Cable Modem: New media to surf Internet world
Cable Modem: New media to surf Internet world
Perhaps the cable network is not well known in Indonesia, but
a cable network with a background from CATV network is very
popular in the United States and Europe to deliver high speed
Internet access with cable modem. This media will give convenient
and speed of access directly to your PC at your home. Compared
with other technology to access the Internet, the cable modem is
much faster, more than 100 times the ordinary conventional modem.
Usually it is a flat rate service, depending on the bandwidth you
like to buy.
Comparing the current ways consumers can connect to the
Internet from their home, cable access comes out a clear winner.
At roughly the same cost of dial-up access with a dedicated
telephone line, and cheaper than ISDN or ADSL connections, cable
modem connections are by far the fastest, and will have those
Websites on your computer screen in the blink of an eye.
If you have a dedicated modem line and one of the latest
modems, you are probably paying between Rp 95,000 and Rp 162,000
per month for dial-up Internet access at speeds up to 56kbps
(phone line plus ISP). If you are using ISDN, you can expect to
pay between Rp 300,000 and Rp 500,000 per month for speeds up to
128kbps, and ADSL users will pay a similar amount for speeds up
to 384kbps. But if you can get Internet access from your cable
company, expect to pay around Rp 300,000 per month for unlimited,
"always connected" access at speeds up to 10Mbps (that's
10,000kbps!).
Cable Modem: What is it?
A cable modem is a device that connects to your existing cable
feed and to an Ethernet network card in your PC (also called a
"NIC" for Network Interface Card). A cable modem is a true modem
-- MO for modulates and DEM for demodulates -- but it is a much
different device than common dial-up modems.
A dial-up modem may be an internal or external device, and
connects to a serial port on your computer at a maximum speed of
56kbps. Today's cable modems are external devices that connect to
a network card in your computer, and support much higher speeds
than dial-up devices.
At this time the cable modem you need to use is determined by
your cable company. There are many manufacturers making cable
modems, although Motorola has the largest market share.
Initially, there were no standards and the different cable modems
could not talk to each other.
Recently the industry has come together and agreed on the Data
Over Cable Service Interface Specification (DOCSIS) standard.
This will allow third-party vendors to make compliant cable
modems, and should result in lower equipment costs. The first
batch of DOCSIS certified modems are due out late this year. In
all cases, the other end of the cable modem connects to an
Ethernet network card in your computer.
The cable TV network and the coaxial cable that brings it into
your house are capable of very high data transmission rates. Some
cable networks claim speeds up to 36Mbps, but the practical top
speed a modern PC with an Ethernet card can support is 10Mbps.
The cable network is designed to support the highest speeds in
the "downstream" direction, which is from the Internet to your
computer. This downstream speed affects the performance of
downloading Web pages and software. The "upstream" bandwidth --
the data sent from your computer to the Internet (mainly mouse
clicks and e-mail messages) -- is typically less, in the range of
200kbps to 2Mbps. Error! Not a valid filename.
You want it, connect it
At this time, it's rather hard to get the cable network
subscription, because it's not so popular for the CATV network in
Indonesia. The first thing if you wish to obtain the Cable Modem
line is to have the CATV network that already been upgraded to
deliver two-way interactive services.
Besides the upgrade activity, the condition of the network
itself usually has problem, because of the wrong design, or
subscriber noise that affects the network so it cannot fully
deliver the high speed Internet access.
When they are already built, the cable network, besides for
delivering high-speed Internet access it also can deliver CATV
services, Pay per View or Pay per Channels, Home Shopping, Home
Banking and Telecommuting for home office.
So, maybe next year in Indonesia if the cable network is
already built, it can fulfill the hunger of high speed Internet
access to surfers directly in their home.
Getting connected
Most modern home computers can be equipped to use a cable
modem. Cable modems connect differently to your computer than
standard dial-up modems, though, and an additional network card
is required. This is usually provided by the cable companies who
offer Internet access. Your computer must have an available slot
for the Ethernet card.
The basic requirements for a system to work with today's cable
modems are either a PC with at least a 66 Mhz 486 processor or a
Macintosh with at least a 68040 processor, and 16 Mb of memory.
Of course, performance will improve with faster processors and
more RAM on either platform. The Road Runner service recommends
32 Mb of RAM and a 166 Mhz Pentium or 250 Mhz PowerMac.
Getting started with cable modem Internet access is quite a
bit different than with a regular dial-up ISP. In most cases,
when you subscribe to Internet access from a cable provider they
send a technician to install the cable modem and verify the
quality of your cable.
