Overview
The same coaxial cable that delivers regular cable TV can be
used for connection to the Internet. These cables are capable of
delivering data, video, and voice signals, and the service is offered
by cable companies. A cable modem is required to access this broadband
connection. Since the bandwidth is shared among users in a neighborhood,
cable modem users my experience slower rate (less than 10 Mbps)
during the peak hours due to the heavy traffic. Data should be encrypted
before being transmitted to the users.
A cable modem is a device that allows high-speed data access from
a PC to the Internet via a cable TV (CATV) network. It is a modem
in the true sense of the word — it modulates and demodulates signals
— and it delivers Internet data to the desktop at blazing speeds.
It simply uses the increased bandwidth of the TV cable instead of
an ordinary phone line. Online access via cable modems allows PC
users to download information from online services up to 1,000 times
faster than today’s fastest telephone modems.
Here’s a quick comparison between a cable modem and a typical traditional
modem. Cable modem speeds range from 500 Kbps to 10 Mbps. A traditional
V.90/56K modem tops out at only 56,000 bits per second. That’s a
difference of 444,000 bits per second. Hardware companies are presently
developing 30 Mbps cable modems — which are thousands of times faster
than ordinary telephone modems.
For Internet access along cable lines, North America uses the Data
Over Cable Service Interface Specification (DOCSIS) and Europe uses
the Digital Audio Video Council (DAVIC) standards.
Market Research
According to Gecko Research, 600,000 users in the U.S. are currently using cable modem services. This represents a penetration of 4% of the 15 million potential customers. International Data Corporation predicts the worldwide installed base
of DSL modems from the total Internet connectivity methods to be growing rapidly from 4.3% in 2000 to 7.7% in 2002.
Market Drivers
Increasing popularity of the Internet,
- Increasing demand for high speed access to Internet,
- Rapid entrance of AT&T and other players into the cable business,
- Increasing use of cable modem services by small businesses and
SOHOs,
- Growth in telecommuting,
- Increasing availability of multimedia and interactive applications
requiring high-bandwidth capabilities,
- Cable is available to the majority of households,
- Cable modems were the first to market and have the largest customer
base,
- The increasing acceptance of DOCSIS standard,
- Increased deployment of hybrid fiber coax systems,
- Aggressive marketing of cable modem services stimulates demand
Market Inhibitors
Limited availability of cable modem services to residential
customers and businesses,
- Speed decrease due to shared nature of cable modem services,
- Relatively expensive cost of service,
- Expensive cost of equipment purchase and installation,
- Competition from ADSL services,
- Concerns over data security,
- Limited choices of Internet Service Providers (ISPs) due to
fight over open access,
- Low upstream transmission speeds discourage the usage of cable
modem services
Xilinx Solutions
Xilinx provides significant value in a cable modem when used
to interface various ASSPs together, resolving differences in their
interface control signals. The in-system programming capability
of Xilinx devices enables features to be upgraded while the product
is in the field, as well as speeding the time-to-market for the
product. The Spartan™-II FPGA or XC9500XL™ CPLD devices are ideal
candidates for this low-cost application.
As cable modems grow up into residential gateways they will support
multiple home networking interfaces. Spartan-II FPGAs provide system
integration and interconnectivity to these interfaces, hence decreasing
time-to-market, increasing time-in-market, and facilitating rapid
product proliferation in this market. Please view the presentation
to see how Xilinx solutions can help you build products for this
fast evolving market place.
|