Signatures in tune with the digital age

KEY TO THE FUTURE: James Catchpole and Simon Walker on protecting documents

The use of signatures is a crucial aspect of the contractual interaction of society, and has been so for hundreds of years.

Electronic signatures are the digital equivalent of the more traditional analogue version.

They are a method by which one may authenticate and certify data and electronic documents, and come in a variety of forms, from scanned hand-written signatures and PIN numbers to digital signatures, and encompass the use of encryption technologies and external certification authorities.

The most secure method of electronic signature is currently the use of asymmetric public/private key encryption (digital signatures) with an external certification procedure.

Using sophisticated mathematics, the technique allows for the use of separate keys for encryption and decryption.

Each user, that is the recipient and sender, generates his own pair of keys.

The private key, known only to the signatory, encrypts the data and creates a digital signature that is appended to the data to be sent.

The recipient will then use the sender's public key (sent with the data, but without comprising its security) to regenerate the data and the digital signature to verify that the data has not been altered in transit.

Protection may also be gained through the use of trusted third party certification authorities, which verify the identity of the sender.

A question mark still hangs over the enforceability of electronic signatures within the UK.

While the Electronic Communications Act 2000 does not say that electronic signatures satisfy all legal requirements when documents need to be signed, it does grant such signatures equal evidentiary weight as hand-written ones.

Additionally, an electronic signature can be used as evidence of the authority or integrity of electronic data.

It now remains for the courts to offer guidance on how to use electronic signatures correctly.

The Cabinet Office has commissioned a review to prioritise the legislation requiring amendment in the light of the Act.

This is not easy; it is estimated that there are some 40,000 uses of words that relate to the physically written word within the UK legislation.

Hopes that the EU's Electronic Signatures Directive will be fully implemented by July 2001, thereby facilitating this task, have faded with the onset of the general election.

When the directive is finally implemented in the UK, electronic signatures that satisfy certain criteria should meet all legal requirements for a signature in relation to electronic data and will be able to be used in place of most documents that need to be signed.

The recognition of electronic signatures will be crucial to realising e-commerce's potential.

Without granting them legal validity, the authenticity, integrity and enforceability of electronic transactions will not be assured.

Electronic signatures will be important in securing trust in e-contracting and in determining the viability of e-commerce.

James Catchpole is a member of the IP, IT and digital business group, and Simon Walker is head of e-business, at Landwell UK