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H.323 makes for good voice calling in the same way that Sumo wrestlers make good jockeys. I'm not claiming that H.323 has any architectural flaws, just that it produces bloated products. I can only comment on what I've seen it do to a network, on bugs found in H.323 implementations and on the painfully slow process of getting vendors to fix them. The promise of opening up advanced PBX call-handling features using H.323 simply isn't being met. IP-based PBX vendors can't even forward calls between each other's products, for example.

Without a doubt, vendors are devoting some attention to interoperability, with many very smart people endeavoring to make this stuff work. More than 30 vendors have pledged support for the iNow! Profile (www.imtc.org/act_inow.htm), which plans to bring about Internet telephony interoperability using H.323 version 2. But the profile was published more than four months ago and the implementation dates are still fuzzy. iNow! isn't that ambitious anyway--it doesn't address call privacy, gateway-to-gatekeeper interoperability, phone-to-PC/device service, roaming or SS7 integration. Where iNow! will succeed is in gateway-to-gateway and phone-to-phone connections--in other words, in providing transmission services in the middle of the network. It won't help at the end points, where we're still waiting for real innovation.

VoIP should run on Internet time, but H.323 is still dialing into Prodigy at 300 baud. Long-distance cost reductions are only a short-term reason to use VoIP, and when that opportunity dries up, H.323 will have no future. Long-term, innovative applications at the end points will drive VoIP. These applications must be easy to create by a wide range of developers, and H.323 won't deliver. It's not optimized for real networks, it's too difficult to develop and it requires too many resources at the client. The specification is further burdened by video and whiteboarding services. H.323 has more oversized baggage than the Augusta airport a week before the Masters.

Do an end run around all the H.323 marketing, and product engineers will tell you that they're waiting for something better. A number of efforts aim to simplify VoIP development, some with amazing success. Four weeks after the IETF's SIP RFC (Session Initiation Protocol-RFC 2543) was published, 18 vendors demonstrated some level of interoperability. Columbia University students have even built SIP implementations as homework assignments. It's exciting stuff, and I'll be digging into it in more detail in my next column.

Send your comments on this column to David Willis at dwillis@nwc.com.