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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Coincidence...
> > At 02:48 PM 07-05-97 -0700, Michael Dillon wrote: > > > >I though that ATM cell sizes were so small in order to better support > >real-time voice and video. > > The original ATM compromise was designed to avoid screwing up echo > cancellation on the last mile loops which is very sensitive to delay and > hard to adjust since it is old fashioned analog hardware and not digital. > That is one of the more difficult aspects of the new xDSL technology is > dealing with echo cancellation and crosstalk in those crummy old two-wire > circuits. > Part of the story. US, Japanese and European telco manufacturers had different perceptions of 'optimal' atm cell size. Depending upon the mix voice/video/data different results were obtained; believe 32 and 64 byte were mentioned. The powers that be decided upon a compromise and chose a value 'in the middle' causing everyone to redesign their equipment. The compromise value was not a power of two. Must have been '89 or thereabouts. regards, Koen ======= ___ === Koen De Vleeschauwer, Network Engineer, ====== / / / ___ ____ _/_ ==== EUnet Communications Services BV ===== /--- / / / / /___/ / ===== Singel 540, 1017 AZ Amsterdam, NL ==== /___ /___/ / / /___ /_ ====== Tel. +31 20 5305333; Fax. +31 20 6224657 === ======= [ 24hr emergency number +31 20 4210865 ] - - - - - - - - - - - - - - - - -
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