MENU

What is Geth?

January 23, 2018
7
18616
0
Understanding how to download and interact with the Ethereum blockchain is a crucial part for anyone learning Ethereum. There are several popular clients to work with the Ethereum blockchain. They are: eth – a client written in C++ geth – a client written in Go pyethapp – a client written in python There’s also Haskell and Java. There is a more detailed description here. Here we will focus on Geth. What is Geth? Geth is a multipurpose command line tool that runs a full Ethereum node implemented in Go. It offers three interfaces: the command line subcommands and options, a Json-rpc server and an interactive console. Downloading Geth There are several ways to download Geth. One is to visit https://geth.ethereum.org/downloads/ and download the latest version suitable for your OS. Another option is to use brew for OSX users. Follow the instructions here. With brew, the steps are essentially: brew tap ethereum/ethereum brew install ethereum What this does is install the geth client at /usr/local/Cellar/ethereum/1.7.3/bin Then you can go to your terminal and run >> geth When you run this command, geth will start downloading the entire blockchain onto your laptop. The location of the chaindata will be shown in the terminal window. […]
Read More ›

Great Siacoin farming tutorial

January 18, 2018
0
6032
0
Here is a great resource from Sia Today (https://sia.today/) on how to get a computer up and running as a host to rent our excess storage on your hard drive. Unfortunately the article doesn’t have the date it was published but it seems like it was mid 2017. There are lots of screenshots, probably a bit too much but this is great for beginners.  
Read More ›

Smart contract workshop #2: Remix and MetaMask

January 14, 2018
0
8809
0
It was great to see the dedicated ones turned up yesterday on a beautiful Saturday morning to learn about MetaMask and Remix and deploy a hello world smart contract. We went through the following topics: Install MetaMask Get some test ether Mixing it up with Remix Hello World Compile and deploy captain! Interactive with your smart contract Understanding the code Bonus code It really was about downloading and installing MetaMask, getting some test ether, opening Remix and deploying 4 lines of code and seeing the contract on the Etherscan. It was great to see some new faces and hopefully the learning by doing is helping those who actually want to get a better understanding of what this technology can do. Next week we’ll be looking at MyEtherWallet (MEW) and also creating professional paper wallets on photographic paper with holographic stickers as souvenirs or gifts or just if you want something physical to tuck under your mattress. There will be a catch up meetup on Tuesday 5:30pm for the city folks. Details of that can be found at: https://www.meetup.com/smartcontracts/events/246629747/ If you missed the meetup but want to check out the topics, visit: https://blockchains.learndot.com/ and connect with us on Telegram: https://t.me/joinchat/G84KThDRZaXOJsxa7oQHmw Catch everyone next week.
Read More ›

Vitalik and Gavin on Craig

January 10, 2018
0
6644
0
I had the opportunity to ask Craig Wright a question last week about BitcoinCash. (He is obviously a BitcoinCash fan). He was also challenged to transfer some funds from block #1 but politely declined. There is a continuous debate on whether he is Satoshi or not and we may never know. He speaks very knowledgeably on subject and is obviously very smart. I can’t help to re-share the short video down below where Gavin shares why he thinks Craig is Satoshi and Vitalik gives a great reason why he isn’t based on signal theory. What gets me though is that if Craig is Satoshi, he would know both methods of proving he is Satoshi as described by Vitalik. The first method would leave no doubt in everyone’s mind. The second option is actually the more clever. It leaves doubt, but keeps him in the lime light. It also gives Satoshi this split personality. A messiah type figure in one realm and a very normal person in the other realm. I still not 100% sure and if I had to guess I would say that Craig is not Satoshi, but there is always more than meets the eye.
Read More ›

