VDSL - ADSL - G.hs(HandShake) - Japan xDSL - Webmaster & EDH

For the last few years, I have been involved with developing technology and standards for xDSL. xDSL provides very high speed access to the internet for homes and business. An overview article on xDSL standards: Report on Global xDSL Standards from the ITU appeared in the December 1998 issue of The Telechoice Report on xDSL.

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There are two standards for ADSL: G.dmt (G.992.1) and G.lite (G.992.2). G.dmt provides access speeds of several megabit/sec. G.lite provides access at about one megabit/sec and is consumer installable.

G.handshake (G.994.1/G.hs)

G.994.1 is the common handshaking or activation procedure for ITU-T xDSL modems. It is fully interoperable with the activation procedures for legacy DSL modems but offers several benefits for service providers: robustness, exchange of capabilities information, notification of the application and service requests, backwards and forwards compatibility for other DSL modem standards.
Higher layers on each end of the DSL modems can indicate service and application requirements during the handshake so that the appropriate DSL Recommendation from the family of DSL Recommendations will be activated following the G.994.1 handshake. This allows providers to flexibly tailor the service bandwidth and latency requirements of the customer's dynamic applications and environments including mobile DSL modems or modem pooling.

Contributions developing G.hs

Contributions developing next generation G.hs and xDSL intialization

XDSL in Japan

Japan's unique TCM-ISDN ping pong modulation can cause particularly strong cross talk interference into xDSL systems. Several Japanese companies developed the Dual Bit Map (DBM) technique that synchronizes xDSL transmission with the TCM-ISDN transmission in adjacent pairs giving xDSL in Japan the same performance as other regions. The companies received the Nikkei 1999 Technology Award for the DBM technology incorporated into Annex C of G.lite and G.dmt.

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Q4/15 Webmaster

I have promoted the use of Electronic Document Handling (EDH) in Q4/15 by designing an integrated system based on PERL scripts that: