to in order to provide a single currency able to perform with the strengths of these currencies without their weaknesses. Beyond this, PIVX, and the untraceable zPIV and Zerocoin protocol, possess further features that set PIVX apart from its predecessors and contemporaries.

The software technology behind PIVX is drawn from a lineage of successful cryptocurrencies, with each having sought to improve upon those before it. PIVX, which started as a code fork of Dash, can draw its root back from there to Litecoin—from which Dash was forked—and back to Bitcoin (it’s worth noting that Dash returned in large to Bitcoin codebase before the PIVX fork). All three of these coins have spent time in the top 10 cryptocurrencies.

pastedGraphic_2.png

A demonstration of the flow of tech from Bitcoin forking to Litecoin; Litecoin forking to Dash, implementing CoinJoin; Dash forking to PIVX, implementing Zerocoin.

PIVX is constantly working to improve upon not only these previous technologies, but upon its own. As such, features once implemented by PIVX, such as the early PoW phase, CoinJoin, and the retired Seesaw mechanism make way for more ambitious features.

 2.1 PIVX coin specs

PoW Phase Period: January 30th 2016 to August 17 2016 (FINISHED)
PoS Phase Period: August 17 2016 onward starting at block 259201 (CURRENT)

Block size: 2 MB
Block Time: 60 Seconds (Re-targeting every block)

Coin Emission Rate: Max. 6 PIV per block (Always less due to burnt fees & unused treasury). 5 PIV are allocated as staking/masternode rewards, and 1 to superblock budget payout.
Coin Supply Control: ALL transaction & zPIV minting fees are burnt from coin supply.

Maximum Coin Supply

At June 2018: 56,550,297 PIV
By June 2020: 62,857,497 PIV

By June 2040: 125,929,497 PIV

By June 2060: 189,001,497 PIV

Theoretical maximum. Will actually be lower due to fee burning + partial budget generation.

PoS Stake Eligibility
Minimum Input Age: 60 blocks
Reward Maturity Confirms: 101 confirms
Wallet Status: Requires wallet to be kept running & online.

Transaction Send Eligibility
Minimum Confirm: 6 confirms
SwiftX Eligibility
1 confirm for locking and 6 confirm to spend.
Collateral held for 15 blocks.

Privacy Technology: Custom Zerocoin Protocol based on libZerocoin (we call this zPIV)
Key Features: Custom accumulator check-pointing system
Accumulator Modulus: RSA-2048
zPIV Denominators: 1, 5, 10, 50, 100, 500, 1000, 5000
Mint time: >= 0.5 seconds
Spend time: >= 2.5 seconds
Maximum single Spend limit: 35,000 PIV
Maximum single Spend denomination count limit: 7
Fees (mint): 0.01 PIV per minted zPIV denomination.
Fees (spend): No fee to spend zPIV back to PIV.
Minimum PIV confirmation count required to mint zPIV: 6 confirmations
Minimum zPIV confirmation count required before spend: 20 confirmations
Maturity requirement before zPIV can be spent: 1 new identical denomination mint added to accumulator

Initial Masternode Coins: (now burnt & no longer exists in coin supply)
[block# 000001] 60,000 PIV for creation of 6 Masternodes for the functioning of the network.
[block# 279917] 60,000 PIV was publicly burned at block 279917.
For more on zPIV and the PIVX Zerocoin protocol see section 6.


2.1 PIVX coin specs cont.


Proof of Work phase rewards breakdown

Block height Masternodes Miner Budget
2-43200 20% (50 PIV) 80% (200 PIV) N/A
43201-151200 20% (50 PIV) 70% (200 PIV) 10% (25 PIV)
151201-259200 45% (22.5 PIV) 45% (22.5 PIV) 10% (5 PIV)


Proof of Stake phase rewards breakdown

Phase Block height Reward Masternodes & Stakers Budget
Phase 1 259201-302399 50 PIV 90% (45 PIV) 10% (5 PIV)
Phase 2 302400-345599 45 PIV 90% (40.5 PIV) 10% (4.5 PIV)
Phase 3 345600-388799 40 PIV 90% (36 PIV) 10% (4 PIV)
Phase 4 388800-431999 35 PIV 90% (31.5 PIV) 10% (3.5 PIV)
Phase 5 432000-475199 30 PIV 90% (27 PIV) 10% (3 PIV)
Phase 6 475200-518399 25 PIV 90% (22.5 PIV) 10% (2.5 PIV)
Phase 7 518400-561599 20 PIV 90% (18 PIV) 10% (2 PIV)
Phase 8 561600-604799 15 PIV 90% (13.5 PIV) 10% (1.5 PIV)
Phase 9 604800-647999 10 PIV 90% (9 PIV) 10% (1 PIV)
Phase 10 648000-1153159 5 PIV 90% (4.5 PIV) 10% (0.5 PIV)
zPoS Phase 1 1153161-Onward 6 PIV 83.33…% (5 PIV) 16.66…% (1 PIV)


2.2 PIVX economics

PIVX, with its intended purpose as a currency, is by design lacking a coin-supply limit. To maintain the health of the dynamic coin supply, PIVX burns its transaction fees. The intention is to encourage liquidity and to reward users for participating in the network. A hard cap will never be reached to prevent the minting of new PIV, and so block rewards will continue to go to those securing the blockchain. This prevents the need to increase transaction fees, thusly supporting the liquidity vital for PIVX to function as a currency.

PIVX now issues about 5 PIV into circulation every minute (6 in total, but treasury allocation and unspent allocation burning decreases this), which is approximately a 4% inflation rate (though contentious, a figure often given as the sweet zone for providing new currency into circulation without triggering hyperinflation is 2-4%, though this figure applies to fiat currencies).
For more on block rewards see section 5.
For more on inflations see section 2.2ii.

2.2 i Dynamic coin supply

Although PIVX features no hard cap on its coin supply (a defined absolute limit), it does have a soft cap (a restriction on the number of coins produced when a certain condition is met). The PIVX soft cap condition is met when fees charged on network actions amount to that minted within a block. The blockchain will then start burning the same amount of coins as it is generating, limiting growth. Thus, PIVX features a dynamic coin supply calibrated by the blockchain in reaction to action of the network.