> >>> Part 4 of 5...

Thanks for the Rockwell press releases, but please let us chew on these two
big postings for a while before any more; they're essentially advertising.

They do answer several questions people have been asking.  It's important
that people realise straight away that this is not a technology that's of
much use _except_ for connecting to centralised providers such as ISPs,
with digital links, and that it is not completely full-duplex even then
(talk of possibly achieving 30kbps in the 'upward' direction).

 > For this technology to operate, several things are required:

 >   1. The modems on both ends of the link must implement this new
 >      technology. During startup, the modems "identify"
themselves and their
 >      capabilities to each other. Only if both modems have this capability
 >      do they try to establish a 56 Kbps connection.
 >   2. The central site modem pool must have a digital connection to the
 >      network, such as with a T1 or E1 line (which may or may not be ISDN).

I guess rate of adoption of this technology here (assuming it will work
with our phone network, out of the box) will greatly depend on how ISDN
pricing moves in the next year or so.  Seems that much of Europe now has
ISDN at a price that is much more economical than using V.34 modems on POTS
links; some Europeans seem rather amused at the idea of settling for 56kbps
POTS modems.

 >   3. There must be no conversions of the digital signal within the network.
 >      Any conversions will prevent the modem DSP in the central site from
 >      generating the proper voltage levels on the analog line which will
 >      prevent this technique from operating. Examples of digital conversions
 >      are: (1) mu-law to A-law or vice versa (this means users will not be
 >      able to use this technology for communications between the US and
 >      Europe), (2) conversion to ADPCM, such as occurs in transatlantic
 >      submarine cables, (3) conversion to analog and back to digital
 >      somewhere along the link, or (4) other signal conversions such as
 >      AT&T's TrueVoice™ [9] .

That pretty well rules out BBS and general Fidonet (mailer) use of these
modems, and probably use on just about all overseas part-analogue links.

 > To check if a fully digital path exists, with no conversions, the modems
 > send a "probing" signal between themselves. If conversions
are detected,
 > the connection is established at V.34 rates.

 > These limitations are not serious, especially for Internet access which
 > generally involves a local telephone call.

Well, it's clear that ISP consumption is all they're aiming at with these. 
Not to suggest they mightn't sell truckloads of them on that basis, given
they include a V.34 modem as well, and the price is tolerable.

Whether Rockwell get this to market in time to get in ahead of the half
dozen other competing technologies being developed in the US and Europe at
the moment, many offering higher data rates over up to several kilometres
of standard copper, remains to be seen.  Interesting times ..

Ian

--- MaltEd 1.0.b5