10

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日本バーチャルリアリティ学会誌第 17 巻 1 号 2012 年 3 月

東日本大震災を振り返って

特集 ■ 東日本大震災を振り返って

東日本大震災時における情報通信ネットワークの状況と分析
Telecommunication Status and Analysis of Information Network Systems
on East Japan Great Earthquake

柴田義孝
Shibata Yoshitaka

岩手県立大学内田法彦

埼玉工業大学

Uchida Noriki

大橋裕司

Go Forward Japan

Ohashi Yuji

Abstract— East Japan Great Earthquake on March 11 in2011 caused severe damages over the wide area of Northern
Japan. A massive 9.0 earthquake destroyed many buildings
and information systems, and a devastating tsunami swept overcities and farmland in the northern part of the country and set
off warnings as far away the west coast of the United States andSouth America. Also, the large-scale earthquake brought thesecondary disasters such as blackout, fire, and nuclear crisis.
Many information network systems are also severely damaged
with the East Japan Great Earthquake. Compared with the recent
historical severe earthquakes in Japan such as Hanshin-Awaji
Great Earthquake in 1995 and Chuetsu Earthquake in 2004, there
were many different types of problems because of the recent highly
developed information society. They were the congestion of cellar
phone, the lack of fuels and electricity, and so on.
In this paper, the problems of information network systems
on East Japan Great Earthquake are analyzed, and thesolutions of these problems are discussed. Through our network

Figure 1 JMA Scale (Shindo) by Japan Meteorological Agency

In the aspects of major earthquake in world history, it was the
fourth largest earthquake next to Great Chile Earthquake in 1960
(M9.5), Great Alaskan Earthquake in 1964 (M9.2), and Indian
Ocean Earthquake and Tsunami in 2004 (M9.1) [2]. Moreover,reconstructing activity just after the earthquake, the connection of
information network is the most important other than throughput
or latency for disaster information system. In fact, satellite
system, wireless LAN, and cognitive wireless system were usefulfor the reactivating network connection in the disaster area.

this large-scale earthquake also brought the serious secondary
disasters such as blackout, fire, and nuclear crisis.
TABLE 1 LARGE SCALE EARTHQUAKE IN THE WORLD

Keywords-component; Disaster Information Network; East
Japan Great Earthquake; QoS;

Year
1960

1. INTRODUCTION
East Japan Great Earthquake on March 11th in 2011 caused
severe damages over the wide area of Northern Japan, and there
are still many problems for reconstructing activities in the disasterarea. A massive 9.0 earthquake destroyed many buildings andequipment, and a devastating tsunami swept over cities and coast

1964

2004

resident’s area in the northern part of the country. This tragedy wasshocked to the world, and about 15,841 dead and 3,490 missing
persons are still increasing even today [1].

2011

1952

10

2010
1906

DisasterGreat Chile
Earthquake in 1960
Great Alaskan
Earthquake
2004 Indian Ocean
earthquake andtsunami (off the west
coast of northern Sumatra)
Japan Earthquake andtsunamiKamchatka
earthquake
Great Chile
Earthquake in 2010
Ecuador-Colombia
earthquake
Rat Islands

Magnitude

Fatalities

9.5

2231

9.2

131

9.1

220000〜

9.0

Death15,841. Missing
3,490 (at12/21/2011)

9.0

0

8.8

525

8.8

1000

Great Chile
Earthquake in 1960
Great Alaskan
1964
特集 東日本大震災を振り返って
Earthquake
2004 Indian Ocean
earthquake and2004
tsunami (off the west
coast of northern Sumatra)
1960

2011

1952
2010
1906
1965
2005

Japan Earthquake andtsunamiKamchatka
earthquake
Great Chile
Earthquake in 2010
Ecuador-Colombia
earthquake
Rat Islands
earthquake, Alaska
2005 Sumatra
earthquake, Indonesia

