When a blockchain forks, the new chain is often seen as an improvement over the existing one. The loyalties of the developers and crypto communities may be divided, but failure to come to consensus will result in a forked chain.

Stress Test Breaks BSV

This is exactly what happened to Bitcoin Cash last week and the fallout has not been pretty as it appears that both blockchains are having major technical issues. The first problem was a bug in the Bitcoin Cash SV chain. Now called BSV, the big block Craig Wright version of BCH suffered what has been termed a ‘block reorganization’ whereby transactions on two different blocks were overwritten.

It turns out that a stress testing group intentionally overloaded the BSV blockchain in order to test network capacity. Instead of resulting in a successful demonstration of the new chain, the 24 million transactions actually spurred a new fork as synchronization between nodes went awry according to reports. The issue has now been resolved but it is not the best of starts for a blockchain that was supposed to be superior to the one that spawned it.

Code Update Endangers BCH

The rival chain, Bitcoin Cash ABC, which is commonly known just as BCH, rolled out a software update that put the entire network at risk of a 51% attack. According to TNW the BCH developers introduced code which alters the way the network enforces trust in submitted transactions.

Just like its big brother, Bitcoin, BCH uses a proof of work consensus mechanism. But with the introduction of the update and ‘checkpoints’, miners were able to check that they were working on the valid chain. The notion was to protect the chain from attacks whereby miners can take over the network by focusing on an alternative chain.

The new system was designed to use the tenth block as a test for accuracy but this has drawn criticism from industry insiders;

ABC officially abandons proof of work. Devs decide the correct chain. Also it's now easy to forcibly hard fork the network by causing a 10-deep reorg. Next up, Bitcoin ABCD! https://t.co/GiEv4ZzCrV — Bob McElrath (@BobMcElrath) November 21, 2018

Miners could now use this tenth block vulnerability to force another chain split for as little as $27,000 with a standard crypto miner according to the report.

Coinbase was concerned enough to suspend trading for both forks as it posted a couple of days ago;

“For Coinbase.com and the iOS and Android apps, we will continue to evaluate the safety of the network before re-enabling buys, sells, sends, and receives. We expect that to occur within the next week. We will resume all BCH services when it is safe for our customers. We will continue to evaluate the safety of the BCH SV chain. Our current intention is to support withdrawal services for the BCH SV chain so that our customers may withdraw funds at a future date. We anticipate this development work will take at least a few weeks, but may take longer.”

At the time of writing Bitcoin Cash, the ABC version closest to the original, has dumped almost 50% over the past week. The constant ‘hash wars’ and infighting on social media has also been partially blamed for the recent market dump by a number of observers.

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