MimbleWimble is a privacy-oriented blockchain protocol with mysterious origins. Much like other top privacy cryptocurrencies, MimbleWimble attempts to make transactions completely opaque, while still allowing for external verification. 

Additionally, MimbleWimble looks to keep its blockchain’s size on disk as small as possible while maintaining quick verification for all clients.

So far, two privacy cryptocurrencies have launched on top of MimbleWimble technology: Grin and BEAM. 

What is MimbleWimble?

The original MimbleWimble whitepaper was released on July 19, 2016, by an anonymous person that signed the whitepaper as “Tom Elvis Jedusor.”

Just a few months after the release of the original whitepaper, another anonymous person stated that they were working on an implementation of MimbleWimble, which would be known as Grin.

The name “MimbleWimble” and the signing name on the whitepaper are both references to JK Rowling’s Harry Potter novels. Where MimbleWimble is a spell that stops its target from being able to speak coherently. And the name  “Tom Elvis Jedusor” is an anagram for “Je suis Voldemort”, the name chosen by the antagonist in the French version of the novels.

MimbleWimble Goals

MimbleWimble has three goals that are outlined in its whitepaper:

Privacy

MimbleWimble is first and foremost a privacy blockchain protocol. Its designer had a very good understanding of the privacy technologies it is built upon. And using that understanding, MimbleWimble’s designer created a new and more secure strategy that increases transaction privacy to a whole new level. We’ll go into the technical details of this below.

Small Blockchain

Blockchain size on disk is a major issue for those looking to run full nodes for any cryptocurrency. Put simply, blockchains grow. This growth makes maintaining a large number of nodes more problematic over time.

MimbleWimble’s designer saw blockchain size as a major issue and pushed to make MimbleWimble blockchains as small as possible. The whitepaper states that the technique used could reduce the size of Bitcoin blockchains from a size of 80GB to a size of 30GB. An impressive change, especially given that MimbleWimble maintains user privacy through this size reduction.

Quick to Verify

The last goal MimbleWimble aims for is verification speed. Having a tiny blockchain is only good if the processing power required to verify it is equally tiny.

Cryptocurrency Grin launches on MimbleWimble technology

Cryptocurrency BEAM launches on MimbleWimble technology

How does MimbleWimble’s technology work?

MimbleWimble uses its own transaction and block schemes. They work together to hide transaction data as much as possible while still allowing verification to occur.

Put simply, both use zero-knowledge proofs, with blocks building on the math used in the transaction to further hide the information.

No Addresses

MimbleWimble has no concept of a blockchain address. Rather than tying all outputs to an address, outputs have no data regarding where they came from, and are spent via a private key.

This does mean that the wallets of the involved parties wallets have to talk to each other when making a transaction. But the method of communication and time taken is up to the user. One could, for example, negotiate a transaction using encrypted email.

Opaque Transactions

MimbleWimble’s transactions use zero-knowledge proofs (specifically a mixture of Confidential Transactions and CoinJoin) for security. Outside verifiers can independently prove that no cryptocurrency was created or destroyed over the transaction. This is somewhat similar to how Monero secures its transactions, but with added protection from CoinJoin and the total lack of addresses.

Putting together a MimbleWimble transaction requires communication between both parties as discussed above. The following steps are what happens during that communication:

1. The parties agree on the amount to be transferred.

2. The sender picks the inputs they want to use to create the amount to be transferred and adds together all the blinding factors for that transaction.

3. The sender sends the transaction data to the receiver. The receiver then picks the blinding factors for the outputs of the transactions, adds them together, and sends them back to the sender along with any additional required information.

Once the above steps are complete, the transaction can be sent to the network and confirmed.

In the above steps, I mention a blinding factor. The blinding factor makes up part of the zero-knowledge proof system used in Confidential Transactions. It is the ‘missing part’ or the private key for each input – if you know the blinding factor for a given output, you can spend it. By adding together all the blinding factors for every input in the transaction, you can prove you own all the inputs used in the transaction, but not share the private keys.

Reduced blockchain size and increased verification speed

MimbleWimble blocks are different from the blocks employed in other blockchains. Only unspent outputs and new currency generation are saved. The idea being that you don’t need to know about every transaction ever to verify a blockchain. All you need to know is where all the currency is now, and where it all came from.

Storing just that data increases fungibility, user privacy, and verification speed. Much like above, anyone looking to verify the blockchain simply needs to verify that the sum of the inputs subtracted from the sum of the outputs equal zero.

