>Date: Wed, 9 Sep 1998 17:01:40 -0400
>From: "Victor L. Boersma" <[email protected]>

>Live and learn.  I thought that the Japanese were the same as North America
>all the way, BUT NO, at the DS-3 level they become deviant.

>  DS-3        32.064 Mbps   480 voice channels

I wonder if that is actually used in Japan?  The JATE "Green Book" Form
U-III only mentions "Leased circuit (Super-high speed code) : 45, 50, 150
Mb/s," and all of those are optical, not on copper.

I've tested DS-1 and DS-2 for Japan, and their DS-1 is now identical to
North America.  (They used to use CMI, but about nine years ago they
started switching over to the technically-inferior AMI to be completely
compatible with North America!)  DS-2 never caught on in North America, but
apparently NTT invested heavily in it in Japan.  There is a difference,
though.  North American DS-2 uses B3ZS, and Japanese DS-2 uses B8ZS.


________________________________________________________________
 John Combs, Senior Project Engineer, ITS/TestMark Laboratories
 Email: [email protected]          URL: http://www.testmark.com

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