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NTT2000
Practical Applications of Systems for ATM Backbone Network ......... 15 Economically Upgrading Submarine Transmission Systems

to 10 Gbit/s
�
4 ch Using WDM Technologies .................................. 15 Unidirectional Optical ADM Ring System for Multi-Point

Broadband Communications ............................................................. 16 MAPOS Networking ---Supercharge the Internet ................................ 16 Planning Tool for Estimating Costs of Transport Networks ................ 17 The World's First Field Test of a 40-Gbit/s/channel WDM

Signal Transmission over an Installed Dispersion-Shifted Fiber .......... 17 Support for Introduction of WDM-Phase
..........................................
18 Development of Coded OFDM Technologies .................................... 18 Development of Wideband FWA (Occupied Band)

Using Sub-Millimeter-Wave and Millimeter-Wave Bands .................. 19 Software Radio System Featuring Service/System

Reconfiguration Through Software Changes .................................... 19 Wide-LAN Service ............................................................................. 20 Asymmetric Digital Subscriber Line ...................................................... 20 Dedicated Service Handling Modules (DSM) for

Constructing Economical Leased Line Networks .............................. 21 Development of a Software Tool for Evaluating Network Reliability ..... 21 Cost Reduction Technologies for MU Fiber Optic Connectors .......... 22 Development of a 1300-nm-Band Optical Fiber Amplifier Module ..... 22 Guidelines for Preventing Accidents in Power-Supply Systems ........ 23 Free Space Aperture Line Technologies for Simplified Line Routing ....... 23
CONTENTS
Telecommunications
Network Technologies
Technologies for establishing a base network infrastructure including
satellite, wireless, and optical networks, all of which are essential to
guaranteed bandwidth and broadband telecommunication. 15
Telecommunications Network Technologies
Practical Applications of Systems for ATM
Backbone Network
NTT Laboratories have been promoting development of various types of
systems (model A/B/C, NE-OpS
*1
) for ATM
*2
backbone network, in order to
respond flexibly to the rapidly increasing demand for multimedia, and on
purpose to reduce costs by integrating networks that in the past had been
created individually for each service. Files were released was at the end of
June 1999, and the system was applied in Megalink and other services
from October of the same year.
In order to allows the system for ATM backbone network to be applied in
a number of different services, for this system consist of three types of
equipment and equipment operation systems ---Model A (node system),
Model B (link system), and Model C (access system)--- and have as basic
functions the ability to support various types of QoS
*3
class as well as to
support various types of reliability measures, including section and VP
*4
protection. Model A, which has a function that controls and manages ATM-
related services, controls the PVC/SVC
*5
. Model B has a VP cross-con-
nect function to ensure efficient path accommodation in the optic fibers.
Model C has a function that efficiently accommodates ATM-related ser-
vices. Concentration between Model C and Model A is carried out using
SNI
*6
technology, so it is also possible to provide SVCs economically.
At the same time, a network operation system (ANIMA
*7
) was developed
(at the current NTT East and NTT West Research and Development Cen-
ter) to allow us to operate these three types of equipment as a single unit.
In this way, it is possible for us to uniformly carry out such functions as
circuit monitoring and control, circuit opening, and receipt of failure notifica-
tions.
ATM backbone network can be developed as the backbone network of-
fering, from existing ATM-related services to future SVC services, various
types of multi-QoS that support diverse QoS levels, and for IP
*8
services.
In the future, we will continue to increase the performance of this sys-
tem, adding new functions including support for new services, and improv-
ing maintenance and operation functions even further than before.
(Network Service Systems Laboratories, Access Network Service
Systems Laboratories)
*1
NE-OpS: Network Element-Operation System
*2
ATM: Asynchronous Transfer Mode
*3
QoS: Quality of Service
*4
VP: Virtual Path
*5
PVC/SVC: Permanent Virtual Channel/Switched Virtual Channel
*6
SNI: Service Node Interface
*7
ANIMA: ATM Network Integration Manager
*8
IP: Internet Protocol
Configuration of systems for ATM backbone network
