Zcash's privacy may be compromised with certain usage patterns, according to study

A research team at University College London conducted a study on the privacy of transactions of the Zcash cryptocurrency, and has identified patterns in certain types of transactions that weaken the anonymity of the network.

The authors of the study are Haaron Yousaf, George Kappos, Mary Maller and Sarah Meiklejohn, revealed that when addresses go from the state 'unprotected' to 'protected' and back to 'unprotected' addresses, they lose much of the promised privacy to the users of Zcash. In fact, in the study they assure that due to this fact the anonymity of the network can be reduced up to 69.1 percent.

Zcash is currently one of the most promising cryptocurrencies in relation to privacy, offering two types of addresses, the 't-addresses' or addresses without protection, where balances and transactions are public in the chain of blocks; and the 'z-addresses', or protected addresses, where the balances or transactions are private.

As in the Bitcoin network, transactions from one unprotected address to another are fully public. On the other hand, transactions from one protected address to another are practically 'invisible', since only time stamps and fees for mining are shown.

However, the document reveals that transactions between different types of addresses cause problems, since it is possible to obtain certain data from the protected addresses. The reason for this seems to be the regular use of the network by the users.

In this sense, the researchers assure that the fact that the creators of the network always withdraw the same amount of cryptocurrencies in the same time intervals made it possible to detect the pattern. These transactions are made because Zcash is needed to move to the protected group of the 'z-addresses' before they can be used for another transaction.

The researchers said that the developers of Zcash have already been alerted about this problem before the study was published, and affirm that in fact, changes in the network are already being noticed.

For his part, Zooko Wilcox, founder of Zcash, congratulated the experts and emphasized the importance of understanding the loss of privacy of the network by using protected addresses as a transfer mechanism. He also recommended that users store their cryptocurrencies in a protected address.