Wide-Area Optical Fiber Network Monitoring and Management System
by Kunihiro Yamamoto *, Masahide Ogawa *, Tetsuhiro Yamashita * and Masao Sasaki *The optical fiber cable networks that form the backbone of high-speed
communications are increasingly being laid using the vacant spaces along
rivers and roads, and in sewer conduits. This requires a system that can maintain and control,
efficiently, accurately and on a nation-wide scale, the changing conditions of cable installation
and usage for each fiber. It is to respond to this need that we have developed a wide-area opticalfiber network monitoring and management system, to provide maintenance and control of opticalfiber networks.

ABSTRACT1.

INTRODUCTION

The installation of optical fiber cables has proliferated
with society’s increased demand for telecommunications
equipment, forming increasingly complex networks oflines. The areas where these are installed now cover thewhole of Japan, and cables, which initially consisted ofjust a few optical fibers, and then a few dozen fibers each,have now reached 1000 or more fibers in each cable.
This has brought massive increases in the amount ofequipment.
Stable operation of these growing optical fiber networks
requires efficient and accurate maintenance and controlof the equipment as a whole and of each individual item.
There is also a need for round-the-clock monitoringof optical fiber line networks, rapid and accurate pinpointing of the location of any fault that might occur,and prompt restorative action. Accordingly at Furukawa
Electric we have developed, as a means of maintaining
and controlling optical fiber line networks, a monitoringand management system 1)~3) which offers a monitoring
function to detect faults such as increased loss, and amanagement function to create a database of information
pertaining to optical fiber line equipment that can be easily
searched.
These monitoring units and control units are mainly
installed in outstations, and are primarily for operations
at the individual outstation level. For this reason, in asituation in which optical fiber networks are growing
and expanding throughout the country, it has become
necessary to investigate several outstations as a meansof determining the situation in equipment that are spreadover long distances, and so to configure an optical fiber*

OMM System Dept., Optcom Div.

network monitoring and management system on a nationwide scale.
Accordingly we have developed here a wide-area
optical fiber network monitoring and management systemthat achieves, on a nation-wide scale, a grasp of the fiber
usage situation in optical fiber line equipment, connection
information, system information etc. for equipment control,and monitoring of fault information. This paper provides an
overview of the system thus developed.

2.

SYSTEM OVERVIEW

2.1 Configuration
This system comprises optical fiber line monitoring units(hereinafter referred to as monitoring units), optical fiberline control units (control units), optical fiber line central
control units (central control units), and optical fiber line
regional control units (regional control units). These units
are connected by LANs or WANs. Figure 1 shows theoverall system configuration, and each of the units is
described as follows:(1) Monitoring units: These comprise measuring units
and monitoring units installed in outstations, etc., andcentral monitoring units installed in block stations,etc. A monitoring unit displays the location of any fault
that may occur in the optical fiber line on the system
diagram etc., and transmits fault information to thecentral monitoring unit and control units. The central
monitoring unit collects monitoring results from eachof the monitoring units to which it is connected, andwhen there is a fault, displays the fault information.
(2) Control units: These are installed in outstations.
They aggregate the results of measurements fromthe monitoring units, and when notice of abnormality

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Wide-Area Optical Fiber Network Monitoring and Management System

Central station

Regional control unit

Block station

Block station

Central monitoring unit

Central control unit

Central cotrol unit

Unified central monitoring/control scheme

Outstation

Discrete installation scheme

Outstation

Monitoring unit

Control unit

Control unit
Discrete installation scheme

Unified monitoring/control scheme

Measuring unit

Figure 1

Overall system configuration.

information is received from a monitoring unit,
pinpoint the fault location and display it on the map.
They have the functions of searching, displaying andupdating fiber connection information, equipment
information and map information.
(3) Central control units: These are installed in theblock stations, etc. They have the functions ofsearching and displaying fiber connection information,equipment information and map information underjurisdiction within block stations. They have thefunction of acquiring data on the manufacturers andtype designations of equipment and on the namesof the companies using lines that are recorded in theregional control units.
(4) Regional control units: These are installed in thecentral stations, etc. They have the functions ofsearching and displaying fiber connection information,equipment information and map information for thewhole country. They have the function of recording
and updating data on the manufacturers and typedesignations of equipment and on the names of thecompanies using lines that are used in common
nation-wide.
2.2 Features(1) Enables search and display of equipment
information on a nation-wide scale: The
manufacturers and type designations of equipment
and the names of the companies using lines that areused in common throughout the nation are recorded
as unified data in the regional control units. The
central control units access the regional control unit,
acquire the recorded names, and then use the names
at the control units where input/output operationfor equipment data are carried out, thereby making
it possible to use names that are in common use
throughout the system, and to search equipment
information on a nation-wide scale.
(2) Enables smooth search and display of information
spanning outstations: A configuration has been

adopted whereby jurisdictional equipment data under
the jurisdiction of block stations are controlled in a
unified manner at the control database of the central
control unit, not of each control unit, and equipment
data is not dispersed for each outstation, so that byorganizing equipment data between outstations, it ispossible to achieve smooth searching and display forline information spanning outstations.
(3) Aggregates fault information from each outstation:
Central control units are installed at outstations
and the fault information at each control unit isaggregated, making it possible for fault information to
be ascertained separately for each block station.

