A computer program product for providing authentication to control access to a computer system, the product comprising a computer readable memory and a computer program comprising:
- first computer code receiving at least one first input from at least one measuring device formed as part of a mobile computing and/or communication device;
- second computer code for comparing said first input to a previously measured and recorded input;
- and
- third computer code for determining if said first input is equivalent to said previously measured and recorded input, subject to predetermined error factors, permitting access to a first computer system.