Silicon Valley firm Verayo is claiming to have produced a system that provides RFID chips which cannot be cloned.

The company uses technology called Physically Unclonable Functions (PUF) that was developed by researchers at MIT.

It uses minute differences in the silicon used in RFID chips to make them individually recognisable.

"PUF technology is one of the latest breakthroughs in semiconductor security, " said the company.

"PUFs are tiny electrical circuit primitives that exploit the unavoidable IC fabrication process variations to generate unlimited numbers of unique, unpredictable, though reliable 'secrets' from each chip.

"Since it is impossible to model or duplicate the IC fabrication process variations, even for the IC manufacturer, it is impossible to generate the same challenge response pairs from another chip."

When queried by an RFID reader the chip will broadcast a 64-bit string of numbers and letters that identifies it exactly.

The technology is being used in Verayo's first commercial product, the VERA X1 RFID tag.

This stores 512 bits of read-only data and the company envisages it being used in security passes and for anti-counterfeiting operations.

Existing RFID readers will be able to operate with the new chips but a firmware update will be required. The company will officially launch the chips next week.