3.

MONITORING UNITS

3.1 Configuration
Figure 2 shows the configuration of a monitoring unit.
Since the optical fiber being monitored is connected via aterminal box, each monitoring device is installed in close
proximity to the terminal box. In outstations in which an
operator is present, a monitoring unit is installed, and in a
block station, a central monitoring unit is installed.
3.2 Functions
The measuring unit uses an optical time domain reflectometer (OTDR) to make measurements sequentially andat fixed intervals with respect to optical fiber losses in theroute that is targeted for monitoring, which passes throughthe fiber switching section and was previously designated,and by comparing the difference between the normal
condition and the time at which measurement faults in the
optical line are detected.
The monitoring unit aggregates control andmanagement of the measuring unit and the results ofmeasurements taken by the measuring unit, and by
previously recording the connection point information,
when it receives a fault transmission from the measuring
unit, quickly pinpoints the location of the fault, andFurukawa Review, No. 24

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Wide-Area Optical Fiber Network Monitoring and Management System

Measuring unit
Operating section
Measuring/processing section

Communication interface

Monitoring unit

Central monitoring unit

Monitoring unit proper

Central monitoring unit proper

Communication interface

Communication interface

Pseudo line section
Fiber switching section
Measuring unit

Measuring unit

ClosureTo control unit

Immersion sensor

Terminal box

Terminal box

Figure 2

Table 1

Configuration of monitoring unit.

Main functions of monitoring units.

Function
Automated monitoring

Description

Contact point output

Table 2

Minimum specifications of control uit hardware.

Hardware item

Control unit

Automated monitoring at specified intervals

Fault detection and pinpointing Display of information on position of fault
Manual monitoring

Table 3

Memory512 MB

CentralRegional

control unit

control unit

512 MB

512 MBCPU

32 bits

32 bits

32 bits

operation

Hard disk

18 GB

100 GB

100 GB

Route, unit abnormality

CRT monitor

17-inch17-inch17-inchStorage

DAT

12 GB*

12 GB

12 GB

deviceMO

640 MB*640 MB*640 MB*

Monitoring of any desired line by manual

Main display functions of central monitoring unit.

* Add-on

Description
1

System diagram

2

Names of equipment (block station, outstation, etc.)

3

Fault route, fault point distance, fault history

Application section
Engine section

transmits the fault information to the central monitoring
unit and the control units. Table 1 shows the mainfunctions of the monitoring units.
The central monitoring unit carries out periodic
monitoring of each of the monitoring units connected to it,
aggregates the monitoring results, and, when there is fault
information, collects the route of the fault and displays thefault information. Table 2 shows its main display functions.

4.

CONTROL UNITS

4.1 Configuration
Table 3 shows the specifications for each type of control
unit. The central and regional control units use the highly
reliable RAID 5 server. DAT is provided as standard forthe backup of important data.
Figure 3 shows the structure of control unit software.
The operating system used is Windows NT/2000, andFurukawa Electric Information Technology’s EyeKernel-X
is used as the map engine. The database engine isOracle. In this environment a newly upgraded version of
Furukawa Electric Information Technology’s Eyepack-NET
fiber control software is used. The central and regional

Operating system:

Figure 3

Fiber control software: Eyepack-NET
Map engine:
EyeKernel-X

Database engine:
OracleWebserverWindows NT/2000

Structure of control unit software.

control units are provided with a web function, enablingsearch and display from operating terminals that can beconnected by LAN.
4.2 Functions
The control data can, depending on its attributes,
be modeled in three groups--equipment installation
information, system diagram information and attributeinformation. Equipment installation information consistsof data on line equipment installation--manholes (MH),pylons, conduits, etc. System diagram informationconsists of data on closures other than that whichis related to geographical position, cables, and theconnection conditions of each. Attribute information is
information on each individual fiber and data on thecondition of each connection point. Each of these levels isconnected by a relational key.
Using this relational key, information on the cables
and closures accommodated in equipment such as

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Wide-Area Optical Fiber Network Monitoring and Management System

Attribute information(connection point information,
information on each fiber individually)

System diagram information(closure information, cable information)

Topographicalinformation

Planar information on installationof plant and equipment(MH, pylon, conduit, span information)

Figure 5

Display to alert of occurrence of fault.

Overlapping display ofcontrol data and map data

Figure 4

Table 4

Relational diagram of data.

Main functions of control units.
Function and Description

Update functions
Updating the equipment diagram and installations of equipment in
the system diagram

Figure 6

Display of fault location.

