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I was piqued by this until I realized it was an advertisement for SIP. SIP has its own set of problems.


When Good Standards Go Bad

August 23, 1999 By DAVID WILLIS

Sometimes there’s just no turning back: When the raft is in the rapids, the skis are at 45 degrees, or the tattoo gun is halfway through your sweetie’s name, all you can do is plow ahead. That’s where the VoIP (voice over IP) industry is with H.323, but behind the scenes vendors and users are beginning to question the choice.

Everybody loves standards. They promise interoperability, freedom from the tyranny of closed systems, greater choice for the customer and lower cost of ownership. Criticizing standards is like censuring democracy and capitalism. But the wrong standard can stagnate an entire industry.

The first version of H.323 is now more than three years old. Version 2 has been out for 18 months, yet the few products claiming compliance still lack features essential to practical use–namely encryption, advanced call control and network-based call management. Microsoft’s latest Windows NetMeeting 3 still can’t claim more than partial compliance, and it is the industry’s most used PC desktop end point. H.323 stacks are available, but only from a handful of vendors. And don’t look now, but version 3 is just around the corner. The H.323 standards are further ahead of the market than any other technology since ATM, and for the same reason: The market doesn’t understand them.

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 (, 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 [at] nwc [dot] com. —