9.5

2231

9.2

131

9.1

220000〜

9.0

Death15,841. Missing
3,490 (at12/21/2011)

9.0

0

these problems are discussed. Through our network reconstructing
activity just after the earthquake, the connection of information

8.8

525

network is the most important other than throughput or latency
for disaster information system. In fact, satellite system,

8.8

1000

wireless LAN, and cognitive wireless system were useful for the

8.7

0

8.6

1346

JVRSJ Vol.17 No.1 March, 201211

reactivating network connection in the disaster areas.
In the followings, in section 2, network conditions of various
information systems on East Japan Great Earthquake are reported.
Section3 deals with the problems with and by information network
systems on the earthquake. Then, it discussed about internet
usages on the earthquake at section 4. Finally section 5 derived
discussions and future works of information network system on alarge-scale disaster like East Japan Great Earthquake.

However, the earthquake also caused many problems otherthan such a major secondary disasters. The problems about
information network systems are also serious by the East Japan
Great Earthquake. Compared with the recent historical severe
earthquakes in Japan such as Hanshin-Awaji Great Earthquake in1995 and Chuetsu Earthquake in 2004, there were many different
types of problems because life style have been dramaticallychanged by the recent highly developed information society. Cellar

2. NETWORK CONDITIONS OF INFORMATION NETWORKSYSTEM ON EAST JAPAN GREAT EARTHQUAKE
East Japan Great Earthquake caused many problems suchas rescue, food distribution, and evacuation. Malfunction of
information network system was a part of major problems after

phone system have been greatly increased during several years,
and the damage and congestion of cellar phone caused serious
problems for rescue, life safety information, food distribution andso on. The lack of disaster information is considered with thereason of these activities’ delay. Moreover, the lack of fuels andthe earthquake. Especially, the lack of disaster information suchas life safety, damages, and so on brought much confusion ofvarious activities. The following table 1 is the summary of various
information systems’ condition in Iwate Prefecture through our
network relief activities.

electricity may cause the delay of rescue and support activities forthe evacuators.

TABLE 2 NETWORK CONDITIONS OF VARIOUS INFORMATION NETWORKSYSTEM ON EAST JAPAN GREAT EARTHQUAKE

Under this disaster, Iwate Prefectural University located in
the middle of Iwate Prefecture could barely have the electricity
and network functions because of the backup systems, and Ph.
D. Shibata and their staffs have worked for the support activities
based upon their previous studies of Disaster Information Systems
for earthquake, tsunami, typhoon, and so on. Iwate Prefecture
is located in the northern part of Japan, and one of the severe
damaged area including Miyagi and Fukushima Prefecture.
Especially, the coast side cities of Iwate such as Rikuzentakada,
Ofunato, Kamaishi, Otuchi, Miyako, and so on were seriously
damaged by the great tsunami disaster. The area scale of Iwate is
15,200km, and this is the second largest prefecture in Japan. The
population is about 1,370,000 and the most of area is consistedof the mountain area and the Coast of Pacific Sea. According to
the Ministry of Internal Affairs and Communications in Japan,
broadband and internet adoption rate’s ranking is 46th and 45thout of 47 in Japan [3], and there are still some unavailable areasof cellar phone around the mountain and coast side. Historicallyspeaking, there have been many disasters such as earthquakes,
tsunami, volcano, and storm in winter in this prefecture, andtherefore the disaster activities are considered to be well prepared

SystemRadio

Conditions

TV×

Fixed phone

×

Cellar phone(audio)Internet(Cellar phone)
Iwate Information
Highway(Government’s
Information
Network System)
LAN in City Hall
Disaster
Government Radio
SystemAmateur Radioand trained in comparison with other areas. However, the largescale disaster caused 4,696 death and 1,663 missing person in theprefecture.
In this paper, the problems of information network systems on
East Japan Great Earthquake are analyzed, and the solutions ofWireless LAN
11

Satellite system(internet)○

Details
Small area service suchas local FM radio was
useful for evacuators.

