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the times has the following article on connections.......if part is
missing.......nytimes.com
Plugging In to the Internet: Many Paths, Many Speeds
By PETER WAYNER
The first thing anyone who wants to connect to the Internet has to
realize is that the Net is not a
single entity - it is a collection of networks joined by a set of
standard ways to exchange data.
The name Internet even implies that it links networks. This means that
almost any system for carrying data -- wires, radio, fiber optics or even
smoke signals -- can be hooked into the Internet if it can send that data
in
the format known as the Internet Protocol, or I.P.
The good (or bad) news about this open standard for a network is that
there are many options for getting connected to the Web. The most popular
way is to use the telephone, but new options using the cable system or the
cellular phone system are expanding rapidly.
Of course, not all choices are available in all areas. Some of the
fanciest systems are just being
introduced in tests around the country. Others are offered by companies
that serve only small
regions. With the array of choices available, it is difficult to give
straightforward advice that applies to
most people.
Still, there is one general rule: Faster is better. That sounds like a
simple
standard to apply, but it's surprisingly complex. Some systems can provide
great speed consistently. Others offer it only in bursts. Some require you
to
share the road with your neighbors, which means that service will be
slower
when people are home and faster when everyone else is asleep. On others,
information moves at different speeds when it travels in different
directions.
You might be able to download, or receive, large volumes of data quickly,
but the time to upload, or send, information could be much slower.
The problem becomes even more complicated because a fast connection
between you and your service provider does not guarantee that information
will arrive quickly. Data will often travel through more than 20
connections
between your machine and a distant Web site. The weakest link limits the
speed at which your computer will get the data.
Another important detail is service. Some people are comfortable working
with computers, while
others want someone else to worry about the details. Some of the biggest
brands in the on-line
business got there by concentrating on making their connecting process as
simple and bulletproof as
possible.
Ways of connecting require not only special hardware and software but also
a relationship with an
Internet service provider, known as an ISP Look before you leap, and add
up all the costs and
benefits. This is only a general guide; specifics vary considerably from
place to place and from
company to company.
So, with that said, here's a thumbnail guide to the sometimes bewildering
world of connecting to the
Internet.
Ways to Connect
PHONE LINE (ANALOG)
Maximum speed*: 56 Kbps.
Download time for "Moby Dick" online book**: 2.8 minutes at 56 Kbps.
Cost: $30-$200 for modem, ISP charges extra.
Availability: nationwide.
hile the telephone system is the most common way for people to
connect to the Internet
from home, it was engineered to carry voices, not data, over the
lines. Modems to carry
data were developed as afterthoughts, and the phone companies are fond of
saying that they do not
guarantee that modems will work. Many glitches people report with modems,
like sudden
disconnections, are in some ways the result of trying to carry data by
turning it into high-pitched
squeaks through a modem.
Despite that, connecting with the phone system is relatively easy, and
phone service is almost
ubiquitous. Most ISP's offer CD-ROM's or floppy disks with all the
necessary software to connect
through a modem. These are usually programmed with the standard settings
for most major
computers and modems, but problems still occur occasionally. The ISP's
also offer some
hand-holding advice if things go wrong.
One of the biggest headaches for some ISP's is providing enough phone
lines. They get charged for
each line coming in to their headquarters, so they try to minimize the
number of lines. Also, growth
can swamp an ISP. (Remember when America Online gained so many customers
so fast that many
had problems connecting?) Companies are still trying to find the right
balance of prices and service
for a sustainable ISP business.
A recent problem has arisen from the slightly confusing transition to 56 K
modems. They are
supposed to move data at the rate of 56,000 bits (or 56 kilobits) per
second, roughly equivalent,
depending on the technology, to 1,000 to 2,000 words per second. Often
phone systems cannot
support high speeds, and these modems are forced to work a little more
slowly. Two companies
tried to corner the market in the modem business by introducing competing
standards that could not
interact. A compromise standard, called V.90, has been designed, but it is
not widely available,
which means that your modem may not communicate well with your ISP's
modem, and the glitches
can be maddening because they can seem random.
ISDN
Maximum speed*: 128 Kbps.
"Moby Dick" download time**: 1.2 minutes.
Cost: $0-$250 for installation***, $30-$200 per month for service, ISP
charges extra.
Availability: most major cities.
ADSL
Maximum speed*: 1.5 Mbps-8 Mbps download, 640 Kbps upload.
"Moby Dick" download time**: less than a second.
Cost: $300 and up for installation, $60-$400 per month for service, ISP
charges extra.
