Applications /

SIMPLE, but more complex

By James Kobielus
Network World, 10/08/01

The instant-messaging interoperability wars are far from over, but the smoke is beginning to clear from some of the nastier standards battles. During the past few months, the nascent IM industry has begun to rally around an emerging Internet Engineering Task Force standard known as SIMPLE - an ironic acronym that stands for the specification's complex name: Session Initiation Protocol for IM and Presence Leveraging Extensions. SIMPLE is based on SIP, a signaling and presence protocol used to establish Internet phone calls, multimedia conferences, chat sessions and interactive communications.

SIMPLE is the IM industry's leading candidate for a universal standard, thanks to several recent industry developments. First, the IETF formed a working group earlier this year to develop the specification into an open standard, using prior work by the older Instant Messaging and Presence Protocol working group. Then, during the summer, AOL Time Warner publicly committed to implementing SIMPLE in its AOL Instant Messenger (AIM) service gateway to third-party IM services and products. For its part, Microsoft announced it is implementing SIMPLE in its Windows XP and .Net products. Other IM industry players have followed AOL's and Microsoft's lead, voicing their general support for SIMPLE, although few have announced SIMPLE-compliant products.

Clearly, AOL's and Microsoft's decisions to support SIMPLE swung marketplace momentum toward this emerging standard. AOL's support was especially critical, given its predominance in today's IM marketplace. It has held the industry at bay for the past three years by refusing to interconnect its IM services with third-party IM offerings unless those vendors license AOL's proprietary technical interfaces. Now AOL has opened the door to third-party interconnection through a SIMPLE gateway, which it has just begun to test with Lotus, a longtime AIM licensee.

These are positive developments to be sure, but we're still a long way from true interoperability in the IM market. SIMPLE is not yet a formal IETF standard and has yet to be implemented in any commercial IM products or services. SIMPLE will be implemented in the Windows Messenger component of the forthcoming Windows XP desktop, but Microsoft hasn't indicated when its MSN and Exchange IM servers will be upgraded to support SIMPLE, so it's not clear what value XP's SIMPLE interface will provide out of the box. Indeed, AOL and Microsoft have not publicly stated whether or when they plan to phase out their proprietary IM/presence protocols in favor of SIMPLE.

Where interoperability is concerned, the IM world is a deep quagmire. The industry is still in the prestandards era, much the same situation in which the e-mail industry found itself 10 years ago, before Simple Mail Transfer Protocol was adopted universally. The IM market suffers from a surfeit of proprietary protocols, and no interoperability specifications has yet achieved broad adoption in the marketplace. Until the major IM product and service providers implement SIMPLE natively, we will not have true, any-to-any, backbone IM interoperability.

IM and presence cannot be truly enterprise-grade services until the industry converges on open interoperability specifications. Until then, companies will have to explore second-best solutions. Consequently, the premium for the next several years will continue to be on partial interoperability solutions among diverse IM/presence environments. One approach is to implement "multiservice clients" that can access several incompatible IM services concurrently. Another is to deploy "IM softswitches" for server-to-server bridging.

The bottom line, then, is SIMPLE will not appreciably simplify the interoperability outlook in the IM world for another two to three years, at the earliest. The installed base remains Balkanized among diverse, incompatible, vendor-proprietary protocols, and SIMPLE just adds another pattern to an already-crazy quilt.