Hello World Ethereum Smart Contract

January 4, 2018
0
8291
1
Introduction There are lots of simple Ethereum Hello World tutorials around to cater for everyone’s level. This tutorial builds on a 2016 version by Karl Floersh and attempts to keep things very simple. All that is required to be installed is Meta Mask which is currently a Chrome only plugin and is essentially an Ethereum light client browser plugin. More formally: “MetaMask is a bridge that allows you to visit the distributed web of tomorrow in your browser today. It allows you to run Ethereum dApps right in your browser without running a full Ethereum node.“ Outcome To deploy a hello world smart contract on the Ethereum network. Here is the code. It’s 1 contract consisting of 1 function and 1 event. contract HelloWorld { event log_string(bytes32 log); // Event function () { // Fallback Function log_string("Hello World!"); } } This guide should only take about 10 minutes to follow. Step 1: Install MetaMask In Chrome, search for MetaMask and install it as a plugin. Then create an account and change the network to Ropsten. This is the test network. In order to get some test ether, click “BUY” and click “Ropsten test Faucet”. This will take you to https://faucet.metamask.io/ […]
Read More ›

Smart Contract Workshop #1 – Mist

December 30, 2017
0
6887
1
It was great to see bunch of dedicated people gather at 1st Assembly in Lower Hutt to learn Mist, an Ethereum browser and wallet. The tasks were: Downloading Mist Syncing Mist Saving space Mining test ether Creating new accounts Sending ether between accounts The main challenge was downloading the 8Gb Ropsten testnet blockchain. We had some USB’s to pass around with the testnet blockchain on it, but copying that amount of data took a bit of time. For those interested in the workshop content, you can see what we went through at https://blockchains.learndot.com. Register an account, go through the notes and exercises. The process of doing the task created lots of questions such as: What is the difference between Mist and Ethereum Wallet? How do I change networks? How do I know if it is mining test ether? Where do I put the chaindata file? and many more In the end most managed to sync Mist, mine some test ether and send them between accounts which was great to see. In the coming workshops we’ll be building a Hello World smart contract, learning about tokens and eventually building an EIP20 token. There is no pre-requisite knowledge required because we’ll all end […]
Read More ›

Ethereum Smart Contract Revamp

December 28, 2017
0
7002
1
I’ve been meaning to jump back into smart contracts for a while now and thought what better time than now with so many experts around me. Here is one of the most simplest contracts you can write in Remix, which is an amazing online Solidity IDE written by some Russian Einstein like kid. pragma solidity ^0.4.17; contract light { event TurnLightOn(string thing); function () public { TurnLightOn("We should turn the light on"); } } It should be self explanatory but just in case, all smart contracts need to start with the pragma first line otherwise you’ll get a compilation error. The contract is given a name called light, it generates an event and has a public fall back function. A fall back function is how The DAO hack happened. It is a default function that gets called when no function is specified. Officially “Fallback functions are triggered when the function signature does not match any of the available functions in a Solidity contract.” This was for the hackathon so don’t use this code for real. In remix click the details button and you’ll the commands to deploy the code. Now comes the tricky part! You can’t just copy and paste […]
Read More ›

Symlink Mist data directory to save 52Gb

December 25, 2017
0
6943
0
When you download Mist and try to sync the Ethereum blockchain, your Ethereum folder will be in the following location: Mac: ~/Library/Ethereum Linux: ~/.ethereum Windows: %APPDATA%/Ethereum To save space, you can put your chaindata folder in another location such as a removable USB drive. Above you can see my chaindata folder is actually a symbolic link. To create a symbolic link run this command: > ln -s /Volumes/myUSBdrive/Ethereum/chaindata ~/Library/Ethereum/chaindata What I’ve done is I’ve put my 39Gb chaindata folder on a thumb drive and I’m linking to it. The reason why it’s 8.43Gb is because I haven’t removed test net yet. Testnet is 8.24Gb. Once this is removed, even more space will be saved. The other option is to create a symbolic link to the entire Ethereum folder but this results in an error where Mist is looking for a geth.ipc file which is created upon startup but it can’t because of the symbolic link. This is the easiest and quickest way to have the data directory located in a non default location. This is different to bitcoin-qt where the location can be specified in the configuration file. Ref: https://ethereum.stackexchange.com/questions/3307/in-mist-browser-how-can-i-move-the-data-blockchain-to-another-drive-on-mac-osx    
Read More ›