△

It did not worked
because of wide area’s
blackout.
Devices were damaged
and blackout
Highly congested△

Highly congested

×

Broke down networkand devices.

×

Broke down networkand devices.
Unable to hear inside ofhouse or car.

△

○

○

○

Worked but only a few
devices and licensed
users
Worked but electricity
was needed
Worked(Government’s
Information
Network System)
日本バーチャルリアリティ学会誌第1 号 2012
年 3network
月
12LAN
in City Hall× 17 巻Broke
down
and devices.
Disaster
Unable to hear inside of△Government Radiohouse or car.
SystemAmateur Radio○
Worked but only a few
devices and licensed
users
Wireless LAN
Satellite system(internet)

○

○

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東日本大震災を振り返って

broadband internet service, and even the local government network
system were unable to use. The public web services and email

Worked but electricity
was needed
Workedsystems in Iwate Prefecture was also down, and it may affected tothe isolation of the coast cities in Iwate.
However, there were some information network systems

One of the major problems of information network systems
was the rapid growth of cellar phone system in today. According
to Ministry of Internal Affairs and Communication, numbers of
telecommunication on cellar phone became about 10 times as theconsidered as useful in disaster area. In the case of network relief
activities in the coast side of Iwate, satellite system for internet
such as IPSTAR and wireless LAN were useful for reactivating
network communication systems. Although there were problems

usual just after the earthquake, and the maximum limitation ofaudio communication became up to 95% which is the meaning that
only one user could used the service out of 20 persons. [4]about electricity, both systems were used for the reactivating insome evacuation shelters and disaster headquarters quickly. The
following picture is about the network relief activities in Taro,
Miyako City.

Figure 2 Numbers of calls by cellar phone (au) on 3/11/2011 (the Northern Japan)

Figure 4 Satellite Configuration in Taro, Miyako City

Figure 1 shows the congestion of cellar phone system in thenorthern part of Japan where is heavily damaged by the earthquakeon 3/11/2011. The figure showed the numbers came up to about

Although satellite system does not have high quality network
condition like FTTH, the major contents under the emergent
situation were text-based contents such as email, web based life
safety information, and SNS. Therefore, satellite system waspractically useful even such an emergent situation. Wireless LAN
was also practically worked for temporal LAN reconstruction.
Since the inside of public buildings such as city hall was damagedby the disaster,

8 times as the usual in the disaster area, and the maximum
congestion was about 30 minutes after the earthquake. Moreover,figure 2 is about Tokyo, Japan. Compared with figure 1, there
were two peaks about 15:30 and 18:00 on 3/11/2011, and thenumbers were about 10 times as the usual communication. In
case of Tokyo area, whole public transportation was stopped
and there were many peoples who could not come back to homearound 18:00. That is considered as the reason why Tokyo has twocongestion peaks from the data.
Thus, a cellar phone became hard to use after the earthquake,and it caused serious communication problems wide area of Japan.
As the results, not only by the damages of network devices but
also the congestion of cellar phone is considered with the reasons

It is also said that radio, especially local FM station, was verypractical in evacuation shelters. Since most of evacuation sheltersand headquarters didn’t have electricity, radio was the only way
to method to know about disaster information. However, theneeds of the evacuators was mainly the small local informationsuch as evacuation shelters, food distribution, hospital, life safety
information around them, so information from major radio and TV
station is said that they were not so practical for the disaster area.
With information network relief activities in the coast cities in
Iwate, the important thing was considered as the connectivity of
network system and electricity for disaster information on a largescale disaster. Therefore, future disaster information system needs
such robust network connectivity by satellite system and wirelesswith the serious lack of disaster information such as about rescues,
evacuation shelter, life safety, and so on.
Moreover, in the disaster area such as the coast city in Iwate,
many wired networks and servers on information network systems
were break down by the huge tsunami. Therefore, fixed phone,

network system.

