A response to inaccuracies of a previous post.

>56K is the result of data compression technology, not actual transmission
>speed.

56k is NOT the result of data compression technology, it is the result of
taking advantage of the digital nature of phone lines, at least from the
phone company central office to the modem you are connecting to, and
requires that the other end have a digital phone company connection, such
as via ISDN, T-1, etc.  When you add compression, it's possible to reach
speeds of up to around 5 times the throughput of the raw speed of the modem
with a highly compressable file, but with a basically uncompressable file,
such as a zip file set to maximum compression, it is possible to get up to
around 2 kilobytes per second in additional speed when downloading a file.
One restriction of 56k modem technology is that it can only survive ONE
Analog/Digital conversion, and if a second conversion takes place, the
connection is not possible at 56k speeds.

>Point 2.
>The USR "line test" merely attempts to negotiate a connection at the highest
>possible speed AND compression technology.  .  The line quality is only one
>half of the equation.  The other half of the equation is the data
>compression algorythm.  If the two modems are not using compatible
>algorythms, then 56K will not be acheived.

This is NOT what the USR line test tests, it tests to see if the the
connection between the test modems on USR's end and your phone company
central office is entirely digital or not.  It may have taken a different
route with the new modem, which would cause the difference in the test
results, and therefore may not always be accurate, but it does NOT test
compression technology at all, nor does it care about the speed it acheives.

>Point 3.
>When a phone call is made, the telephone (modem) dials a number and connects
>to the Telephone Company's  (TelCo) switching center, which then makes a
>connection to one or more switching center OR to the dialed number.  When a
>modem "calls" the local ISP, or calls the USR line test, the first part of
>the connection path (from the modem to the switching center) remains
>constant, but from the switch center outward, there are very different
>circuits.  USR is testing (and I use that term VERY loosely) the connection
>from the dialing modem to the switch center.  It can not "test" the circuits
>from the switch center to the ISP.  Therefore it is only a partial test.

The line test does NOT test your lines, which doesn't matter as much as the
connection from your local Central Office to the end modems, in this case
at USR.  It can't test the lines to your ISP, only to their modems.

Matthew Ballard
Computer Consultant

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