Every time AWRE hits an even doller mark, I buy more. This Is The only Co. With Earnings, (excluding PAIR) I think theres enough room for 2 xDSL Co's. in communications. We could go down to 3 and I would buy more. No problem.
This Post is for everyone concerned: OCT 22
By Loring Wirbel
Modems and DSLs, revisited
When I wrote a Dataport Online piece last summer on the shifting standards battles in analog modems and Digital Subscriber Line (xDSL) technology, I never dreamed the entire analysis would be outdated before Halloween. But then, I never anticipated that so many OEMs and semiconductor suppliers in the modem industry would try to hype a central-office digital synchronization scheme as a "56-Kbit modem." To borrow an old line from Vietnam War days, "truth is the first casualty."
We revealed in the print edition of the October 14 edition of EE Times that the technology commonly called a 56-Kbit modem actually uses a V.34 28.8-Kbit modem chip set that is synchronized against two clock cycles of a central-office modem pool with digital termination. The higher 56-Kbit speed only is maintained in the downstream path to the home suscriber, while return-path speeds are limited to 28.8 Kbits, or in some lucky cases, 33.6 Kbits.
Within 48 hours after our edition hit the streets, U.S. Robotics was holding press conferences on East and West Coasts, to announce collaboration with Texas Instruments Inc., UUNET, and America On Line on a 56-Kbit technology called "x2". Lucent Microelectronics countered with an announcement of its V.flex 2 algorithms. And Rockwell Semiconductor Systems announced it already was shipping central-office modem modules to OEMs, which would allow a single central-office device to handle an ISDN call or an analog modem call, with 56-Kbit downstream speeds.
All the vendors tried to avoid or downplay mention of the digital termination service necessary to make this modem technology work. U.S. Robotics even claimed in its press material that the 56-Kbit service could be implemented "without the need for expensive new central office equipment required by other high-speed technologies." This statement is only true if the central office already is outfitted with digital termination and a dual-sensing modem -- something that is not true for the bulk of smaller Internet Service Providers today. And vendors involved in the 56-Kbit race were keeping very quiet about the asymmetric nature of this speed. They ought to take a lead from the Asymmetric DSL, or ADSL, vendors, who take the "it's not a bug, it's a feature" attitude when discussing asymmetric data access patterns. If faster downstream access speeds match the pattern of Internet usage, 56-Kbit players ought to be proud of the one-way nature of this technology. If they try to sweep it under the rug, home users who expect to be able to dial up other home users directly and maintain bidirectional 56-Kbit links are going to be very disappointed.
This is not to say that 56-Kbit modems are a dumb idea. In fact, market analysis firm Forward Concepts in Tempe, Ariz. expects the V.34+ modems, which use new DSP chip sets with a speed of 33.6 Kbit/sec, to have a small niche, since they do not represent that big a jump over the 28.8-Kbit speeds of V.34. The new 56-Kbit technology could have a compound annual growth rate of 71.2 percent over the next five years, the company predicts, exceeding 100 million units shipped annually by 2001.
The real potential here depends on carrier aggressiveness in rolling out HDSL and ADSL, which provide an order of magnitude faster Internet connectivity. Some regional Bells and competitive access providers are hammering on ADSL vendors to get more digital modems into trials, because DSLs are easier for carriers to provision than ISDN. Instead of the digital circuit services established in ISDN, DSLs provide a raw bit-pump service that could be ideal for Internet access.
You notice I say "could." The aggravating thing that the media itself is exacerbating can be seen in Tele.com magazine's October cover story, "Hurry Up and Wait." The working assumption is that carriers are suffering from the inability of OEMs and IC vendors to ship silicon and modem units, because the customer base is ready for ADSL now.
Come on! The real world says that the battle for line encoding, between the ANSI-approved Discrete Multi-Tone (DMT) code and the Carrierless Amplitude-Modulation/Phase Modulation (CAP) code promoted by GlobeSpan, Paradyne, and Lucent, is only going to get nastier in coming months, with no interoperability in sight.
The latest word from ANSI is that CAP proponents have struggled hard to have the coding accepted as an alternative, but several OEMs and carriers are trying to block this. But GlobeSpan, the algorithm and chip-set spinoff of AT&T, is not sitting back. It is reducing chip-set prices to less than $50 in volume, and promising CAP speeds of 8 Mbits/sec and greater in coming months. Carriers are going to be nervous about deploying a technology with two non-interoperable flavors in the market.
Besides, these are telephone companies we're talking about. Yes, xDSL is easier to provision than ISDN, and the carriers are facing new threats from CATV operators, new competitive carriers, and ISPs. But let's not expect miracles. Steve Taylor, business development manager at xDSL specialist PairGain Technologies Inc., doesn't expect widespread ADSL deployment for a few years yet, and he's more optimistic than some.
You've noticed I haven't really talked about the potential for home deployment of basic-rate ISDN. With all the frantic activity in 56-Kbit modems and xDSL, BRI is rapidly turning to toast before our eyes. But remember the "once bitten twice shy" warning. The carriers hopelessly screwed up ISDN, and they could do the same with 56-Kbit modems or DSL technologies if we aren't careful. |
