[hdsl2]
hi SoMo,
many thanks for the report from the telecom israel exhibition..
seems like silicon news is creeping up on us.. adsl/g.lite for jan.. vdsl prototyping... and expect hdsl2 with rok as well in the not too distant future...
altho vdsl is flashier, expect that hdsl2 has more potential nearterm.. as i understand it, the hdsl market in the usa is an established one and new players such as orctf are counting on hdsl2 to shake things up... hdsl/sonet integration could be a big deal.. and hdsl2 purportedly could open that door for orctf/fujitsu.. hdsl2 very likely will replace hdsl1.. hdsl2 supposedly will be much lower in cost and will be a more advanced technology that serves the same applications... and also could open up some new angles such as "interactive multimedia, and home- and business-based web servers...."... time will, of course, tell for both hdsl2, orctf/rok silicon and orctf's hdsl2 strategy..
and on the silicon side, would think we should be hearing something from orctf/rok in the relatively near future as the competition (level 1/pair hdsl2 cooperative effort) has been making noises recently.. and the last announced timeframe for orctf/rok was roughly the same (late 98 early 99)..
and hdsl2 standards, apparently, are falling into place:
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ITU actions push ADSL, HDSL forward
By Loring Wirbel
EE Times
(10/28/98, 1:58 p.m. EDT)
GENEVA — Two weeks of hard work in mid-October have led to a full determination of international standards for asymmetric digital-subscriber-line service, and to a final approval for high-bit-rate DSL and a task-group assignment for HDSL-2. The International Telecommunications Union's telecommunications group (ITU-T) approved the splitterless, "G.lite" ADSL as G.992.2, augmenting the G.992.1, or G.dmt, standard for full-rate ADSL.
ITU's whirlwind of approval mechanisms set off a round of supportive statements by semiconductor companies working on ADSL. Rockwell Semiconductor Systems, Centillium Technology Inc., Lucent Microelectronics, Texas Instruments Inc., Motorola Inc., Integrated Telecom Express Inc. and others have expressed full support for both full-rate ADSL and splitterless ADSL.
Ken Krechmer, editor of the Communication Standards Review, told a U.S. videoconference audience at the recent DSLcon that the related DSL standards, dealing with handshakes, test procedures and physical-layer management, are as important to ADSL as the much-discussed G.lite and G.dmt. The handshake procedure, approved as G.994.1, uses a startup procedure for DSL modems similar to the V.8/V.8bis methods used in high-speed analog modems. Les Brown of Motorola Inc., editor of the standard, said G.994.1 is specified for ADSL but will likely be adopted for HDSL/HDSL-2 and very high-bit-rate DSL as well.
The G.996.1 test procedures standardize the means of testing modem performance and assuring interoperability. The specified methods are similar to the V.56bis/ter procedures for analog modems.
G.997.1 physical-layer management sets up operations, administration, maintenance and provisioning procedures, based in part on the Simple Network Management Protocol.The American National Standards Institute (ANSI) T1E1.4 working group for HDSL-2 will decide on those procedures at a December meeting and may adopt G.997.1 as the basis of its work.
Finally, G.995.1 is an overview of all DSL recommendations within ITU-T. It includes a system reference model.
While ITU-T's blessing can't be expected directly to jump-start deployment of ADSL among carriers in North America, a spokesman for Compaq Computer Corp. said that, "at the very least, this assures that one product will have a worldwide market based on global standards."
Meanwhile, supporters of HDSL-2 expect to finish ANSI-specific span-power and operations, administration, maintenance and provisioning specs in December and to bring a nearly completed draft to ITU-T in January. HDSL-2 allows symmetrical T1 (1.5-Mbit/second) services to run over a single copper pair to distances of 12,000 feet.
Sean Martin, vice president of marketing at ADC Telecommunications Inc., said a milestone for HDSL-2 hardware rollout was reached in September with the completion of physical-medium-dependent standards. The work allowed Level One Communications Inc. (Sacramento, Calif.) to provide mixed-signal chip sets to early customers.
ADC has tested Level One's first silicon for HDSL-2 and is convinced that products incorporating the standard can be released in the first quarter. Level One also is supplying PairGain Technologies Inc. (Tustin, Calif.) with chip sets for imminent release of HDSL-2 concentrators.
At present, multi-pair HDSL is handled under G.991.1, and HDSL-2 is designated G.991.2. Mike Rude, lead editor for the HDSL-2 standard and a technical marketing manager at ADC, cautioned that there might be slightly more work in resolving ANSI and ITU standards for HDSL-2 than had been the case for ADSL.
That's because the HDSL-2 group decided to split the standards effort in half for North America, developing a T1-only option on a fast track and adding support for additional speeds later. ITU-T, by contrast, wants to place all speeds of HDSL-2 under a unified G.991.2.
Nevertheless, Rude said, the degree to which global standards bodies are working together on all xDSL standards is encouraging.
eet.com:80/story/OEG19981028S0010
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thanks again
s
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