How to figure out what Hyperledger is

December 21, 2017
0
6232
0
I had the opportunity to explorer the Hyperledger project in more detail and my first impression was: “It is an inter web mess of “stuff” that takes a bit of time to understand. “ It took me a few days to slowly build a picture of what Hyperledger is and my second impression is: “It’s actually pretty neat once you breakdown the various components and there is a lot of potential.” The biggest challenge at the beginning was understanding all the terminology involved. Fabric, Sawtooth, Iroha, Composer, Indy etc, then figuring out how they fit together. Hint: They don’t. The next step involved taking 1 technology and peeling back the layers and understanding the architecture and concepts. If you have a current understanding of blockchains or even bitcoins it helps a lot because you can draw parallels. So what is Hyperledger? Some define Hyperledger by defining what it is not. This is helpful. It is not a company, not a cryptocurrency and not a blockchain. The definition that made sense straight away to me was: “Hyperledger is an umbrella project of open source blockchains and related tools” From here, let’s look at the components and rename them slightly. Platform Fabric: […]
Read More ›

Wellington Blockchain Breakfast

December 7, 2017
0
4988
0
The Blockchain Association of NZ hosted the second Wellington executive blockchain breakfast this morning at the Bolten Hotel. We had a diverse range of people from Kiwibank, MBIE, lawyers from Bell Gully and Wakefield law, blockchain company founders and a few independents as well. It was a great chance to network and connect more on a professional level in a more intimate session and also at a different time of the day. Half way through we played musical chairs and everyone got around to meet and connect with everyone else. It was a buffet breakfast and the private room at the Bolton Hotel was fantastic. Thanks to everyone who turned up and special thanks to Wendy for helping to organise! See you all next year!
Read More ›

Wellington December Blockchain Meetup

December 7, 2017
0
2755
0
We had a wonderful turn out for our last Wellington Blockchain meetup of the year. About 65 people attended and we even had pizza’s and drinks as well! The speakers were great. First we had Steve Lowe from Standards New Zealand talking about TC307. Blockchains will get it’s own ISO number soon!!! Geoff Ward-Marshal from DLA Piper shared the regulatory aspects of ICOs. There was a lot of information to consider. If you think you can raise $5M in 5 minutes and run away with your lambo, think again! Finally we had Jason and David from the NEM who are based in Melbourne and doing a tour of NZ promoting NEM and raising awareness of what NEM can do in the blockchain space.   Thanks to all that came, thanks to the speakers and wishing everyone a wonderful Christmas!
Read More ›

Being Schooled in Digital Signatures

December 3, 2017
0
5050
0
I’ve read so much about digital signatures but still didn’t truly understand what they were. I managed to get a one on one with an engineer cryptographer called Weiwu and it was amazing. It goes something like this: Start of with a message. eg “I own this piece of land at 21 To The Moon Avenue” Hash the message. Let’s call this e. Generate a set of keys. ie a public and private key. Let’s call the private key d Generate a random number k. Sign the message with the function sign(e, d, k). That is pretty much it. To get hands on, try these commands: In OpenSSL – create private/public keys, sign and verify: openssl ecparam -name secp256k1 -genkey -out private.pem openssl ec -in private.pem -pubout -out public.pem echo|set /p=”ABCDEFGHIJKLMNOPQRSTUVWXYZ012345″ > message.dat openssl dgst -ecdsa-with-SHA1 -sign private.pem -out signature.dat message.dat openssl dgst -ecdsa-with-SHA1 -verify public.pem -signature signature.dat message.dat Ref: https://github.com/kmackay/micro-ecc/issues/89
Read More ›