Figure 3 Numbers of Calls by cellar phone (au) on 3/11/2011 (Tokyo)

3. PROBLEMS ON EAST JAPAN GREAT EARTHQUAKE
From 18th of the March, the authors’ network relief activities
were held in the severe damaged coast side cities of Iwate. At that

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東日本大震災を振り返ってJVRSJ Vol.17 No.1 March, 201213

time, there was still less information in the coast side of Iwate evenafter a week passed from the earthquake. Although tragic tsunami

Japan), but the rate was greatly decreased until about 20% just after
the earthquake. This is because many internet service in Tohoku

news were on aired, phones or email communication did notconnect with the cities.

area was unable to use by the damages and congestion. Then,it takes about from one to two weeks to reactivating temporal

The followings are the equipment for reactivating the

network services around Morioka, Iwate.

communication network through the activities.
(1) Disaster Center in Miyako (3G network, 5PCs3)(2) Disaster Center in Iwaizumi (3G network, 5PCs)(3) Taro City Hall (Satellite, 7PCs)

In case of temporary houses for evacuators, the most location
was originally no internet service area like mountain side, so
temporal communication cables were needed to construct for thearea. Therefore, there are still many temporal house area where(4) Green Peer Taro (3G network, 2PCs, Printer)(5) Green Peer Taro Aiina (3G network, 2PCs, Printer)(6) Miyako City Hall (3G network, 2PCs) , and so on

internet service cannot be used in now. However, satellite systemand FWA are used for those area by Ministry of General Affairs,
and internet services are spreading now.
Local governments also had to construct temporal internet
cables because their LAN and internet cables were damagedby the tsunami. They reconstructed temporal cables for thecommunication with prefectural office, and began their works fora while after the earthquake. Moreover, the most servers at local
governments in Iwate were damaged, and so disaster information
was not informed to the residents in Iwate. Therefore, they came

However, there were many problems in the activities. First ofall, gas for track was difficult. Lack of gas had been spread towhole northern and middle Japan, and the car line of waiting gas
became over 3km long around IPU. Secondary, sudden lower
temperature made mountain roads frozen. It is clear that lack of
information and frozen road made the delay of rescue activities forthe coast side area.
The followings are major problems of our network relief
activities.
(1) Fuel for cars was difficult to get.
(2) Electricity and battery for information network system was damaged(3) Network devices and servers were damaged(4) Wired networks were disconnected(5) Cellar phone system was damaged and congested(6) Government Disaster Radio System was break down
(7) TV could not be watchedto share disaster information by using internet such as twitter andblog in a couple of days after the earthquake.
Medical services also used internet for temporal communication
between local hospitals and central hospitals. Not only evacuation
shelters but also all local hospitals and central hospitals weredisconnected for communication in Iwate. The use of internet
temporally reconnected between shelters, local hospitals, andcentral hospitals.
Volunteers are used internet for many their activities. They
were the sharing of disaster information by SNS, name’s lists inevacuation shelters by picture images on web broads, possible roadconditions on GIS, and so on. Compared with the other previous
Japanese earthquake, there were many new trials by using internetby the volunteers on the earthquake. Because of IT developmentsof these days such as smart phone, wireless broadband services,(8) Many evacuation shelters used papers for life safety informationand disaster information.

Web services, and SNS, the use of internet for disaster isconsidered to be getting important.
5. USEFUL SYSTEMS FOR TEMPORAL REACTIVATINGINFROMATION NETWORK SYSTEMS
Although there have been many problems on East Japan Great
Earthquake, there were many information network systems
in practice for temporal network reactivating. This could be
important for the future studies of disaster information system.
Major useful network systems in network relief activities in Iwate
are the followings.
● Satellite IP system (IPSTAR) quickly recovered internet
communication in many disaster areas.

Figure 5 Trafic Jam by waiting for A Gas Station

Therefore, those problems should be concerned for the future
study of disaster information system.

