Google's latest offering, the Web-based real-time collaboration suite dubbed Wave, began life in Sydney, Australia, as a start-up project built with Google's open source Web Toolkit project.

Wave's engineering lead Lars Rasmussen said a mixture of software components were used to create Wave, including public and proprietary tools.

For the interface, Google Web Toolkit was used, which turns Java code into HTML, JavaScript and CSS.

“We used it from day one and it is an amazing tool,” Rasmussen said. “Then on the backend we use software that is proprietary to Google.”

Google Web Toolkit is licensed under the Apache 2.0 open source license and includes other open source components licensed under the GNU GPL and Mozilla Public Licence.

Rasmussen lived in Sydney when he started the now popular Google Maps service, which, at the time, pushed the limits of what was available as a Web application.

The Google Wave service has proprietary components, but that isn't stopping the company from releasing a public protocol for Wave server development aimed at allowing third-party Wave “clones”.

From what began as a small team of people, Wave now has 50 staff assigned to it after first being pitched to “Larry, Sergei and Eric” in late 2006.

“We hope that Wave will integrate between systems and developers are already building bridges to other services like Twitter,” Rasmussen said.

In many ways Wave fulfills Rasmussen's 2005 prophecy that more desktop-like functionality will be available to Web applications.

Indeed, the product's codename “walkabout” is mean to signify pushing the boundaries of what can be accomplished in a Web app.

One technology that wasn't around when Web apps began to appear was HTML 5 which Wave is designed to leverage.

Rasmussen said functionality like drag-and-drop and persistent storage will be leveraged from HTML 5.

While dragging a file from the desktop to Wave is not you supported by HTML 5, Rasmussen hopes that will become standardised as well.

For security, files that are specifically dropped are only uploaded to the Wave server and there is software on the server to detect and stop the proliferation of any malware.

As always, browser compatibility remains a challenge for complex Web apps like Wave, but Rasmussen said compatibility is “better in some than in others”.

“The IE story is not so bright and due to its limits we won't support IE 6,” he said, adding IE 7 support is coming soon.

For now, developers will need to access Wave with either Firefox or Webkit-based browsers like Safari and Google's own Chrome.

Rasmussen stopped short of saying Wave will go head on with existing collaboration software from the big-name vendors but is confident it can increase operational efficiency.

“We use it and it makes us more productive,” he said. “We have just scratched the surface at to what is possible with this technology.”

An interesting aspect of the Wave protocol is “concurrency control” which resolves conflicts on the fly when multiple parties are editing the same file.

“Live concurrent editing is not new, but mixing rich content is,” Rasmussen said, adding he doesn't know how well Wave will be received but can imagine a lot of use cases.

“Wave can be used for easy photo sharing, collaboration and integration with workflow tools,” he said.

For now Wave is in “developer preview” mode with consumer accounts expected to available later this year.