To Purebull and all PAIR followers:
Given the negativity that has resulted from the US West announcement about dropping PAIR in favor of a "splitterless" ADSL solution, I thought the following article from last week's PC Week might be of interest to the thread. The article makes a clear point that it will be a while before "splitterless" ADSL becomes a threat to conventional ADSL. Thanks to all the thread regulars for the great information shared on this thread.
Perhaps this article was already posted last week, but if not, here it is:
PC Week: January 19, 1998, Page 89
HEADLINE: PC Week Labs examines the means to cheaper deployment of ADSL.
By incorporating more intelligence into end-user devices, hardware vendors are trying to reduce the costs of deploying high-speed ADSL data lines.
In early trials, installation of ADSL subscriber lines has required telephone company service personnel to also install a unit known as a splitter, which cleanly separates the data and voice signals coming over the copper wire. The relatively high cost of installing ADSL, which ranges from $300 to $450 (the cost of the ADSL modem can be several hundred dollars extra), has contributed to making the fledgling technology unattractive to consumers.
"Splitterless" ADSL hardware designs are emerging that will eliminate any need for specialized installations. In essence, companies such as NetSpeed, Inc. and Rockwell International Corp. are putting a higher degree of distortion tolerance into ADSL modems, so they do not require the clarification of the data signals provided by a splitter.
However, PC Week Labs' analysis of early specifications for the technology indicated that it will be a while before splitterless ADSL products become available to-let alone popular with-the general public.
Most splitterless ADSL development efforts are focusing on lower-power devices in the 1 to 1.5 watt rage instead of the 5 to 8 watt range of traditional ADSL. The lower power reduces the interference on low-quality household phone wiring, but it also necessitates a corresponding drop in data transmission rates.
Lightweight splitterless ADSL modems run at a maximum of 1M-bps upstream throughput versus the 8 M-bps possible with standard ADSL. The lower speed might handicap lightweight ADSL's popularlity. Although the modems will be many times faster than even the speediest 56K bps analog modems and will likely be sufficient for most users, splitterless devices won't live up to all the ADSL hype.
In addition, there are currently no standards for splitterless ADSL devices, although the ITU is working on a specification called G.lite. The advent of G.lite would not mean that faster conventional ADSL solutions are doomed to obsolescence. For business, 8M-bps ADSL could still be a cost-effective alternative to T-1 lines, because it offers faster performance.
Lack of standards hasn't stopped some vendors, including NetSpeed and Northern Telecom Ltd., from shipping low-power ADSL modems to telephone companies for tests. Higher speed ADSL might be relatively expensive to install compared with analog phone lines, but it is highly competitive with frame relay and T-1 formats.
Efforts are also underway to utilize splitterless technology without the tradeoffs of lower power and lower throughput. For example, high-speed 8M-bps splitterless ADSL modems are available from companies such as NetSpeed.
Even here, however, the compromise could turn out to be one of price. The price for lightweight ADSL hasn't been finalized, but it promises to be considerably less expensive than its conventional ADSL sibling.
Best of luck to all of you.
JMaz |
