A German scientific team gave details of encryption to protect the public in debates over 4 billion mobile phone users.
Karsten Nohl, cooperation with other experts, has spent the last five months, cracking algorithm for encryption technology called GSM.
GSM is the most popular standard for mobile networks worldwide.
The project will listen to anyone – including criminals – in private telephone conversations.
Mr Nohl said the Chaos Communication Congress in Berlin that the project has shown that the GSM security was inadequate .
We try to inform people about the general weakness, he told the BBC.
We expect some additional pressure and customer demand for better encryption to create. The GSM Association (GSMA), which developed the algorithm, and oversees the development of standards, said Nohl project is totally illegal in the United Kingdom and many other countries.
This is not something we take lightly at all, said the spokesman.
Mr. Nohl, told the BBC that he consulted with lawyers before publication, and believes the project was legal.
Mr. Nohl have published work with some dozens of others, the requirements for the material to crack the A5 / 1 algorithm, 22-year-old code from many sources.
The code is designed to force intercepted telephone conversations through mobile phones and base stations change frequencies quickly to a series of 80 channels for prevention.