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Converging telecom demands fuel broadband networking
By Lili Goleniewski
Advances in telecommunications have been nothing short of fantastic --
in less than ten years we have gone from discussions of integrating
voice, data and video communications to visions of networks capable of
transporting the full range of human senses. In just the last five
years, the level of data traffic has grown to equal that of voice, and
video communications has been consistently demonstrating growth rates of
50% per year.
And even then we are only at the beginning of a new era of
communications -- one characterized by convergence -- the convergence of
networks (witness the @Home topology), the convergence of devices (like
Microsoft1s WebTV or Philips P200 Internet Home Phone), the convergence
of applications (the edutainment value of DK encyclopedias), and
ultimately, the convergence of man and machine. The next five to ten
years will bring about a massive convergence of telecommunications and
computing, placing unprecedented demands on telecommunications
infrastructures worldwide.
New networks generation
In response, we have begun our transition to the broadband era of
communications, a major transformation of not only public switched
telephone networks, but also the Internet, cable TV architectures, and
wireless networks. Broadband networking is the generation of
infrastructure designed for life in the new millennium. This new
generation of networks will support a wide range of end-user
applications with varying requirements for bandwidth, throughput, delay,
variation in delay, reconfiguration intervals, and unique vertical
services.
To satisfy the requirements of future services -- including networked
education, distance learning, telemedicine, electronic commerce,
networked games and gaming, and electronic democracy --
telecommunications networks are undergoing significant functional
changes enabled by advances in transmission, switching, and signaling
technology.
This revolutionary transition includes the deployment of several key
technologies: SONET/SDH, frame relay, ATM, intelligent networks,
broadband local loop, and wireless alternatives.
Fiber-based SONET/SDH infrastructures are replacing the existing PDH
hierarchy (T/E/J Carrier networks) and can support transmission rates
measured in Gbps, with Tbps projected by the year 2000. Among the key
equipment providers we can expect to see at Fall are Alcatel Network
Systems, Fujitsu America, Lucent Technologies, NEC America, Philips,
Rockwell International, Siemens.
Due to the explosive growth of applications (which include high-speed
data, image processing, and networked interactive multimedia), service
providers are seeking to increase the capacity of their existing fiber
optic networks. According to Bellcore estimates, by the year 2000,
bandwidth demand will be 500% greater than it is today.
Enter Dense Wavelength Division Multiplexing -- a combination of optical
multiplexers and optical amplifiers that allow multiple optical signals
to be transported as a group, over a single fiber. Wavelength division
multiplexers offering 20- and even 40Gbps are now available, 80Gbps are
expected in a year, and 1Tbps projected by 2000. Wavelength division
multiplexers (WDMs) now shipping support from four to 32 wavelengths at
2.4Gbps per color. Nortel is trialing an 8-wavelength system based on
OC-192 (9.6 Gbps) elements, and the ITU is standardizing 96-color WDM.
ATM switching technologies, which operate at SONET/SDH speeds and
provide for Quality of Service definitions, are being deployed in all
the major infrastructures, PSTN, Internet, cable TV, and wireless
networks. Key manufacturers include 3Com, Bay Networks, Cisco Systems,
Digital Equipment, Fujitsu, Hitachi, Hughes LAN Systems, IBM, Lucent
Technologies, NEC, Nortel, Siemens, and Standard Microsystems. Virtually
every telecommunications carrier and network operator around the world
has begun the deployment of ATM services.
Frame relay access to ATM backbones will also play an increasingly
important role, enabling cost-effective data networking solutions. Key
providers of carrier switch products include Lucent Technologies, Cisco,
Hughes Network Systems, NEC, and Siemens. Internetwork vendors offering
frame relay products include Bay Networks, Cisco Systems, 3Com, and
Motorola ISG. Voice-over-frame relay products are also available.
Intelligent network architectures will be critical to allowing rapid
service rollout and provisioning, while also providing for
customer-based network configuration. AIN (Advanced Intelligent Network)
platforms operate as servers and are being developed by the
switch/carrier providers, as well as the large computer manufacturers,
including HP, NCR, Nortel, and Siemens. A lower-cost alternative is
programmable switches.
Another major effort underway is the modernization of the local loop,
providing broadband access. One approach taken by a large variety of
telcos is the introduction of high-speed digital subscriber lines, a
variety of techniques affectionately grouped under the heading xDSLs.
These techniques bring new life to the twisted copper pair running into
homes and businesses worldwide. One of these, ADSL (Asymmetrical Digital
Subscriber Line), promises transmission rates of up to 6-8Mbps in the
downstream direction, and up to 640kbps bidirectionally. Chip sets
containing ADSL transmission and MPEG digital compression circuits are
being produced by Motorola, Lucent, and Alcatel. Trials are being run at
20 telephone companies.
Cable modems up to 30Mbps
Another approach to broadband local access is the use of cable modems.
Cable modems can also afford increased downstream transmission rates,
with a potential of up to 30Mbps, albeit shared among the number of
households served by the local node. Cable modem manufacturers include
Motorola and HP. Along with the cable TV operators, hybrid fiber coax
architectures are also supported by Microsoft/TCI.
Finally, developments in wireless networking are finding application in
all telecommunications domains, including PANs, LANs, MANs, WANs, and
GANs, with increasing emphasis on wireless data communications.
Motorola1s Iridium is just one of the LEO (low earth orbiting) satellite
networks that promise to provide end-to-end wireless alternatives to
traditional wireline based PSTNs.
Telecommunications is an exciting industry, a converging market, a
source of competitive power, and the most essential infrastructure of
the knowledge-based economy. Today, no IT solution can be developed
without appropriate knowledge and consideration of communications
infrastructures. For this reason, COMDEX introduces EXPO COMM -- it is
your opportunity to learn about technology fundamentals and recent
developments in Communications: Infrastructure Solutions for the
Knowledge Age.
Lili Goleniewski is president of The LIDO Organization, a provider of
telecommunications education and strategic consulting services, and a
member of the COMDEX Advisory Board.
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