Knowing the modem, your passport to Cyberspace

Knowing the modem, your passport to Cyberspace

By Zatni Arbi

JAKARTA (JP): Over the last year or more, hardly a single day
has passed on which I have not come across an article about the
Internet. People write and talk about the Internet everywhere, in
magazines, in newspapers, on TV and radio talk shows, in
seminars, at computer exhibitions, you name it.

Recently, the United States Information Service in Jakarta and
the American Cultural Center held a live WorldNet interview on
the Internet. Furthermore, stacks of books containing Internet
manuals and guides can be found on the shelves in computer
stores. The Internet has become perhaps the most publicized topic
in the history of mankind.

The reason I'm still hesitating to get on the Internet,
though, is the potential expense that the local telephone usage
may accrue. In addition, I don't think I can afford the time to
explore such a tempting territory, at least for the time being.
Nevertheless, a lot of people have come and asked me what they
need to get on the Net. Of course I tell them that the first
thing they need is a good modem for their PC or Mac.

In this article, I'd like to share with those of you who
haven't yet got themselves a modem some of the basic features
that they should consider in choosing one, as there are at
present literally hundreds of modem models on the market.

In countries and places where Integrated Services Digital
Network is already available, the telephone line is digital. If
your office has a digital PABX and digital internal phone system,
the telephone line that connects to the telephone set on your
desk may be digital as well. But for the rest of us, the
telephone line here in Indonesia is still analog.

The computer, on the other hand, uses digital signals. They
process and transmit data that is represented by ones and zeros.
Therefore, to connect two computers via the telephone line, we
need a pair of boxes that convert digital signals to analog and
vice versa. We call these boxes the modems -- which stands for
Modulation Demodulation. IndoInternet and RadNet, two Internet
access providers for Jakarta, have modems attached to their
computer. Thus, we also need a modem on our end of the telephone
line if we want to access Internet using their service.

There are basically two types of modems: internal and
external. The internal modem is a card that you insert into an
available slot in your PC, Mac or notebook. The good things about
internal modems are many: First, they are cheaper than external
modems. Second, they do not require a separate power supply.
Third, if your serial port doesn't have the fast 16550 UART, the
internal modem can overcome this problem easily and give you the
highest speed (more on this later).

The down sides are, first, if you happen to have more than one
PC or Mac, you cannot easily move your modem from one computer to
another, as taking out and installing internal modems would mean
opening the computer case. Second, you wouldn't be able to really
check what is going on in your on-line connection, as there is no
LED or LCD display for internal modems.

On the other hand, external modems cost more and they require
their own power supply -- usually from a power adapter. The good
things about external modems are that they are easy to move
around from one PC to another, and they also have LEDs or even an
LCD panel that tells you in plain English what is taking place.
In other words, you'll be able to see at which speed the
transmission is taking place.

One type of internal modem that is closer in convenience to
the external ones is the PCMCIA modem. As the name tells you,
this one is a PCMCIA fax/modem card that you can easily insert
into the PCMCIA slot of your notebook. It shares the
transportability of external modems, but it doesn't give you the
read-out capability of external modems. If both your desktop PC
and notebook have a PCMCIA drive, your most cost-efficient choice
is of course the PCMCIA type.

What to look for

Price is always a significant factor to consider. Modem prices
range from Rp 100,000 to Rp 2 million and beyond. As you would
naturally expect, the more expensive a modem is, the more
features it has.

Speed is one factor that distinguishes one class of modem from
another. In 1992, the standard maximum speed was 9,600 bit per
second (bps). It has jumped to 28,800 bps (28.8 kbps) this year.
Needless to say, we want to use the fastest modem that we can
buy, as it will give us better response and shorter log-in time
-- which will lead to lower bills at the end of the month.

This brings us to at least four different types of modems --
depending on which standard protocols they comply with. We have,
at the highest end of the hierarchy, the newly set V.34 class
modems, the maximum speed of which is 28.8 Kbps. Below that, we
have the V.32Terbo, which is capable of 19.2 Kbps transmission
speed. Below the V.32Terbo, we have the V.32bis modems, which are
capable of transmitting at the 14.4 Kbps rate. At the low end, we
have the V.32 modems, which can ship files across the phone lines
at the maximum speed of 9,600 bps. What do these speed ratings
translate into? If you need to transfer a 5 MB file, the V.34 can
complete the task in less than eight minutes. The V.32Terbo can
finish the job in 11.38 minutes, the V.32bis in 15.17 minutes and
the V.32 in 22.76 minutes. If you know what a pulse (two minutes)
costs, you can now calculate the amount of savings you can get by
buying a faster modem over a one year period.

Modems are backward compatible, which means that faster modems
can always work with slower ones. Keep in mind, though, that high
speed capability will mean nothing if the phone line is noisy.
Unfortunately, having a noisy phone connection is the rule rather
than the exception in Indonesia -- unless you're connected via
the Palapa satellites. Given this fact, perhaps it's overkill to
buy the fastest modem on the market today, the V.34.

Many high-end modems also use the V.Fast Class (V.FC)
protocol, which is not exactly an official standard. However,
there is a huge base of V.FC modems out there already, so, in
case you still decide to buy a high-end V.34 modem, you'd better
make sure that it also has V.FC capability.

The serial port that connects an external modem to the PC can
become a bottleneck that limits the speed of transmission. If
your PC has been around for a couple of years, chances are that
it has the older, 8259A or 16450 based serial port. This
communication port -- usually called COM port, for short -- only
has a one bit buffer. Therefore, it can easily lead to data
overrun. For higher speeds, you will need the new 16550 Universal
Asynchronous Receive and Transmit. You can check your PC to see
which UART it has by running Microsoft Diagnostics utility (type
in MSD at the C: prompt and hit ENTER). If the utility tells you
that it still has the old 8520A or 16450, your best solution is
to buy a new I/O card with the 16550 chip. If your motherboard
has a built in COM port -- and most current motherboards do --
you will have to disable it -- usually by changing dip switches
or CMOS settings.

Internet is not the only reason why you should also consider
adding a modem to your system. In the era where telework is an
option we should seriously consider, a modem is like the car that
you use to commute. In addition, almost all current modems have
faxing capabilities, so that you can fax documents directly from
your desktop PC or notebook. In other word, you no longer have to
print your document, go to your stand-alone fax machines, dial
the number of your recipient, and feed the printed pages.

The way the PC-based fax works is like this: You print your
document into the fax driver instead of into the printer. This
will then invoke the fax utility, and you type in the recipient's
fax number, and a click on the OK button will send the fax across
the telephone network -- possibly to the other end of the globe.

Given the quality of the telephone lines in Indonesia, I guess
we can safely say that we don't need the V.34 modem just yet. The
V.32 is adequate for most purposes, until PT Telkom successfully
improves our public telephone networks.

However, one excellent feature of the V.34 modem is that, when
connected to another V.34 modem, it will always conduct line
probing and adjust transmission speed dynamically. This may make
it worth the extra cost.

By the way, I've also seen at least one model of fax, AcerFax
F-26, which has a built-in modem capability. It's a neat
peripheral for your PC, if your requirements are not heavy.
AcerFax F-26 can function as a scanner, a copier, and a stand-
alone fax machine in addition to being a modem, and the price is
very reasonable.

The next time around, we will have a look at a very expensive
fax/modem from Hayes, the pioneer in modem technology, to see
what other features to consider when buying a new high-end modem.