It was 1996 when Fran Rooney, the then CEO of Baltimore Technologies, paid Cryptomathic co-founder Professor Peter Landrock a visit. "At that stage they were smaller than us and they knew nothing about security," says Landrock.

Back then, Cryptomathic was just a modest-sized consultancy, but when security software vendor Baltimore took off, cryptography expert Landrock was stung into action.

Baltimore made its name with public key infrastructure (PKI) software that provides an environment in which large-scale encrypted communication can take place, using digital certificates and digital signatures for authentication of users. "What we predicted long before it happened was that PKI solutions as they were offered by a number of companies were too user-unfriendly," says Landrock.

He set about developing a range of PKI-based products that did not require vast technical expertise on the part of the user. "The traditional approach is to issue people with certificates that they have to review and they have to worry about whether they are revoked and so on. Our solutions check this automatically, without the user having to worry," says Landrock.

Crytomathic's flagship product is the PrimeInk toolkit. This enables application developers to build PKI support into their applications, with customised versions available depending on what kind of application is being deployed.

At the same time, Cryptomathic can offer a range of related products and toolkits targeted at a variety of niche markets, such as mobile payments or secure email systems. The software is aimed at systems integrators and software vendors rather than IT departments.

Cryptomathic also provides the technology behind Beamtrust, a secure mobile payments company that uses mobile phones to store digital signatures and provide an extra level of authentication for a range of transactions. Beamtrust's technology is currently being trialled by automatic teller machine maker NCR.

But however easy to use, there remain question marks over the widespread adoption of PKI. In particular, organisations have found it to be expensive to implement and administer.

But there is no doubting the technical expertise of Landrock and his staff, nor the strength of the company's offerings. The payroll includes Vincent Rijmen, co-developer of the Rijndael encryption standard that was adopted as the advanced encryption standard (AES).

And Landrock himself says he has so far turned down a total of seven takeover offers – although he does not regret turning down the approach from Baltimore.