Jackson Blog List
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Over the past 3 ½ years I have written 65 blogs on various Qtum technology topics. With this many titles it is hard to find a particular topic on Medium. For easier reference, this list presents all the blogs with a summary of each.
My personal favorite blog started the series and is still the most viewed — an ELI 5 explanation of how Qtum Proof of Stake works, with a comparison between bitcoin Proof of Work (as a marathon race) and Qtum Proof of Stake (as a stroll in the park).
The 5 most viewed blogs are
An Introduction to Qtum Proof of Stake Mining — A Racing Story — 5.1k Views, how Qtum Proof of Stake works.
Private Keys: Making the Wallet Import Format 4.5k Views, making the WIF (Wallet Import Format) private key from a raw private key.
QRC20 Token Report — February 25, 2018 4.2k Views, how QRC20 tokens work, how an airdrop works.
Qtum Hard Fork, Part 2 4.2k Views, how hard forks work, Qtum hard fork details.
Qtum Full Node: Opening Your Ports 3.2k Views, how Qtum peer-to-peer networking works, how to open port 3888 for incoming traffic.
Enjoy!
2021 Blogs
65. Into the FastLane: Reduced Block Time — Part 4 — March 23, 2021
Qtum Core version 0.20.2 was released on March 18, 2021. This version for the Qtum-Qt and qtumd wallets (the Qtum full node staking wallets) will implement the hard fork for faster block spacing with a hard fork as follows:
- Testnet block 806,600 approximately March 26, approximately 1:00 am GMT
- Mainnet block 845,000 approximately April 30
The new staker provides more efficient staking as soon as Qtum Core is updated. Maturity will change to 2,000 blocks with the hard fork. Some medium-sized super stakers will need additional staking UTXOs.
64. Using Qtum Electrum with Hardware Wallets — March 16, 2021
Using the Qtum Electrum wallet for restoring addresses from hardware wallets to make offline staking address delegation transactions. Delegate addresses held in hardware wallets for offline staking. These transactions can be created with a cold wallet described in the previous blog Qtum Electrum Cold Wallet Staking for additional security. The companion video blog shows the steps and results for recovering and delegating a Trezor address.
63. Into the Fast Lane: Reduced Block Time — Part 3 — March 9, 2021
After months of testing the design has coalesced around 32-second average block spacing with 4-second intervals. The current nodes operate with 128-second average block spacing and 16-second intervals, so the blocks will be running 4 times faster. Other blockchain parameters will be adjusted to maintain consistency: the block reward will be 1.0 QTUM, 2,700 blocks/day, halving on about December 1, 2021, “expected time” will drop by 4 times, TPS remains at 70.
62. Super Staker Status Tool — January 21, 2021
A tool to analyze the UTXOs of the staker and its delegates. How to install Python and run the tool that makes API calls to qtum.info.
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61. Into the Fast Lane: Reduced Block Time — Part 2 — January 12, 2021
Qtum published QIP-26 to reduce block spacing on October 19, 2020. The main goals of this proposal are to reduce the spacing between blocks to speed up transactions, confirmations, and smart contract responses such as for DeFi.
The current testing is focused on a 32-second average block spacing and testing shows that the interval should remain at 4 seconds. The “interval” is a time slot during which the Stakers use the consensus algorithm to check all their UTXOs (their own and delegated UTXOs for Super Stakers). Test results for the new staker.
60. Into the Fast Lane: Reduced Block Time — Part 1 — January 6, 2021
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The strategy and tradeoffs for blockchain speed. The Qtum “Speed-up Plan” will be provided through these main upgrades:
- The average block spacing shortened from 128 seconds to 32 seconds
- Upgrade the difficulty adjustment algorithm
- Modify the block reward
- Improve Staker mining efficiency
Plus, a look at some early test results for faster blocks.
2020 Blogs
59. Offline Staking Update — December 20, 2020
Since the hard fork for offline staking on August 28, 2020, there has been a steady adoption of this new protocol and this report provides an update on offline staking activity and Network Weight. Offline staking has grown since its launch to over half of all block rewards and the Network Weight has grown from 12 million to 22 million.
58. Setting Up a qtumd Super Staker — Part 2 AWS — December 22, 2020
How to set up a qtumd super staker on AWS using a VPS (Virtual Private Server) in the cloud. How to install Qtum on an AWS instance. Using WinSCP to back up the wallet on local storage. Configuration and operating the super staker.