The cable technician will install a splitter onto your
existing cable, which allows you to connect to the Internet while
still using this wire for your cable TV access as well. There is
no problem using the Internet connection and watching cable TV at
the same time. A cable modem will be installed on the coax cable
at an outlet near your computer.
The cable company will also arrange for the installation of
the network card in your PC, if it does not already have one. You
may be asked to take your computer to a repair shop authorized by
your cable company to do this installation, or you may even
decide to do it yourself if you are comfortable opening up your
computer and installing a card.
Whatever the specific arrangements your cable company makes
with you, rest assured they will be much more involved in setting
up your connection than a standard dial-up Internet service
provider. Gone are the days of getting sent some software you are
expected to install, or given cryptic configuration information
over the phone you need to enter into your computer. Instead, the
cable company will visit your house and install your modem, check
your wiring and arrange for a technician to install your network
card and configure your software.
Potential Downsides
While the speeds and costs associated with cable modem access
seem almost too good to be true, like any technology there are
potential downsides. With the cable TV network your computer is
essentially being put on a Local Area Network (LAN) with other
users in your neighborhood, and this presents a couple of
possible problems.
Like any LAN, the performance degrades as usage increases.
It's a fact that other users on your street, and probably beyond,
share the same data "pipe" you are using, so if everyone is
downloading at the same time and your performance will suffer.
But the cable networks offer downstream speeds greater than any
other option, even under worst case scenarios of high
neighborhood usage. It is a concern though that as this type of
access grows in popularity the cable companies may not be able to
maintain the same speed and level of service they can now
provide.
Perhaps a more disturbing issue is that of network security.
One of the main purposes of a LAN is to allow file sharing among
the computers on the LAN. This LAN feature does not work well
with cable Internet access, however, as you probably do not want
your neighbors accessing your files.
There have been widely reported incidents of this type of
breach, where a cable modem user can access files on another
user's computer in his neighborhood who inadvertently had their
file-sharing settings turned on. It's a very good idea to make
sure you do not have file-sharing allowed on your computer if you
are going to get cable modem access. Here's how to disable file
sharing.
To disable file sharing on PCs running Windows 95, go to the
Network Control Panel and click on the Configuration tab. Click
on "File and Print Sharing" in the lower part of the window, and
make sure the button by "I want to be able to give others access
to my files" is not selected. Click "OK" twice and your files
will not be visible to anyone else who happens to be on the same
LAN as you.
To disable file sharing on a Macintosh, go to the Sharing
Setup Control Panel and look for the File Sharing section. If you
see "File Sharing is Off" and a button marked "Start", you are
fine and your files cannot be accessed. If, however, you see a
button marked "Stop" you should click on it, and you will then be
prompted for how many minutes the computer should wait until it
turns file sharing off. Pick a number and click "OK" and now your
files will no longer be accessible.
Where it's going
High growth is expected in this industry from all corners,
especially in the next several years. Strategies Group Inc.
estimates that cable modem sales will grow from approximately
100,000 in 1997 to 2.7 million in 2000. Comparatively, 11 million
56k dial-up modems were sold last year. Service revenues for
cable companies from Internet access is projected to increase
from $72 million in 1997 to over $2.1 billion by 2000.
In addition to allowing for smoother Web surfing, cable
modem's high speeds and constant connection are facilitating
other new interactive applications that could not exist in dial-
up settings. Just think, the near future may offer video e-mail
and subscriptions to CD-ROM libraries. These libraries will offer
the same level of interactivity as if the CD-ROM were being
played on your local computer.
The bottom line is that today cable modems provide higher
access speed at lower prices than any other method of connecting
to the Internet. While availability is still rather limited, this
is changing rapidly. You can expect the Internet to come to a
cable TV system near you very soon.
Online Resources
Here are links to some of the major service providers and lots
more cable modem information: Road Runner Service -- www.rr.com;
TCI Online -- www.tci.com; Motorola CableComm Products --
www.mot.com/MIMS/Multimedia/; Cable Modem Info Center --
cabledatacomnews.com/cmic.htm; CATV CyberLab -- www.catv.org;
Cable Modem Resources on the Web -- rpcp.mit.edu/~gingold/cable/.
Henri Setiawan W. has worked as a fiber access network
engineer in RisTI Division of PT Telkom Indonesia since 1996.
RisTI Division is the support division of PT Telkom which
conducts R&D activity. He has been responsbile foor access to HFC
technology since 1997, written some technical specification
documents for HFC and several guidelines related to building the
HFC network.