● Available area of cellar phone had been gradually spread.
● The router consisted of 3G and wireless network (IEEE802.11
b/g/n) was used for many city halls and evacuation shelters in
temporal.
● Wireless network (IEEE802.11 b/g/n) could be used for covering

4. INTERNET USAGE ON THE EARTHQUAKE
Many information network systems didn’t work after theearthquake, but Internet is used for the various ways for many
activities on East Japan Great Earthquake. Internet adoption rate
was 74.7% before the earthquake in Tohoku area (the northern

13

14

3/14
AM

Gas stations, public
transportation (bus),
secondary disaster, lifeline(electricity), life 特集
safety information.

Damages around
Takizawa andMorioka.
東日本大震災を振り返ってLife safety
information.

3/14
PM

Gas stations, public
transportation (bus andrailway), secondary
disaster, lifeline(electricity), life
safety information.

Damages around
Takizawa andMorioka.
Life safety
information.

3/15
PM

Gas stations, publicLife safety
transportation (bus,information.
railway, highway, roads
conditions for Tokyo),life safety information,
food (rice, bread).
Disaster information
Life safety
around the coast side of information.
Iwate, Gas stations,public transportation(bus, railway, highway,
roads conditions forTokyo), life safety
information, food (rice,bread, noodles).
Restaurant, public bath Life safety
house, gas station,
information.
public transportation, life Delivery of relief
safety information, road goods.
and gas information forthe coast side, food (rice,bread, noodles).

日本バーチャルリアリティ学会誌第 17 巻 1 号 2012 年 3 月

disaster area quickly.
● Satellite phone system was fully used (each local city government
possessed about two phones.)● Cognitive wireless router (NiCT) was useful. [5]● Twitter, blog, and SNS was practical for realtime information
sharing such as gas station, transportation, foods, and ATM.

3/16
PM

The authors’ team was also use twitter for sharing disaster
information in Takisawa and Morioka area in Iwate. Table 3 issummary of the disaster information by twitter on the activities.
TABLE 3 SUMMARY OF NEEDED INFORMATION

Needed information
around IPU

Needed informationfrom other area

3/12
AM

Shelters, food
distribution, public
transportation, medical,
stores, life lines,
entrance exam.

Damages around
IPU, Takizawa, andMorioka

3/12
PMBank and ATM, possible Damages aroundplaces for charging
IPU, Takizawa, andcellar phone battery,
Morioka. Life safety
electric stores, gas
information
stations, Shelters, food (seeking persons)distribution, public
transportation, medical,
stores, life lines

3/13
AM

Gas stations, stores,
Damages aroundbank and ATM, possible Takizawa andplaces for charging cellar Morioka.
phone battery, life line
Life safety(electricity), electric
information.
stores, public
transportation, medical.

3/13
PM

Gas stations, stores, life
safety information, alertof secondary disaster,bank and ATM, lifeline(electricity), electric
stores, public
transportation, medical.

Damages around
Takizawa andMorioka.
Life safety
information.

According to this table, it is understood that electricity, cash,
and fuels were important for evacuators after shelter and foodinformation was needed. Since most of internet services andservers were unable to use for a couple of weeks, the role ofinternet usage was important for communication and sharing
disaster information in Iwate.

3/14
AM

Gas stations, public
transportation (bus),
secondary disaster, lifeline(electricity), life
safety information.

Damages around
Takizawa andMorioka.
Life safety
information.

3/14
PM

Gas stations, public
transportation (bus andrailway), secondary
disaster, lifeline(electricity), life
safety information.

Damages around
Takizawa andMorioka.
Life safety
information.

6. DISCUSSION AND FUTURE STUDY
Network infrastructures have been recovering in Iwate evennow, but there are still more problems that must be considered withthe reconstruction of disaster area. The followings are parts ofmajor subjects that should be considered for the reconstruction in
information network systems.