57. Setting Up a qtumd Super Staker — Part 1 Linux — December 7, 2020
How to set up a super staker with the Qtum Core server wallet qtumd, which has a command-line interface, showing two ways to install the wallet, and how to configure it as a super staker.
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56. Qtum Electrum — Cold Wallet Staking — November 12, 2020
Using the Qtum Electrum wallet for offline staking address delegation, including how to use Qtum Electrum to easily split UTXOs and how to use a highly secure cold wallet.
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55. QIP-26: Reduce Block Spacing — October 26, 2020
A review of how GitHub works for code and feature updates, and a close look at the proposed change for reduced block spacing and elaboration on the more developer-focused language in the QIP. Qtum Improvement Proposal 26 suggests reducing the block spacing on the Qtum blockchain, from an average of 128 seconds to an average of 32 seconds (originally 16 seconds). The QIP reviews the motivation, parameters, and issues for reducing the block spacing.
54. Delegating Addresses in Qtum: FAQs — October 4, 2020
Answers for community questions about the details of delegating addresses for offline staking, picking a super staker, splitting UTXOs, etc.
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53. Stake-A-Thon Update #2 — September 26, 2020
Stake-A-Thon metrics with a list of participating super stakers, splitting UTXOs, and a super stakers capacity based on the number of UTXOs.
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52. Hard Fork Special — Linux & Raspberry Pi — September 10, 2020
What happens if you miss a mandatory update before a hard fork and how to recover the Qtum Core wallet on Linux or Raspberry Pi with details about these steps:
- Backup the wallet
- Update to the latest version
- Delete the local blockchain and resync the whole thing or use invalidateblock/reconsiderblock
- Run the zapwallettxes=2 command if needed.
51. Hard Fork Special — Mac — September 9, 2020
What happens if you miss a mandatory update before a hard fork and how to recover the Qtum Core wallet on a Mac with details about these steps:
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- Backup the wallet
- Update to the latest version
- Delete the local blockchain and resync the whole thing or use invalidateblock/reconsiderblock
- Run the zapwallettxes=2 command if needed.
50. You Missed the Hard Fork — Now What? — September 5, 2020
The Qtum Core wallet had a mandatory update for version 0.19.1. Older version wallets are incompatible and were automatically disconnected from mainnet. If your wallet missed the hard fork it would be disconnected from mainnet, but still able to peer with other wallets that missed the hard fork, making up a smaller dying “split chain”. There are two fundamental reasons to not be on the split chain: missing transactions and lost block rewards.
49. Hard Fork Special: Windows — August 29, 2020
Did you miss a mandatory update for a hard fork for your Qtum Core wallet on your Windows computer? Updated wallets made the hard fork automatically, users that don’t update in time saw their wallets disconnected from the main network, are not be able to make transactions, and (for staking wallets) may see their coins staked on a split chain, where they are difficult to recover. This blog gives the steps to update and recover your wallet.
48. Qtum Super Staker: Easy Setup Guide — July 8, 2020
A step-by-step guide on setting up and monitoring the Qtum Core wallets Qtum-Qt and qtumd as a Qtum Super Staker. How to set up a super staker on Testnet in 6 easy steps.
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47. Qtum Testnet Warm-Up for Offline Staking — June 22, 2020
As a warm-up for testing Offline Staking on testnet, here is a review of the Qtum testnet. Use testnet with your existing Qtum wallets to fully explore transactions, block rewards, etc., and after the testnet hard fork, test Super Stakers and address delegation for Offline Staking. Testnet is a great resource for newbies and blockchain developers, and here we put the testnet to the test.
For more on Testnet see #11. Testnet and Qtum Mainnet Performance January 1–8
46. The Road to Offline Staking — Part 3 — Super Staker Wallet Weight — June 11, 2020
A simulation to find the optimal amount of staking QTUM for a Super Staker. The Super Staker must have its own inventory of UTXOs ready to be staked, and locked in a stake for 500 confirmations (blocks — 2,000 after the hard fork on April 30, 2021). We show for a Super Staker managing a large number of delegated UTXOs, how many UTXOs needs for staking.
45. What is a Blockchain Halving: Bitcoin & More — May 2, 2020
Since the bitcoin halving is near, we review the bitcoin halving, how it works, and how halving works for Qtum. The bitcoin halving is near and we review the bitcoin halving, how it works, and how halving works for Qtum. Qtum halvings are on a separate calendar from bitcoin. However, Qtum halvings are also set every 4 years, which is 3,942,000 blocks, with the first halving coming in early December 2021.
