Mike, you identified a half dozen stones, and to uncover what those stones are hiding would require a thesis. I'll keep it short.
The promise of IP voice has to do with presence, essentially. It would allow for a form of follow-me on steroids and provide the same kind of functionality as ICU/Instant Messenger capabilities today on the 'Net via PC. In theory, these would be incremental benefits to those already allowed by POTS and cellular services today.
And then there are the always-touted future "converged" data/multimedia/voice applications we keep hearing about that will surface when the gods give their nod.
Wireless voice and voip are not to be considered mutually exclusive going forward, although the promise of IP voice in all of its glory is still a ways off, even on the most advanced wireless platforms. But we shouldn't view them as competing, since future wireless will support it, too.
I don't know why the age of the ILECs should be a factor here. They are likely to be among the first to be able to afford the advanced systems (both access/air-interface side and OSS) that will be required to support a fully integrated IP Voice rollout over wireless.
VoDSL? This is primarily a business class adaptation of voice over dsl supported by ATM-enabled DSLAMs. Residential DSLAMs do not support it, because of the 1999 FCC decision concerning ILEC DSL, and how it would go unbundled. In short, the ILECs are using a modified form of ATM, not ATM Forum ATM, between the user and the CO.
In the case of the ILEC version of ATM (which, by default, is called "Access ATM"), it only supports a single PVC. The reason? There are several, but primarily because you can't unbundle a single PVC. Get it? Also, Access ATM governs the cell transfer between the end user DSL Modem and the CO DSLAM, and then it dies there. On the backplane of the DSLAM it can either resurrect as ATM of another flavor and extend throughout the edge network until it hits the IP cloud, or it can be converted immediately to IP.
Forum ATM, OTOH, would allow for an end to end PVC to be set up and torn down, or allow the PVC to be extended deeper and throughout the provider's network, until it hops onto the IP cloud, or may go native ATM, end to end, over a network of their own.
In a recent article on this subject, i.e., between the differences between Forum and Access adaptations of ATM, Tom Nolle does a much more thorough job of explaining these distinctions. I believe the article was in the Dec 2000 or Jan 2001 issue of Business Communications Review (BCR).
Other providers' DSLAMs are more in line with Forum ATM and support multiple PVCs, so they can support packet voice operating side by side with data apps over the same access pipe.
An interesting side note on this topic: Yesterday, Alcatel released a version of their CO-based DSLAM which will support multiple voice sessions over ADSL, but only in countries outside of the USA. This, for the same reason I cited above. Because even their DSLAMs in the USA, due to the purchasing agreements with the ILECs, only support a single PVC.
In other countries those same nests support upwards of 8 voice channels, depending on the grade of DSL and distance from the CO. Upstream in this thread, a ways, I made comment of the recent ITU ratification of HDSL-like DSL standards, stating that this is what the ILECs have been waiting for to begin supporting professional/enterprise-oriented flavors of DSL, and other integrated services such as voice and video over DSL.
As for expert analysts, I've only read material from a handful of true experts in this space, out of the many who write about it. Sometimes they don't read the technology balance sheets as well as they read the financial ones. So when shopping for an expert analyst, the same general rule applies here as anywhere else: Buyer Beware.
Gotta run. Later.
FAC |
