The World Wide Web Consortium (W3C) has recommended a new standard for digital signatures, but it may be inappropriate for some uses because of its complexity.

XML Signature has been proposed as an XML-based language for digital signatures by the W3C, following collaboration with the Internet Engineering Task Force.

"By offering basic data integrity and authentication tools, XML Signature provides new power for applications that enable trusted transactions of all sorts," said W3C director Tim Berners-Lee.

The W3C explained that the specification is stable, contributes to web interoperability and has been reviewed by the W3C membership which favours its widespread adoption.

The benefit of XML Signature lies in the fact that multiple users can apply signatures to sections of XML, not just whole documents. This means that when XML documents such as invoices are sent through a series of intermediaries, sections of a document can be signed by multiple individuals without invalidating other portions of the document.

But analysts have urged caution in adopting the standard. "Cryptographically applied signatures need some form of public key infrastructure which can add to application costs and complexity," warned Vic Wheatman of analyst firm Gartner.

He advised companies to evaluate whether they need the higher levels of security that cryptographic digital signatures provide. "Other forms of electronic signature might be adequate," he pointed out.

Digital signatures mark a piece of information so that recipients can be sure of the identity of the signatory and the integrity of the information.