Airbitz and the Bitcoin Fork
By: Paul Puey
Tags: Blockchain, Wallets, Airbitz, Hard Fork, Bitcoin

As many have heard, the Bitcoin community is engaged a major debate which could cause the bitcoin network to split into two currencies. As a decentralized currency, Bitcoin achieves consensus by hundreds of computers agreeing on a set of transaction rules. These computers confirm transactions on a blockchain, a series of bundled transactions that have been validated by bitcoin miners who have put significant amount of computing power to confirm these transactions.

The current transaction rules put a limit of 1MB on the size of transaction blocks which creates an approximate limit of 3–6 transactions per second on the network. Due to the significant increase in global demand for bitcoin, the network has hit this limit and users are experiencing a noticeable delay in transaction confirmation times and increased mining fees from about $0.10 6 months ago to over $0.50 per transaction (possibly higher) as of this writing.

Two solutions are being proposed to help scale the network. Currently the majority of the Bitcoin network runs an implementation called Bitcoin Core which enforces the 1MB limit. Bitcoin Core proposes an upcoming scaling solution called Segregated Witness which will help decrease the size of transactions once widely supported by most wallets. A second proposal wants to simply increase the 1MB limit. Proponents of this proposal are operating an implementation of Bitcoin referred to as Bitcoin Unlimited, which provides a mechanism for the blocksize to grow beyond the 1MB limit.

Both of these proposals would change the network consensus rules and would activate once each achieves a significant majority of the network mining power.

At Airbitz, we do not take a stance on preferring one implementation of bitcoin over another. Instead, we believe the industry needs both bigger blocks, like Bitcoin Unlimited proposes, and scaling solutions, such as Segregated Witness from Bitcoin Core. These two scaling solutions are not mutually exclusive, and the frustrations held by most of the community we have talked to are around the stubbornness and uncompromising attitude taken by both sides. It has been disheartening to see such a unified effort that aimed to disrupt the biggest industry in the world, now rife with infighting and disagreements, well before it even made a dent in the current financial system. We hope that the lead developers and project managers of both implementations realize there is far more to gain by compromising their stubbornness and re-unifying bitcoin, than there is in keeping the industry divided which adds even more confusion to an already challenging technology to understand.

As these two proposals differ in their ruleset, there is a possibility that the Bitcoin network would split into two chains, with two different rulesets, and two different sets of transactions and balances for each user after the split.

The Bitcoin protocol is designed such that the currently valid transactions, balances, and protocol rules are defined by the “strongest chain”. This is the blockchain that has both the longest chain of transactions and the most amount of mining power. Currently, Bitcoin Core has the most amount of mining power at about 70% of the network, and hence it currently defines the network consensus rules such as the 1MB block size. Should Bitcoin Unlimited achieve 75% majority of mining power, it would become the “strongest chain” and define the rules for the network. By default, light-client wallets (SPV) and mobile wallets like Airbitz, are designed to follow the strongest chain. Therefore, they would not be able to recognize or send transactions on the “weaker” chain. Supporting transactions on the weaker chain requires targeted engineering changes to wallets that would be contrary to the default consensus rules. The Bitcoin protocol makes survival of the weaker chain very challenging as a sudden decrease in mining power will cause significant delays in block confirmation times, and significantly impact wallets, exchanges, and payment processors utilizing the weaker chain.

Fundamentally, we at Airbitz believe that a fork in the Bitcoin network is both unlikely to happen, and unlikely to result in the continued existence of the weaker chain. First of all, it is a huge political challenge for Bitcoin Unlimited to achieve a 75% majority of the mining power in the midst of a contentious debate.. Second, if the 75% majority is achieved, it would put the weaker chain at a significant disadvantage by causing significantly increased confirmation times and dropped transactions. This would likely end its existence allowing bitcoin to continue as one currency, chain, and protocol.

In order to achieve the benefits of retaining access to both chains, as enumerated in the previous paragraph, Airbitz users should complete the following steps a few days prior to the network fork:

Go into Airbitz and copy an address in your wallet from the Request screen. Go to Send, tap Address and paste the address. Tap [Max] and send all your bitcoin to the new address. This will show a transaction that only amounts to the mining fee of the transaction, even though you sent your entire balance. This is because you just sent it to yourself. From here, do not send any transactions before the split. If after the split, the network settles down into one chain, then there is nothing for you to do. You can spend your bitcoin as normal. Should two chains survive and you wish to own the coins on the weaker chain, you can extract the private key with all your funds from Airbitz and import it into a wallet that supports the weaker chain (ie. Bitcoin Core). In Airbitz, go to Wallets -> Export (icon) -> Wallet Private Seed -> View. Write down the private seed. Go to airbitz.co/recovery and enter your private seed. Technical users can go to github.com/Airbitz/airbitz-recovery and download the recovery tool for use on their local computer. You will see a list of addresses and balances show up on screen. Choose the address with your full balance and show the private key. To claim coins on both chains, do the following: Sweep the private key from Step 9 using Bitcoin Core AT THE SAME TIME as you do a Max send to yourself in Airbitz (step 3 above). Once the transactions confirm, you’ll have roughly the same amount of coins on both the Bitcoin Core wallet and Airbitz, each representing bitcoin on each of the different chains.

Should two chains continue to persist after the fork, Airbitz will consider implementing a multi-currency solution in Airbitz that would allow users to hold, send, and receive each of the separate bitcoins as separate wallets in their account.

If you would like to keep up to date on the status of the bitcoin network, Airbitz updates, or receive a notification before the pending network fork, please sign up to our email list at the bottom of our page at airbitz.co.

Thanks

Paul Puey

CEO / Co-founder