The downside of MimbleWimble

Unfortunately, with the security that MimbleWimble provides, you lose some of the tech Bitcoin has.

For example, in order for all transactions to be consolidated in blocks, they have to be very similar. And due to the requirement for said similarity, MimbleWimble does not have any sort of script system.

Otherwise, due to the consolidation of transactions, MimbleWimble has no transaction history. Meaning that an external auditor or similar would be unable to monitor transactions directly.

Conclusion

MimbleWimble is a fantastic step forward in privacy crypto. If the upcoming launch of its first implementation GRIN goes well, and no issues are found in the algorithm, MimbleWimble will be a serious competitor in the privacy coin market. My only concern is whether or not the inability for even the owners of the currency to audit where it came from using the blockchain itself will deter large scale users.

Sources and further reading:

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binance-cryptocurrency-exchange-dex.jpg-760x400

Binance has launched a fiat-to-crypto exchange on the island of Jersey, a self-governing dependency of the United Kingdom.

Binance Jersey will target those in the UK and Europe, for the first time offering Binance users a way to purchase bitcoin and ethereum with fiat currency (via pound sterling or euros). The new exchange is entirely separate from the original Binance exchange but it will feel familiar to any current users.

Binance is the world’s largest cryptocurrency exchange by volume but currently only facilitates crypto-to-crypto trades. The new Binance Jersey platform will use the same technology to open up channels for fiat pairs.

As is customary for almost any fiat-to-crypto exchange, registering on Binance Jersey requires a Know Your Customer (KYC) identity check before your account is verified.

Much like Malta, the jurisdiction of Jersey has welcomed cryptocurrency and blockchain projects. The island’s regulator, Jersey Financial Services Commission (JFSC), has previously approved the world’s first bitcoin investment fund as well as offering clarity on initial coin offerings (ICOs) and crypto exchange operations.

Further reading: Best Cryptocurrency Exchanges in 2019 (The Most Comprehensive Guide)

Ethereum Constantinople

Ethereum Constantinople is a hard fork of the Ethereum blockchain designed to lay the groundwork for huge scaling improvements.

Originally scheduled for Wednesday 16th January, Ethereum Constantinople has been delayed by developers. A vulnerability was found in the code that could have been exploited by hackers, putting funds at risk.

In a blog on Ethereum.org, the team explained: “Out of an abundance of caution, key stakeholders around the Ethereum community have determined that the best course of action will be to delay the planned Constantinople fork.”

The delay is temporary while developers work towards a solution.

What is Ethereum Constantinople?

The hard fork is part of Ethereum’s long-term scaling road map. Ethereum has long suffered congestion problems which results in high fees and slow transaction times when the network is busy.

The Ethereum team is working on several scaling projects including off-chain solutions, sharding, and, ultimately, a switch to “Proof of Stake” algorithm. Together, these changes should result in significantly higher speeds and lower costs.

However, upgrading the network while operational is like changing the engine in a moving car. The Ethereum team need to lay the technical groundwork before the big changes can happen.

That’s where Ethereum Constantinople comes in. It implements a series of maintenance upgrades that facilitate enormous scaling in the future.

What’s in the upgrade?

Ethereum Constantinople will implement five ethereum improvement proposals (EIPs).  They are as follows:

EIP 145 – Will result in a 91.4% saving in Ethereum gas costs through more efficient information processing methods. It relates to a process known as Bitwise shifting and requires the introduction of a native operation on the Ethereum Virtual Machine (EVM).

EIP 1052 – Makes it cheaper to process large smart contracts that only require a hash.  More specifically, this functionality returns the keccak256 hash of a contract’s bytecode. It improves upon the design of the EXTCODECOPY opcode.

EIP 1283 – This proposal aims to help smart contract developers by reducing gas costs related to changes made to data storage.

EIP 1014Introduces some off-chain transaction solutions to improve scaling possibilities.

EIP 1234 – Delays the “difficulty bomb” and reduces the mining reward from 3 ETH down to 2 ETH.

Of the proposals above, only the last one is considered controversial. Ethereum’s difficulty bomb is designed to make it progressively more difficult to mine Ethereum. At a certain point, it will become almost impossible, forcing the switch from “proof of work” to “proof of stake.”

The proposal exists to de-incentivize miners by not only making it more difficult to mine but by reducing the reward too.

Despite the controversial proposal, mining pools were generally on board with the upgrade. We were not expecting a contentious fork or competing chains.