44. Qtum Improvement Proposal 25 — The Road to Offline Staking — Part 2 — April 1, 2020
Qtum Improvement Proposals (QIP) are a repository on Qtum GitHub for proposals of new features and functions for Qtum. QIPs can propose user interface improvements, changes in technical parameters, new commands, and opcodes, etc. QIP-25 describes the motivation and how offline staking could work. QIP-25 proposes staking from offline addresses, and this blog explains how that could work.
43. UTXOs in Action — The Road to Offline Staking — Part 1 — March 4, 2020
First in a series of blogs about offline staking. UTXOs (Unspent Transaction Outputs) are the fundamental unit of value on the blockchain and are carefully managed for staking in Qtum Proof of Stake. Large stakes are split into two UTXOs, and smaller stakes can combine many UTXOs. We review the current online staking UTXO approach, which will be tweaked for Qtum offline staking.
42. Qtum Core Update v0.19.0.1 — What’s New? — February 25, 2020
Qtum Core version 0.19.0.1 has numerous updates and features incorporated from the Bitcoin Core wallet of the same version. We look at the updates and what they mean, with two more “block relay only” peers, more Korean and Chinese translations, no more 32-bit version, new commands, and how to install the updated version.
41. Blockchain Developer Acronyms: What Do They Mean? — February 7, 2020
A look at three TLAs (Three Letter Acronyms):
- API — Application Programming Interface
- CLI — Command Line Interface
- RPC — Remote Procedure Call
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These interfaces are used generally for managing software and computer systems and we will review how they are used as powerful low-level methods to control a Qtum Wallet (node) or interface with the Qtum blockchain. The command-line interfaces (API, CLI, RPC) provide granular low-level control of all the commands for the Qtum node. The GUI wallet (Qtum-Qt) exposes most everyday commands through a graphical interface. But developers and stakers can use these command-line tools for everything else, and we see how.
40. New Qtum.info Explorer Features — January 27, 2020
Latest features of the Qtum.info Explorer. Here is a look at these features with some more details for each:
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- Network Overview on the home page
- Staking Information Page
- Transaction Types labeling
- Subscriptions
- Unspent Transactions
- Other Tools and Features
39. How Blockchain Explorers Work — January 10, 2020
Full node wallets can access the entire blockchain but their view is focused on the addresses (private keys) they manage. To see all the transactions and blockchain activity use a blockchain explorer, which is a browser and search engine for the blockchain. Explorers work using a database that holds all the blockchain information in easily searchable tables.
38. Qtum 0.18.2 User Interface Updates — January 3, 2020
The Qtum-Qt GUI wallet has two new color themes available, and a Stake page with a Staking button that is necessary for staking wallets to click to the right to activate staking.
2019 Blogs
37. Qtum on 64-Bit Raspberry Pi — Qtumsetup Menu — December 18, 2019
The new version of Qtum Core 0.18.2 is built for 64-bit execution on Raspberry Pi. How to use a setup menu for the Raspberry Pi, and how to edit the Raspberry Pi configuration file.
36. Qtum Mainnet Hard Fork Results — October 23, 2019
The Qtum Mainnet blockchain completed its first-ever hard fork at block 466,600 on October 17, 2019. After five days of stable operation, the results in block spacing improvements from QIP-9 (Qtum Improvement Proposal #9) can be observed. The hard fork also implemented QIP-5 for the OP_SENDER opcode giving more flexibility in paying transaction fees.
35. Qtum Testnet Hard Fork Results — October 10, 2019
The Qtum Testnet blockchain is available for testing and development and completed its hard fork with Qtum Core wallet version 0.18.1 on September 20, 2019. After two weeks of operation, the results in block spacing improvements from QIP-9 (Qtum Improvement Proposal #9) can be observed. Variance for difficulty and block spacing was reduced and the average block spacing dropped to 128 seconds.
34. Qtum Hard Fork, Part 2 Understanding Qtum’s Hard Fork — September 26, 2019
The upcoming hard fork for Qtum 2.0 will add new smart contract capability, reduce long block spacing and increase the blocks per day, giving staking wallets a 12.5% raise. The hard fork will happen at block 466,600 (October 17, 2019) and only applies to the Qtum Core wallets Qtum-Qt and qtumd, no other wallets. While updated wallets will make the hard fork automatically, users that don’t update in time will see their Qtum Core wallets disconnected from the main network, will not be able to make transactions with exchanges, and (for staking wallets) may see their coins staked on a split chain, where they are difficult to recover.
