For all the attention paid to bitcoin, it is his rival ether to hit the headlines, with the popularity of his blockchain Ethereum technology that motivates the concerns they have sent fleeing investors.
Virtual currencies This month, after US investment banking giant Goldman Sachs withdrew from his plans to open a bitcoin trading desk, a damaging feeling for the entire industry.
Ether slipped 20% in value, obtaining further success from comments made by Vitalik Buterin, co-founder of Ethereum, which fuels cryptocurrency.
At the beginning of this month, the 24-year-old Russian-Canadian programmer told Bloomberg that "the space of the blockchain (Ethereum) is coming to the point where there is a ceiling in sight".
A blockchain is essentially a ledger for transaction registration, which is open to all those who use it, but extremely secure, and has allowed the rise of cryptocurrency trading.  Billionaire thanks to Ethereum, Buterin has already talked about "scalability", probably the first challenge in the industry.
– Blockchain traffic jam –
Unlike bitcoin blockchain, which carries out transactions that only involve cryptocurrency, Ethereum can host several virtual tokens and also enable some digital applications and so-called smart contracts.
Such programs can, for example, automatically activate payments without the use of a third party when predefined conditions are met, such as winning a bet sport.
Ethereum is also home to two-thirds of initial coin offerings (ICOs), essentially a fundraising tool for companies that issue tokens against cryptocurrencies, just like the issuance of shares on a stock market.
An explosion in the number of ICOs in 2017, two years after the launch of ether, led the price of cryptocurrency to plunge 160 times in value over a 12 month period.
Mania surro Indian ICOs have also caused congestion of the Ethereum network, contributing to the collapse of the prices of ether starting in January.
"The more it is required, the more likely it is to clog the network," said Jerome de Tychey, president of Asseth, an association promoting the use of Ethereum.
A clogged Ethereum translates into more burdens for customers who wish to prioritize their transactions – and average expenses briefly hit a record of $ 5.50 in July according to bitinfocharts.com. Generally, however, taxes fluctuate around a few cents.
The delays of a planned review of the scalability of Ethereum have meanwhile probably deterred some investors from using the blockchain, according to de Tychey.
Naeem Aslam, an analyst at the Think Markets dealers, said Buterin "is not doing the job he should do" – that is, making sure that companies "trust the technology and provide them with (what) they have need".
– Virtual currency, true dive –  The dip in the value of the ether was really dramatic. From the beginning of August, it lost more than half its value.
Returning to May, the decline is 75%, with the total value of virtual currency plunging to around $ 23 billion from $ 82.5 billion.
The huge decline only brought the ether back to just over a year ago, at around $ 220 for a token.
Another factor that weighed on the price of the ether was the success of the ICOs. Companies that have raised funds in the air with ICO must now sell them to cover operating expenses in legal currencies.
According to industry analysts Diar companies that raised funds before the price boom at the end of last year sold some 20% of their holdings in ether from April, whose price is in decline.
© 2018 AFP