Cryptographer Whitfield Diffie has told the Black Hat Europe conference in Amsterdam that the Internet needs crime.

Diffie is the VP of information security and cryptography at ICANN, who laid the foundation for the public key infrastructure which now helps secure the Internet. Diffie said that good guys can't exist without bad guys and the comment explains the rise of cybercriminals and groups such as Anonymous and LulzSec.

He said that one of the most important things for good cryptography and security in the age of the Internet is good code. Unfortunately, really good code is generally too expensive to write. He said that humanity is moving into a software age as we moved into an iron age.

This means that there needs to be a good plan to secure software. To do that a developer needs to know exactly what the purpose is of the application is going to be to make it more secure. They need to write good code when some of the current programming languages are vastly inaccurate. Some languages actually encourage buffer overflows, Diffie said.

Writing code is almost always a trade off. While in the 1970s it was thought possible to get full formal proof of the code, achieving that is not a realistic scenario, because of the cost involved. He said that all good code is expensive and more money should be spend on writing really good code so applications can become secure, he said.

Browser sandboxes are created to confine code but people need to realise that way of working is inadequate for a lot of applications.