33. Qtum Hard Fork, Part 1 Understanding different types of forks — September 22, 2019
A review of soft forks, hard forks, and how they work, including the contentious hard fork (creates a new blockchain and new coins) and the consensus hard fork to launch new features (which does not create a new blockchain or new coins).
32. Qtum on the Raspberry Pi 4B — September 2, 2019
The new Raspberry Pi 4B is a highly capable single-board computer. In a variety of benchmarks and Qtum wallet performance tests, the RPi performed well. You can get better performance using a fast SD card and overclocking. The RPi 4B is a low-cost way to run a Qtum node or experiment with this device. The bootstrap file helps blockchain syncing on slow network connections. While this blog focuses on the Raspberry Pi 4B, you can now run Qtum on the full Raspberry Pi product line, from the modest Pi Zero to the high-end 4B.
31. Qtum Version 0.18.0 Overview — August 22, 2019
Qtum version 0.18.0 for the Qtum Core wallet was released on August 16, 2019, the 28th update since Mainnet version 1.0 on September 8, 2017, adding staking improvements, bug fixes, and bitcoin version 0.18 functionality. The main changes are: update staking efficiency. operational improvements from bitcoin version 0.18, Testnet launch icon for Linux, and the preassembled Raspberry Pi images for version 0.18.0 support the full lineup of Raspberry Pis from the Zero to the latest model 4B.
30. Tweaking Qtum Consensus — Deep Dive on QIP-16 — June 7, 2019
Qtum Improvement Proposal #16 suggests changes in the Qtum staking algorithm which could increase returns for staking wallets up to 3 times by time locking their coins. However, improvement in returns depends on what all the other staking wallets can do, as a simulation shows.
29. Qtum Staking Guide: When Block Reward? — May 23, 2019
Since Qtum block rewards are given in a random process, we used several approaches to answer the question “when block reward?” The wallet’s “Expected Time” is a probability term for the long-term average of a random process. Over many block rewards, 63% of the time a wallet will receive a block reward before the Expected Time, but the random process means that block rewards could come much sooner than the Expected Time, or much later.
28. Qtum Full Node: Opening Your Ports — April 16, 2019
What is a Qtum full node, how does the Qtum network use peer-to-peer connections, and how do you override well-meaning firewalls and routers that can block these communications? Ports and networking protocols, the “netstat” network status tool. The Qtum node (Core wallet) will connect with up to 125 peers. The first 10 connections are outbound only. If the router and home network have port 3888 open, the node will accept incoming connections for peers 11 up to 125.
27. Cold Wallets and Safe Send — April 11, 2019
A cold wallet is offline and never touches the internet, which is a very safe way to store cryptocurrencies. This blog explains cold wallet and shows how to set up the Qtum Web Wallet as a cold wallet, and then send coins using “Safe Send”.
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26. Big Transactions — Big Blocks — January 5, 2019
The Qtum block size is currently 2.0 MB (2 megabytes or 2 million bytes), and by looking at all the Mainnet blocks since launch there are some blocks near this size. We review some typical sizes for various transactions, historical block sizes, and attempt to publish a really big 2.0 MB block. Also, a calculation of the theoretical TPS (Transactions Per Second).
2018 Blogs
25. Top 10 Qtum New User Questions — December 8, 2018
Another round of new user questions featuring staking, block rewards, wallets, the “change” address, checking if the wallet is staking correctly, syncing the blockchain, and more.
24. Private Keys: Making the Wallet Import Format — November 12, 2018
An unfortunate user made the usually fatal mistake of sending Qtum to a wrong address but exploring how the Wallet Import Format (WIF) private keys are built allowed recovering these coins. We look at Base58 encoding, the blockchain identification prefix, checksums, and go step-by-step to create a WIF private key.
23. Network Weight — October 31, 2018
Network weight is an estimate by the wallets of the total number of coins being staked by all the wallets and is only used for calculating the time to an expected block reward. How network weight and annual return are related.
22. Wallets and Keys — July 25, 2018
How private keys work with Qtum wallets. How to move private keys and seed words between different wallets. Using the Qtum Web Wallet https://qtumwallet.org/ to restore from other wallets.
21. Orphan Blocks — June 16, 2018
A close look at orphan blocks: what they are, what happens when a staking wallet gets an orphan block, and how can you tell if your wallet got an orphan block. Orphan blocks happen when two nodes publish a new block at similar times. Orphan blocks are perfectly normal and perfectly healthy for decentralized networks. You may see orphan block rewards occasionally before they are canceled out and very occasionally you can use the “zapwallettxes=2” command to fix an orphan block problem.
