When we last examined the standards issue about eight months ago, half of all vendors said they were supporting H.323 in some way. That's still true now, but it is clear that competing standards are encroaching on H.323's territory.
From vendor interviews we conducted for this review, we gleaned a general consensus that by year-end 2002, most (more than 50 percent) voice-over-IP equipment will interoperate. However, this clearly will not be based on one standard but many.
Miercom will be testing these claims in our continuing voice-over-IP interoperability labs, the first of which will run at ComNet 2001 in Washington, D.C. this week.
Trend no. 5: Interoperating partnerships
If a voice-over-IP product is going to work with any other vendor's gear in general, that gear is going to be shipped by Cisco. Twenty-eight vendors say they interoperate with Cisco voice-over-IP products, with 10 reporting that interoperability was achieved specifically with Cisco's AS5300 gateway. That's not surprising, considering the prominence of Cisco's voice-over-IP equipment in enterprise and carrier networks.
The second most frequently cited voice-over-IP partner and product was Microsoft's NetMeeting. A few vendors also reported interoperability with Microsoft's Outlook e-mail application.
Lucent was the third most frequently mentioned partner (by six vendors on various products), although this involves equipment that has now largely been assumed by Avaya. Another reference product for achieving interoperability is RADVision's gatekeeper -- the fourth most commonly cited interoperable partner (by five vendors).
About half of the vendor respondents reported they had conducted widespread interoperability trials, but were generally not willing to go on the record with partners' names -- mainly citing nondisclosure agreements for the lack of specifics.
Our assessment of the thorny voice-over-IP interoperability issue is that while we're seeing more willingness among vendors to cite interoperable partners than a year ago, widespread interoperability in the voice-over-IP marketplace doesn't yet exist. Until this interoperability is proven in the public domain, all of the gains voice-over-IP products have made in the past year will be bridled by the fact that making an end-to-end call using this technology is probably not going to work.