Ethereum Constantinople Delayed

On Tuesday 15th January, Ethereum developers announced a delay to the upgrade. The decision involved Ethereum founder Vitalik Buterin and other prominent Ethereum developers.

A new date for the upgrade will be discussed on Friday 18th January. 

A Critical Vulnerability Discovered

A vulnerability was discovered in one of the proposals (EIP 1283) by ChainSecurity, a smart contract auditing company. 

The vulnerability would have enabled a “reentrancy attack” against smart contracts similar to the 2016 DAO hack which saw $70 million in ethereum stolen.  

A reentrancy attack means a manipulative actor could theoretically ask the smart contract to perform a specific function multiple times before the contract is executed or anyone is notified. It means an attacker could keep withdrawing money almost endlessly. 

In a detailed Medium post, Chain Security explains:

“The upcoming Constantinople Upgrade for the ethereum network introduces cheaper gas cost for certain SSTORE operations. As an unwanted side effect, this enables reentrancy attacks when using address.transfer(…) or address.send(…) in Solidity smart contracts. Previously these functions were considered reentrancy-safe, which they aren’t any longer.”

Is Ethereum at risk now?

ChainSecurity concluded that the current Ethereum blockchain is currently at risk:

“A scan of the main ethereum blockchain using the data available from eveem.org did not uncover vulnerable smart contracts.”

At the time of writing, the Ethereum Constantinople upgrade is delayed with a new launch date to be discussed on January 18th.

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People love to compare the bitcoin crash to the dot-com bubble.

I get it. It makes a good headline. At the end of 2018, Bloomberg, CNBC, and Fortune were quick to print stories like this:

The Crypto Crash of 2018 Is Now Worse Than the Dotcom Bust

Crypto’s 80% Plunge Is Now Worse Than the Dot-Com Crash

Bitcoin is unfolding like the dot-com crash, just 15 times faster

If you look at bitcoin’s run-up in 2017, it does look worse than the dot-com bubble.

bitcoin vs dot com bubble chart
Source: WSJ

But these charts ignore one crucial thing:

The dot-com bubble was EIGHT times bigger than crypto

We’ll start with market capitalization.

The market cap of the NASDAQ Composite Index (which tracks tech stocks) during the peak of the dot-com boom was $6.7 trillion.

The crypto market cap at its peak was $828 billion.

In other words, the dot-com bubble was eight times bigger than crypto.

crypto market cap vs nasdaq market cap

The absence of Wall Street

The second big difference between the dot-com bubble and the crypto bubble is a complete absence of institutional traders.

Almost no-one on Wall Street was trading bitcoin in 2017. Most family investment offices and hedge funds didn’t hold crypto either.

Whether it’s a good thing or a bad thing, the “big money” hasn’t come to crypto yet. The two bubbles are completely incomparable when the investor base is so widely different.

Bitcoin was a bubble…

Don’t get me wrong. The bitcoin spike in 2017 was a bubble. A big one.

It had all the hallmarks of a big financial bubble: mania, greed, delusion, and capitulation. And the 80% drop is painful.

But if we’re going to put this in context with historic bubbles, let’s use a relative scale, not percentage drops. 

Bitcoin’s “dot-com moment” may yet be still to come

Bitcoin’s “dot-com moment” won’t happen until we see much bigger volumes of money flowing into it.

This infrastructure is building… Nasdaq and NYSE are launching on-ramps for crypto. A bitcoin ETF may be on the horizon. Institutional-grade custody is coming.

Only when these things are in place will we see the kind of money required for a “dot-com” level run-up.

And if that happens, the fall will be truly enormous when it bursts.

A version of this article appeared in our exclusive newsletter. If you’d like Block Explorer’s cutting-edge analysis in your inbox every Tuesday, sign up now.

bitcoin hack how to avoid

New Zealand based crypto exchange, Cryptopia, was hacked on January 14th.

In a statement released on Twitter, Cryptopia said the exchange “suffered a security breach which resulted in significant losses.”

The platform is currently in “maintenance mode” while the team assesses the full scope of the damages. Although no official figures have been released, Larry Cemark, analyst at The Block, suggests as much as $3.5 million worth of ethereum and CENNZ tokens were stolen.

New Zealand police and the High Tech Crimes Unit are currently investigating the breach.

The news comes after $1 billion in cryptocurrency was stolen in 2018. The full Cryptopia statement is below.

Cryptopia Exchange Hack Statement

cryptopia exchange hack