Modem speeds move higher
| Date | 01 June 1994 |
| Published date | 01 June 1994 |
| DOI | https://doi.org/10.1108/eb045328 |
| Pages | 378-381 |
| Author | Howard Falk |
| Subject Matter | Information & knowledge management,Library & information science |
Hardware Corner
Modem speeds move higher
Howard Falk
If
you
think your 9600 bit per second
(bps) modem is
fast, you
should be
aware
that
modems
operating
at 14
400
bps are now
available for under
$150,
and that vendors are beginning to
offer modems that
can operate
at 28
800
bps.
When the data
are
compressed by the
modem,
the effective
speed of transmission can
be much
higher.
For
example
if a file
that is
compressed 4
to 1 is
transmitted
by a 28 800 bps
modem,
the
effective transmission speed is an incredible
115 200
bps.
Prices for the new 28 800 bps modems are considerably
higher than for
14
400 bps units. At
the
time this article was
written, only a few 28 800 bps models were available. The
street
prices
that
can be
expected for these
modems will
prob-
ably
be
$350
to
$600.
All
these
high-speed units incorporate the operating capa-
bilities of
300,
1200,
2400
and
9600
bps
modems,
since they
downshift
to
these lower speeds automatically when a slower
modem is
at the
other end of
the
communications link.
The performance advantages of high-speed modems are
clear. Received data that appears slowly on the computer
screen at lower modem speeds will snap into place at the
higher speeds. File transfers can take place much more rap-
idly,
reducing communication
line and
database
access
costs.
There are many other needs that can be met by fast mo-
dems.
For
example,
if
you
want
to
access PCs remotely with
Windows material, or any other graphics material, modems
operating at
speeds
below
9600 bps
will
give
a painfully slow
response.
No 28
800
bps
yet for online services
For several years, online services like CompuServe and Dia-
log have been equipped to handle 9600 bps transmission.
Since
the
information
is
transmitted
more
rapidly,
fewer
min-
utes of telephone time may be used, and there can also be
savings from shorter connection time
to
the
online service.
However, based on the past performance of online serv-
ices,
adoption of
28
800 bps by these services will probably
take a year or
two.
Based on a new international standard
The main problem with 28 800 bps modems is that they can
operate
at
their
highest speed only if
the modem
at
the
receiv-
ing
end is also
capable of 28
800
bps,
and uses the same
data-
handling methods (protocol) as the sending modem. Lower
speed
modems,
regardless of
the
brand
name,
work
with
each
other because
they
conform
to
international
modem
standards
(such
as the
V.22
and
V.32
standards).
It
was
not
until the Fall
of
1994
that
the
V.34
international
standard for modems was approved, providing the basis for
universal communication at
28 800
bps.
If you buy
a modem
mat
operates above 14
400
bps,
be
sure
it conforms to this new
standard.
Please note that several types
of 28
800 bps modems
were
produced before the V.34 standard was adopted. These mo-
dems,
which use protocols described
by terms like
V.FAST or
V.FS,
are not designed to be used for communicating with
standard
V.34
modems.
Some precautions to keep in mind
Before you buy a
28 800
bps modem, there are several addi-
tional
matters you may
want
to
consider.
If you are
using
a favourite communications
program,
call
the
hotline
for
the
vendor of that software and ask whether and
when
they
expect confidently
to
operate with
the
V.34
proto-
col.
The
software vendor
may
offer
you a
free
upgrade
(or one
that comes at a price) but if you are not reassured that the
software can handle V.34, and you want to continue using
your present communications software, it might be better to
postpone moving into modem speeds above 14 400
bps.
Most fax machines
do
not
handle
incoming data
at
speeds
above
14
400 bps, so don't expect a V.34 modem to speed
your fax
transmissions.
If
you
have a
phone line
that
is
chroni-
cally noisy (sputtering, crackling, etc.) you will probably not
be able to realize any data speed increase by using a V.34
modem.
If you operate your communications through Windows,
even a recent version like Windows 3.1, the COMM.DRV
driver
may
only
be able to
handle
9600 bps
communications.
Ask
the
modem vendor
how you can obtain a
faster
version of
COMM.DRV
before
you
invest
in
a
V.34
modem.
Your
computer
may be a
bottleneck
Wim data compression and a high-speed modem,
the
rate of
data transmission can be extremely fast. While high-speed
modems are equipped to operate in
this
manner, a computer
serial
port connected
to
a
receiving modem may
not
be able to
handle data
so
rapidly without
dropping some
bits.
If you en-
counter this problem, it will show up as an increase of com-
378 The Electronic Library, Vol. 12, No. 6, December 1994
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