Availability: limited mostly to trial areas in major cities, including New
York.
aster digital telephone lines are available from phone companies in
some parts of the country.
The services are called ISDN, for integrated services digital
network, and ADSL, for
asymmetric digital subscriber line.
ISDN is older and slower (up to about 128 kilobits per second) than ADSL,
but it is available in
more areas of the country.
ISDN, the first major attempt by the phone companies to move toward a
digital system, allows
people with the service to get both voice and data calls on the same line.
That is why the system is
called integrated.
ADSL is much faster, but it is available only to lucky people living in
the right neighborhoods.
Phone companies are experimenting with many different variations of
digital subscriber lines and
tagging them with similar names. For this reason, some people use the term
xDSL to refer to the
entire batch; the ''x'' stands for any of the possible acronyms.
The prices for these services can be confusing because each phone company
has persuaded the tariff
board regulating it to allow different rates. As a result, the cost of
ISDN can be reasonable in some
parts of the country ($40 per month), but a luxury ($200 per month or
more) in others.
A bigger problem is the lack of widespread expertise with the technology.
You have to buy a
different type of modem to use either ADSL or ISDN You might also need a
new phone line or two.
People are usually happy with the fast connections -- once they get them
working. In many cases,
the local phone company will sell a package that includes installation,
but the amount of support
varies. And you will still need an ISP in addition to your phone line.
That makes the hardware and
service pretty pricey, but some people think that it's worth it.
CABLE MODEM
Maximum speed*: 1 Mbps-10 Mbps download, 768 Kbps upload.
"Moby Dick" download time**: Less than a second.
Cost: $0-$300 for installation***, $40-$50 per month for service above
television bill, includes ISP
Availability: limited to major metropolitan areas.
he cable television companies realized long ago that their shielded
wires, which are protected
against electromagnetic interference, could carry much more
information than the largely
unshielded wires used by the telephone company. The downside is that many
homes in the same
neighborhood, known as the local loop, share the same cable wire, much
like a telephone party line
in the past. The first adopters of cable-modem Internet links speak
lovingly of their high-speed
connections, but it is unclear whether performance will suffer in the long
term if everyone in the
neighborhood starts downloading big files at the same time. No one knows
how usage patterns and
service commitments from the cable companies will evolve over time.
Right now, cable access to the Internet requires a special modem that is
usually installed by a
technician from the cable company. The technician will also check your
system to insure that the
proper security provisions are in place. That is important because the
party-line nature of the
technology makes it easier for neighbors to poke into your business.
Access to cable-modem service is limited by economics. The cable companies
are rolling out new
service in some areas, like Baltimore County and parts of New Jersey, as a
test. Each company
decides where to offer service based on how much money it thinks it can
make in an area, so it helps
to live in a place filled with other Internet addicts. Comcast, the cable
company serving Baltimore
County, is spending heavily to offer the service in that suburban area,
while the company serving the
city of Baltimore, TCI, has been taking its time.
T-1 LINE
Maximum speed*: 1.54 Mbps.
"Moby Dick" download time**: 0.105 seconds.
Cost: $1,000 and up for installation, $500-$1,000 or more per month for
service, ISP charges extra.
Availability: Anywhere a dedicated line can be installed.
usinesses with local networks often get on the Internet by leasing
from the phone company
high-speed lines that link directly to major ISP's. All the traffic
from an office network is then
shipped out on one of these high-speed lines. It is much more reliable and
efficient than putting a
modem on each desk.
These leased lines, which include T-1 lines, come in a variety of sizes,
and the price often depends
on the distance to the local switching center. It is hard to generalize
about these prices, but
lower-capacity lines often run between $300 and $1,000 a month just for
the telephone company's
fees; T-1's can cost $1,000 to $2,000 a month or more. There are
additional costs from the ISP that
handles the job of shipping the data to the world.
The idea of sharing leased lines is becoming popular in apartment
complexes. Sometimes a group of
neighbors will form a cooperative to share the costs. In other cases, a
real-estate developer will
provide the service as an incentive for home-based businesses and other
small companies that
cannot afford their own technology staff. And many luxury apartment
buildings are starting to offer
such lines to attract tenants.
Less-Traveled Roads to Cyberspace
SATELLITE HYBRIDS
Some of the same companies that make the digital satellite dishes used for
television reception are offering Internet service through the same
system. The
good news is that the bandwidth from the satellite to your house is high.
The Web
pages you request travel down a channel that can easily handle 500
kilobits per
second or more.