Sydney Blockchain Hackathon Round Up

November 29, 2017
0
4898
0
I had never been to a hackathon before so when I found out one was being held in Sydney I was super excited. It was called Blockathon: The Biggest Blockchain Hackathon in Australia and it was held this past weekend from the 24 -26 November 2017. The great Bokky ran several workshops leading up to the hackathon exploring lots of potential projects. I found it very useful. It was like a pre-hackathon hackathon. Most of us didn’t know each other, had never participated in a hackathon before and were all looking to understand how it worked and if our ideas were even worthy of entering. In the workshop we discussed ideas, some people pitched theirs and some “fluid” teams were formed. We also chilled out and ate pizza too. It really was a pre-hackathon hackathon. Then came the big day. Getting to the Michael Crouch Innovation Centre at the University of New South Wales was a little tricky but not impossible. It is a fabulous space though. Its concept is centred around a presentation space, a manufacturing space and a working space. Very clever! A pull up banner would have been nicer than a whiteboard but I can understand why the whiteboard […]
Read More ›

Sydney Blockchain Day 2 & 3

November 26, 2017
0
4753
0
Day 2 started with delicious waffles (there was more than 4!), and then the teams were right back to it. The mentors wondered around helping teams and experts helped with technical questions. At lunch time there were talks from Gazecoin and NEM. On Sunday, waffles were on again and everyone was building up to the pitch at 4pm. There were 13 teams and each team was given only 4 minutes with a hard stop. It was literally mid sentence hard stop! After the presentations 54 boxes of pizza’s were served with a mix and mingle session while the judges deliberated. When the judges came back everyone waited with anticipation for the results. The winners? CryptoCats. Digital assets on the blockchain. The first runner up was JOE, Javascript On Everything and third place was Strata Blocks. It was an amazing event and was very well organised. After the prize giving there were all sorts of offers of funding and sponsorships offers all round. Congrats to everyone involved.
Read More ›

Sydney Blockathon Day 1

November 24, 2017
0
5612
0
I have never been to a hackathon before so thought I’d volunteer and see what they are like. This one was pretty neat. It started on Friday at 5pm at the University of New South Wales at the Michael Crouch Innovation Centre. After the welcome and  introduction to the mentors and rules it was pizza time! After dinner, it was time to head up stairs and start hacking. All the teams found a space to claim their own and started putting a plan together. Some teams had an idea already, others formulated ideas late into the night. This is Daniel Bar who put this whole amazing event together.  
Read More ›

Jelurida, Nxt, Ardor, Ignis, Mumbo Jumbo

November 22, 2017
0
4135
0
When you first come across new words and logo’s in the crypto space it feels so confusing. It’s also difficult to understand especially when you come across something like this: “The token sale itself will be conducted on the Nxt blockchain platform. JLRDA tokens are not transferable or tradable between accounts and for 1 JLRDA, the crowdsale participant will receive 1 IGNIS at the time of Ardor Genesis Snapshot. For 1 JLRDA token the participants in the IGNIS crowdsale will receive 1 IGNIS coin at the time of the Ardor Genesis Snapshot. The last batch of 100 M JLRDA tokens will be reduced by up to 20 M tokens allocated by Jelurida for promotional and marketing use.” What the heck? Then read this summary here. Even Arthur Penzl who provides updates from the Nxt community states: $NXT, $IGNIS, $ARDR — picking the right one to invest in IS complicated. Hopefully the picture below will help. Jelurida is the over arching corporate identity that owns the IP rights of Nxt. Nxt is a platform written in Java and is it’s own blockchain. Ardor is like Nxt 2.0. It incorporates the fundamental features of Nxt but has extra features such as messaging and voting […]
Read More ›