20. QRC20 Token Update — May 28, 2018
Another deep dive on how Qtum QRC20 tokens work, with a discussion of gas price, gas limit, typical gas fees, and looking at smart contract transactions with the explorer qtum.info.
19. Qtum Peer Connections — May 21, 2018
Qtum nodes are happily chatting away with their “friends” all over the world on Qtum’s peer-to-peer network. This blog looks at how nodes make a “friend request” to peer with other nodes and how to troubleshoot peer connections.
18. Top 10 Qtum New User Questions — April 22, 2018
Inquiring minds want to know about staking, wallets, block rewards, QRC20 tokens, and other Qtum topics.
17. Network Hash Rates — April 4, 2018
A comparison of network hash rate with two Proof of Work coins: bitcoin 25.5 EH/s, Ethereum 256 TH/s, and environmentally-friendly Qtum Proof of Stake at thousands of hashes per second.
16. Newbie Wallets — April 1, 2018
The node map, distribution of nodes by country, research about new wallets.
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15. The Debug Log, the Virtual Machine Log — March 13, 2018
How to find the debug log, how to read it, and how to see problems logged there, and the virtual machine log vm.log which logs actions of the Ethereum Virtual Machine. Typical log events for startup, receiving, and sending coins.
14. QTUM Capped Supply — The Halving — March 4, 2018
How halvings work, a walk-through of the code that controls halvings. The maximum supply of QTUM is capped at 107,822,406.25, reached in 2045. A chart that shows the halvings.
13. QRC20 Token Report — February 25, 2018 — February 25, 2018
A tutorial about Qtum QRC20 tokens: what they are, where they are, how to interact with them, how to watch them, and how they are created and destroyed, how airdrops work.
12. Happy New Year! — Qtum Mainnet Performance — February 16, 2018
Update to Qtum Core v0.14.14. Mainnet reaches block 100,000. Using a simulator to look at network weight and average block spacing (143 seconds).
11. Testnet and Qtum Mainnet Performance January 1–8 — January 7, 2018
Use Qtum Testnet for testing and development. With the Qtum wallets access testnet to explore transactions, block rewards, etc. A Q&A all about testnet, the testnet faucet provides free test QTUM. Charts and graphs for testnet performance.
2017 Blogs
10. Qtum Mainnet Results December 25–31 — December 31, 2017
Why use a VPN? Why it is important to use a VPN with cryptocurrencies. Using a VPN with a Qtum node. Ping (connection) times with and without a VPN.
9. Qtum Mainnet Results December 18–24 — December 24, 2017
The mempool revisited and transaction fees. Fixing the fees for an errant wallet. How transaction fees are calculated. Typical transaction fees and smart contract gas.
8. Qtum Mainnet Results Dec 11–17 — December 17, 2017
How passphrases work. A Python script to enter guesses for a passphrase. Online tools to generate typos for passphrase words.
7. Qtum Mainnet Results Dec 4–10 — December 10, 2017
The memory pool and unconfirmed transactions. Pending transactions on Ethereum because of Crypto Kitties.
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6. Qtum Mainnet Results Nov — 27 — Dec 3 — December 3, 2017
Orphan blocks. Orphans on bitcoin and Blackcoin. Uncles on Ethereum. Orphan blocks on Qtum.
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5. Qtum Mainnet Results November 20–26 — November 26, 2017
Charts and graphs for unique reward addresses, active transactions per day, block spacing variation, and network weight.
4. Qtum Mainnet Results November 13–19 — November 20, 2017
A 100-sided die and a 1.16 x 10 77-sided die. More on difficulty. Spreadsheet for converting bits to target and difficulty.
3. Smaller Staking Wallets — The Rest of Us — November 12, 2017
Block reward results for wallets with < 1,000 QTUM. Network weight and deriving “alternate network weight” using results from big wallets.
2. Target and Difficulty — November 5, 2017
How target and difficulty work. Difficulty bits. Using the SHA256 hash algorithm to produce a result under the target. Simulating difficulty results. Comparison to the limbo game and the Queen of Limbo Meng Jia going under a 65 cm bar.
1. An Introduction to Qtum Proof of Stake Mining — A Racing Story — October 29, 2017
An ELI 5 explanation about how Qtum Proof of Stake works, using a comparison between a marathon (bitcoin Proof of Work mining) and a Qtum “stepping race”. After some introduction, the blog provides more and more detail, ending up reviewing the actual source code that chooses the block publisher and block reward winner.