3/15
PM

Gas stations, public
transportation (bus,railway, highway, roads
conditions for Tokyo),life safety information,
food (rice, bread).

Life safety
information.

3/17
PM

3/18
PM

Restaurant, public bath Life safety
house, gas station,
information.
public transportation, life Delivery of relief
safety information, road goods. Volunteers
and gas information forthe coast side, food (rice,bread, noodles).

Later

Road and gas
Life safety
information for the coast information.
side, food (rice, bread,
Delivery of relief
noodles), employment
goods. Volunteers.
information for students, Secondary disaster.
aftershock.

● To raise the quality of livings in temporal houses● Information systems for life and reconstruction information● Medical Information System for residents (Especially for the
reducing work time of medical doctors in the disaster area)● Health condition check for residents (Physical and mental conditions)

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東日本大震災を振り返ってJVRSJ Vol.17 No.1 March, 201215

● Remote observation system for elder persons● Employment information system for residents[5] National Institute of Information and Communications Technology,“Construction of Cognitive Wireless Router in Disaster Area”,● Education system for students, and so on

http://www.nict.go.jp/press/2011/04/13-1.html[6] Japan Meteorological Agency, “Report of Past Great Earthquake

In this paper, the problems of information network systems onaround Japan,” http://www.seisvol.kishou.go.jp/eq/higai/

East Japan Great Earthquake are analyzed, and the solutions ofthese problems are discussed. Through our network reconstructing
activity just after the earthquake, the connection of information
network is the most important other than throughput or latency

higai1996-new.html[7] Takehiko TAKANO, “Overview of the 2011 East Japan Earthquake
Disaster,” The 2011 East Japan Earthquake Bulletin of
the Tohoku Geographical Association, 9 April, 2011,

for disaster information system. In fact, satellite system,
wireless LAN, and cognitive wireless system were useful for thereactivating network connection in the disaster area.

http://wwwsoc.nii.ac.jp/tga/disaster/articles/e-contents7.html
BIOGRAPHY
Yoshitaka Shibata received his Ph.D. in Computer Science fromthe University of California, Los Angeles (UCLA), U.S.A. in
1985. From 1985 to 1989, he was a research member in Bell
Communication Research, U.S.A., where he was working in
the area of high-speed information network and protocol designfor multimedia information services. Since 1998, he is working
for Iwate Prefectural University, Japan as an executive director

ACKNOWLEDGMENT
We have generous support from student support room’s members
in IPU, Dr. Akihiro Yuze in Shizuoka Prefectural University, Dr.
Kaoru Sugita in Fukuoka Institute of Technology, Saitama Instituteof Technology, Japan Science and Technology Agency (JST), GFJ,
KDDI, and Coretec co,. LTD for our activities.

of Media Center and a professor of Faculty of Software andInformation Science in the same university.

REFERENCES[1] Japan Police Department, “The Great East Japan Disaster. ”
http://www.npa.go.jp/archive/keibi/biki/index.htm.
[ 2] Japan Meteorological Agency, “Past Reports of Earthquake

Noriki Uchida received his Ph. D. in Software and Information
Science from Iwate Prefectural University in 2011. From 2011

and Tsunami,” http://www.seisvol.kishou.go.jp/eq/higai/higai1995.html[3] Ministry of Internal Affairs and Communications, “2010White

he is working for Saitama Institute Technology as an associate
professor. His research interest includes wireless networks,
cognitive networks and disaster information network.

Paper Information and Communications in Japan”, http://
www.soumu.go.jp /johotsusintokei/whitepaper/h22.html[4] Ministry of Internal Affairs and Communication, “About How
to Secure Communication Systems on Emergent Affair such as
A Large Scale Disaster”, http://www.soumu.go.jp/main_sosiki/
kenkyu/saigai /index.html

Yuji Ohashi worked for Nippon IBM as a system engineer from1974 to 2010. He is working for Go Forward Japan as a directorof Non-Profit Organization. His research interest includes disaster
information network.

15