There are two caveats: First, the channel is a party line shared by all
users in the country and,
second, the bandwidth out of your house is more conventional because it
travels over phone lines
using a modem. If your Internet usage involves lots of short requests for
big blocks of data, then the
imbalance is not a problem. But if you want to ship out as much data as
you pull in, this service is not
the best solution. Digital satellite systems like Hughes's DirecPC are
available at most places in
North America where you can hang an 18-inch satellite dish and point it
south.
CELLULAR-BASED WIRELESS SERVICE
Many cellular phone companies are offering wireless Internet service,
which is
integrated with the system that provides cellular calls. The Internet
service requires
a special type of modem with an antenna. The quality of the service, of
course,
depends upon how well radio signals travel in your neighborhood. Tall
buildings can be a problem,
and signals will sometimes not penetrate deeply inside other buildings.
The quality of the service can
also depend on the distance between the modem's antenna and the nearest
cellular system antenna.
The radio modem often works well with laptops. That kind of tetherless
freedom is its biggest selling
point.
The cellular companies are adding new data-carrying service throughout the
country, but coverage
varies widely and you should check with your local carrier.
OTHER RADIO-BASED SERVICE
A wide variety of radio modems are offered by companies that do not sell
phone
service over their networks. These are often used by businesses like
package-delivery companies and cab companies to keep track of their fleets
and
dispatch them. Still, some offer service that can be used by the average
consumer.
The structure of these networks varies. In some cases, there are thousands
of
small antennas attached to lampposts throughout the city. Metricom is one
example of a company
using this solution, but it does that in only three major metropolitan
areas -- the San Francisco Bay
area, Seattle and Washington. In other cases, companies use satellites to
broadcast information to
reach all of North America. That is popular with trucking companies. Other
wireless companies use
methods similar to those used by the cellular phone industry, with towers
every mile or two.
BROADCAST SERVICE
One of the more intriguing ways to get information from the Web is just
emerging.
Some companies are sending information hidden in the corners of radio and
television signals. Users with television cards in their PC's can program
their
computers to grab this information and store it locally.
These methods are great if you want access to sophisticated and popular
information without
waiting. It may take too long to download a film clip through a modem, but
a news company could
broadcast the same clip to people throughout the country simultaneously.
The next time you turned
to your machine, the entire clip could be stored on your hard disk.
But this approach has several limitations. You can get only what the
broadcaster wants to send you,
so only the major services with broad appeal, like CNN.com, will arrive
this way. Also, you cannot
send data through your card. Most people will want to maintain a standard
dial-up service to handle
E-mail and Web data that the broadcasters do not offer. Still, if you
regularly check the weather,
headlines, sports news or other popular services, broadcast service has
plenty of appeal.
LOW-EARTH-ORBIT SATELLITES
Among the most interesting systems on the drawing boards or operating
today are
the constellations of satellites in low Earth orbit. These fly only 500 to
1,000 miles
above Earth to minimize the time a radio signal spends in transit. A large
number
of satellites (66 in one system and 288 in another) are needed to insure
that one
satellite is always overhead.
Some of these systems are already well along, but getting one in operation
isn't easy. The companies
that want to offer satellite service must negotiate licenses for radio
frequencies from many
governments and deal with local service problems. Also, leaves and trees
block some of the signal
from the antennas on the fast-moving satellites and on the ground. And
simply launching 288
satellites is no small feat.
Still, these satellite systems promise to change the equation around the
globe. If they are successful, it
will suddenly be easy to get the same level of service in Kansas, the
African veld or Silicon Valley,
and that could have significant political effects.
* Represents highest speed at which data can be transmitted in ideal
conditions. Often lower in actual use.
** "Moby Dick" download time based on 1192K version of the novel at Books
Online.
*** Cable modem and ISDN equipment may be free in promotional areas.
Peter Wayner at pwayner@xxxxxxxxxxx welcomes your comments and
suggestions.
Timothy Morge wrote:
> Yuri:
>
> First, it is reliable, but remember, in most cases, you are simply using a phone
> line to access the downlink of THEIR satellite dish. That's certainly the case
> with FS...I don't know the origin of the Comstock data. The exceptions would be
> a 'raw' Reuters feed or something similar.
>
> I have had fiber optic connections, T1 and T3's, satellites and dial-ups and
> even FM reception. I find my satellite dish very reliable.
>
> Tim Morge
>
> Yuri K wrote:
> >
> > Does anyone have any experience with dedicated phone line datafeed?
> > This is my only option in the area with FS or Comstock.
> >
> > Salespeople promote it as "the most reliable", but there are also so called
> > "dial-up back up" options on their price lists.
> >
> > Then, it's expensive to install.
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