Sydney Tyro FinTech Hub Ethereum Workshop

November 18, 2017
0
6315
0
It’s Friday night and a bunch of us gather at the Tyro FinTech Hub in the heart of Sydney to talk Ethereum, Hackthons and Crypto. The Tyro FinTechHub opened in March 2015 to act as an exchange for ideas and to provide a place for the country’s most ambitious fintech entrepreneurs to meet and work. It’s basically a shared co-working space in the day time and a place for meetups in the evenings. Bokky is the main driver sharing his experience on Ethereum and on this occasion others contributed by sharing ideas for the Hackathon being held next weekend. There was wine, beer, snacks and of course pizza. The neat thing is that if you have any questions, it’s a good place to come and ask and learn from others more experienced than you. There is another session coming up on Monday where Bokky will be talking about Ethereum wallets and signing and possible a BTT audit.
Read More ›

Double booked Blockchain Event In Sydney

November 15, 2017
0
4877
0
It was unfortunate but a few days ago (the 14th of November) there were 2 huge events on at exactly the same time. First there was a Future of Bitcoin, Ethereum, ICOs & the blockchain panel discussion with special guest Dr Craig Wright beamed in from London which drew ~250 people and then there was the ConsenSys $50M Blockchain Fund + Community Pitches 2 blocks down the road that also drew 250+ people. I ended up going to the panel discussion because I wanted to hear from the self proclaimed Satoshi Nakamoto. The panelist comprised of Dr Craig Wright (Bitcoin Guru), Bok Khoo (Ethereum Guru), Rob Allen (PWC), Lasanka Perera (Independent Reserve) and Tobias Abbey (Investor). Craig was really the main person everyone came to see. He is very polarising and didn’t swear at all this time compared to his talk in Arnhem. He is definitely very knowledgable and despite what people may think, the community is better with him than without. One highlight was when Bokky asked Craig to transfer 0.001 bitcoins from block #1 to him and he would send 10 times more in ether back. Craig declined saying he doesn’t want his money. Craig was generous with his time […]
Read More ›

CryptoWars: Bitcoin v BitcoinCash

November 11, 2017
0
5831
0
It was Friday the 10th of November at 10pm. By accident I checked my Coingecko dashboard and saw BitcoinCash hit $700USD, then $750, then $800. It was crazy. Something was up. I proceeded to jump on the various reddit channels, check the #bitcoincash hashtag on twitter and read the various online forums. There was excitement in the air. Something was up. BitcoinCash hovered just below $900 before I went to bed but then on Saturday morning it broke the $1000 barrier. It really was like a roller coaster. Shooting up and then coming slightly down, then shooting up again. It just kept going up as Bitcoin went down. It was a zero sum game. For one to win, the other had to lose. The crypto war is on. Very sad to see #Bitcoin v #BitcoinCash. It should be #Crypto v #Fiat. The human drive for money and power transcends all realms. #SadToSee pic.twitter.com/IhSEFkDkFL — Sean (@seandotau) November 12, 2017 For me, I thought all along that it was Crypto versus Fiat. Us versus them. Guess this is what happens a group of people who have control over large amounts of wealth (in the crypto space) and access to large amounts […]
Read More ›

Melbourne Blockchain Centre

November 7, 2017
0
6274
0
I had the opportunity to visit the Blockchain Centre in Melbourne that I had heard so much about. It’s in the heart of Melbourne in South Bank, not far from the Crown casino. It offers co-working space in the day time and a meetup space in the evening time. The other times are spent expanding the Blockchain Centre franchise model. There’s a “museum” of bitcoin miners but the neatest part for me was Satoshi’s whitepaper enlarged  and hung on the wall. That was cool! The space is very new and officially opens this week.    On this particular evening there was also a packed (photo below was pre-arrival) Crypto Traders meetup which was absolutely fascinating. The presenter introduced all these Japanese terms, eg Kijunsen, and how to trade purely from looking at charts and understanding. It was an amazing learning opportunity. There are several meetups each week where generally Monday is for cryptotraders, Tuesday Ethereum, Wednesday Blockchains and Thursday privacy and security related. One benefit is that all these meetups converge at this one place. It provides a great consistency with a menu of evening learning & education and connecting & sharing which is great to see.
Read More ›