Updating attribute information for each item of equipment
Updating fiber connection configurations for junction boxes
Search & display functions
Searching point of installation by means of the equipment diagram
Searching & displaying line equipment by means of the equipment diagram
Searching equipment passed by a specific fiber
Searching circuit (route), searching dark fiber
Searching junction box fiber connection configurations
Searching fibers in use
Searching desired conditions (search by name or specification)
Searching & displaying dark fibers and routes by setting for startand end points
Outputting CSV data for search results

manholes or conduits can be searched at the control
units, and further searching is possible, even to fiber
information. And superimposing these search results
and topographical map information produces an easily
understood display of the conditions of line installation.
Figure 4 is a relational diagram of the data, and Table 4shows the main functions of the control units.
4.3

Coordination Between Monitoring and Control
Units
When a line fault occurs in the line being monitored,
the control unit is notified via the monitoring unit of thefault information, together with an alarm, and a variety
of information is displayed on the map by operation,
including display of the location of fault occurrence.
Figure 5 shows an alert screen at the time ofoccurrence of fault trouble. Clicking on the “confirm”
button causes the location of the line fault to be displayedon the map (Figure 6). From the screen displaying thefault location it is possible to confirm the location of fault
occurrence, the name of the conduit (between manholes)

or of the span (between pylons) containing the cable inwhich the fault is thought to have occurred, and the lengthof that conduit or span, the name of the accommodating
equipment nearest the fault location (name of manhole orpylon), the distance from that location, and so on. Thus
when the fault occurs in a conduit, it can immediately
be ascertained how far past which manhole should be
investigated, and in addition it is possible to display the
waveform measured by the measuring unit, the extent
of the effect when it is determined that all fibers havebroken in the cable incorporating the fiber in which afault was monitored, and to display a listing of the cables
incorporating the location of the equipment incorporating
the fault concerned.
4.4 Functions of Central Control Unit
The central control unit treats the central control unit asa database server and the control unit as a client, andoperates as a client server system. In this system, in orderto process the maximum amount of data, attention ispaid to the response time with respect to screen displays,
and when in construction, etc., data entry or updating isfrequent and is dispersed or distributed, equipment data,
the organizing of which is difficult, is loaded to the central
control unit and subjected to unitary management, anddetailed map data, for which updating opportunities arerare and data volumes large, are loaded to the control
unit, thereby improving response. Figure 7 is a conceptual
diagram showing the data flow between a central control
unit and a control unit.
Backup is achieved by continual replication of thecontrol data in the central control unit by the control unit.
Thus if there is a circuit fault or the like between thecontrol unit and the central control unit rendering thecontrol database of the central control unit inaccessible,
there is the capability of switching over to the backup data

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Wide-Area Optical Fiber Network Monitoring and Management Systemand continuing operation, so that no interference with theoperations at the outstation level will occur.
The central control unit also has a search and display
function with respect to the optical fiber line equipment
under the jurisdiction of block stations that is similar tothat of the control units. It is, for example, possible to
make the name of a road or river into a single key, andperform search and display for a road that runs between
outstations. Figure 8 is a typical search screen.
Here the equipment concerned are displayed in alisting. By clicking on the attribute buttons, equipment
diagram buttons and system diagram buttons for theequipment that are to be displayed from this screen, it

Centralcontrol unit
Database<Data from central control unit to control unit>= Equipment attribute data, topographical data, etc.
· When search/display is carried out at a control unit
· When control data section is updated for backup at acontrol unit

<Data from control unit to central control unit>= Equipment attribute data, topographical data, etc.
· When data is input for the first time or updated at acontrol unit due to construction, etc. of an opticalfiber line

4.5 Regional Control Unit Functions
The regional control unit allows the recording andupdating of data on the manufacturers and typedesignations of equipment and on the names of thecompanies using lines that are used in common
throughout the nation. These names are recorded at theregional control center as unified master data. From theunified master data of the regional control unit, the central
control unit generates pseudo unified master data, andwhen data is entered at a control unit, it accesses thecentral control unit and selects the required data from thepseudo unified master data, so that its content is unified
throughout the nation and searching on a nation-wide
scale is possible.
The regional control center is also able to perform
search processing for line equipment nation-wide, butwhen the search is carried out at the regional control
unit, it automatically determines the central control unit
on which the control data to be searched is loaded, anddirects the server of the central control unit to generate
the required data. By receiving this control data, it ispossible to perform search and display for line equipment
nation-wide.

5.

Control unit

Figure 7

is possible to display a equipment diagram on which
attribute information such as the conditions of use of thefibers connected to the plant or equipment, connection
information and route information, and the situation inwhich the equipment are installed are shown graphicallyon a map, and a system diagram in which the situation ofcable connections are shown linearly.

Data flow between central control unit
and control unit.

CONCLUSION

The system presented here has been delivered to the
Ministry of Land, Infrastructure and Transport, and has
begun operation. It is intended to investigate the extent towhich updated equipment data can be efficiently applied
to the system, and to improve performance to respondeffectively to users' needs.

REFERENCES

Figure 8

River name search screen.

1) Yamashita and Hasemi; Supporting System for Optical Fiber
Installation Work, Furukawa Electric Review, No. 103, 1998,
13. (in Japanese)
2) Sakemi et al.; Application of GIS to Management Supporting
System of Optical Fiber Transmission Line, Furukawa
Electric Review, No. 107, 2001, 45. (in Japanese)3) Umezaki and Sato; Development of Management andSupervisory System of Optical Fiber Transmission Line. (inJapanese)

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