AOL on Monday became the first major IM network to open up its platform to third parties with the release of a software development kit and the launch of an Open AIM initiative. The program covers three different areas: plug-ins, online presence and completely custom AIM clients.

AOL has long held aspirations to break down the walls surrounding AIM and invite outsiders to build solutions upon the architecture. The company says the recent launch of AIM Triton -- version 6 of its client software -- has provided the necessary foundation.

"As part of the Triton release, what we've really been doing is creating a platform and an infrastructure that enables third party development," Director of AIM Product Management Jamie Odell told BetaNews.

"It's been a long time in coming and we're ready now. We really want to increase overall value of the AIM network by allowing people to build applications that we never would get to," added Justin Uberti, Chief Architect of AIM. To encourage development, access to the SDK is completely free.

The first piece of the Open AIM effort is expanding presence notification, which displays when an AIM user is online, to any Web site or application. AOL has previously established presence deals with a number of services, and the company is now providing simple HTML and an XML interface for developers interested in adding the functionality.

The second area of focus is building plug-ins that add features to the Triton client directly. Plug-ins could enable users to change their font color on the fly or connect Triton with iTunes and Winamp. AOL has made available a number of example plug-ins, along with their source code, to give developers a head start.

Lastly, AOL wants to encourage companies to build their own customized AIM clients using the SDK. The company recently announced AIM Pro, built with the help of WebEx, as its first custom client. Developers can build their own user interface that utilizes the AIM API.

While the AIM API will be fully exposed through the SDK, source code will not be available. Uberti notes, however, that open source clients can be written atop the APIs. While third party clients have long been able to access the AOL network, their functionality has remained limited due to the AIM protocols being largely closed. This has now changed, says Uberti.

"We're taking the same stuff we're building AIM Triton with, packaging it up and giving it out to the developer community to use for free. Not only access is provided, but a full toolkit including SMS, images, security features, and more."

However, there are some restrictions to the Open AIM licenses. Those who use the APIs to build a custom client cannot connect to multiple IM networks, which means popular software such as Trillian and Adium will not be able to make use of the SDK.

In addition, each license key embedded into a program can only log-in to the AIM network 250,000 times per day, or 2 million times per month, limiting the potential user base. If an application is reaching that level, AOL says developers can approach the company and forge a business partnership.

The Open AIM initiative is specifically focused on consumers, and enterprise customers such as Oracle or SAP must still work with AOL directly. Still, the license does not restrict developers from doing something commercial and AOL expects AIM to show up in new places.

"We're going to see a lot of IM integration," Uberti explained to BetaNews. "We're going to see things where IM is not the primary objective of the application."

Uberti offered some examples of AIM being integrated into video games, or webcam vendors like Logitech building a custom video chat client for their customers. Social networking is also expected to be a major draw; MySpace or Facebook could build an AIM client tied to their social networking experience.

"AIM has lots of users, but more users are even better. Opening up messaging as a platform could bring in more users from more places," remarked Jupiter Research senior analyst Joe Wilcox.

"I see lots of potential uses for AOL's messaging platform. One use: Provide better online safety, assuming third parties would have access to AOL parental controls. AIM presence on services like MySpace or Xanga could let kids show their friends when they are online, but not necessarily broadcast the IM handle to everyone."

AOL wants to promote itself as the premier instant messaging client for doing development. The company is talking to a number of potential partners, but has nothing to announce as of yet. Improvements and follow-up releases of the SDK are also forthcoming, Uberti said.

"What we want to do is get the creativity of the dev community as a whole out there working on things that extend the value of the AIM network and providing them with the best tools we can," he added.