Economically Upgrading Submarine Transmission
Systems to 10 Gbit/s
�
4 ch Using WDM Technologies
The communication capacity of backbone networks has increased
dramatically in keeping with the growing demand for the Internet and
other forms of multimedia communication. As a result, there have
been considerable efforts made to find economical ways to increase
the capacity of submarine optical fiber transmission systems, which
are an important method of achieving high-capacity communications
on submarine cable routes.
NTT Laboratories have developed a system that economically
achieves high-capacity transmission in the FSA
*1
submarine optical
fiber transmission system, originally intended for single wavelength
channel transmissions, which is installed between Kagoshima and
Okinawa. This has been accomplished by making only the land-based
equipment compatible with the shift to WDM
*2
, while using the Sub-
marine facilities (optical fiber cables and optical repeaters), which ac-
count for most of the capital investment, in their original form. This
system was developed based on the results of field tests carried out
by NTT Laboratories on the route targeted for the new application. It
features a flexible and economical system configuration that makes it
possible to increase the capacity of the existing transmission system,
from 10 G
�
1 wavelength per fiber to a maximum of 10 G
�
4 wave-
lengths. In order to make this substantial capacity increase possible,
we have applied the following: (1) a high-speed forward error correc-
tion technology for 10-Gbit/s systems; (2) a pre-emphasis technology
for optical transmission; and (3) PRZ
*3
transmission pulse and wave-
length dispersion compensation technologies that can suppress the
waveform distortion caused by fiber nonlinearity and dispersion. The
system's monitoring and control carries over the supervisory meth-
ods used by the existing optical repeaters, and so allows the same
ease of operation as the existing single wavelength channel trans-
mission system, while at the same time offering independent monitor-
ing and control for each separate wavelength. In addition, we have
achieved single fiber-pair 4-wavelength channel transmission using a
two-bay mount with a compact equipment design.
In the future, we will promote increases in the communication ca-
pacity and the economy of submarine optical fiber transmission sys-
tems and networks.
(Network Service Systems Laboratories)
*1
FSA: Fiber Submarine Transmission using in-line Optical Amplifier
*2
WDM: Wavelength Division Multiplexing
*3
PRZ: Partial-Return-to-Zero
Increasing capacity of submarine transmission systems using WDM Technologies
Individual Service OpS
ATM Network OpS (ANIMA)
Model C
Model B
Model A
Standard interface
Standard interface
Standard interface
Standard interface
Standard
interface
Standard
interface
Model C
NE-OpS
Model B
NE-OpS
Model A
NE-OpS
Standard
interface
(S/T point) Multiple services accommodated uniformly Concentrated in a nearby location by user (more economical than installing a S/W) Increased economy in subscriber section High-speed transfer VP cross-connect High-speed optical
interface Uniform control of multiple services SVC (signal) control QoS control Uninterrupted file renewal Three-layer configuration: System OpS/Network OpS /NE-OpS Integration and unification of ATM-NW management
ONT
10Gbit/s
10Gbit/s
10Gbit/s
10Gbit/s
10Gbit/s
10Gbit/s
10Gbit/s
10Gbit/s 4 1 2 4 1 2
Terrestrial
Transmission
System
Section
Terrestrial
Transmission
Equipment
Land -Based
Equipment
Optical
Mux
Optical
Demux
Submarine
Optical
Repeater
Land -Based
Equipment
Terrestrial
Transmission
Equipment
10Gbit/s
�
1 Wavelength
10Gbit/s
�
4 Wavelength
1
, 2
,, 4 Single-
Wavelength
Transmission
System
WDM
Transmission
System
Submarine
Transmission
System
Section
Terrestrial
Transmission
System
Section
Submarine
Optical
Repeater 16
Unidirectional Optical ADM Ring System for
Multi-Point Broadband Communications
Backbone networks and regional networks in the information age
will need to have the capability of transmitting an exceedingly large
signal volume of several hundred Gbit/s with low cost and minimal
delay. To handle signal volume of this magnitude with conventional
electric-signal processing systems , however, hardware size would
need to be excessively large and this would not be efficient from the
standpoints of cost and delay time. By using the optical ADM
*1
ring
system, low-cost and small-delay operation can be achieved by opti-
cal signal processing of DWDM
*2
signals.
In this system, signals with different destinations are allocated by
their respective wavelengths, and optical ADM nodes