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Türkiye advances with its UYARSIS, while Japan has outdone itself in the realm of Disaster Roaming

Istanbul, 2023

Burak Yuva - Defne Telekomünikasyon AŞ

Emergency warning systems are a crucial component of ensuring public safety. Nations prone to extreme conditions (like excessive weather or climate changes) are strongly advocating for this system in order to guarantee public safety.

As the destructiveness and harmfulness of natural disasters increase in the world, the need for warning systems has emerged. That’s why Public Warning Solution (PWS) comes into prominence, it mitigates the risk of deaths and damages. This system (PWS) was established by ETSI and it was desired to be standardized with some mobile technologies CMAS, EU Alert, KPAS, and EMA to name a few. In conclusion, two main systems that may be underlying technologies for PWS, SMS and CBS (Cell Broadcast Service). [1]


SMS is a well-known and used messaging system across the world, it is generally more effective in one-to-one messaging. PWS requires bulk messages to alert the public rapidly. In any emergency, there might be congestion due to an increase in traffic on the networks, and a high potential for delays. SMS might have trouble in meeting this condition because it sends a message directly regardless of location. There is no certainty the receiver is available to get the message properly which leads to confusion. Therefore SMS is less compatible with PWS as its working principle.

· Possible delays might occur due to congestion when a vast amount of messages should be delivered to subscribers

· The solutions used by many countries deliver the SMS based on the user’s phone number, but not specific locations, hence the high possibility of not getting the alert messages while roaming in the alert area. Except for Türkiye. Türkiye’s UYARSIS differentiates from the others with its capability to send SMS based on location (region, city, town). Check out Türkiye’s Emergency SMS solution here

Cell broadcast systems rely on locations to work with PWS. Critical alerts and messages are sent by CBS to particular regions, thus regardless of being a host or guest, every individual can get the messages. Since it is supported by all devices such as IOS and Android, the rate of usage has expanded dramatically. According to the figures indicated by Dutch Government, the successful delivery of alert messages is 94%. In addition, there are key features that make CBS more practicable as a PWS.

· Delivery: Since CBS is based on broadcasting principles, message delivery to small areas and even large areas is quick.

· Display: The message can be shown on the handset without user intervention, and a separate warning tone can be heard. It can also convey messages in a variety of languages.

· Security: There is no requirement for receivers to register the system hence they stay anonymous in the database. Another significant fact is users may rely on the message content since it is sent and authorized by the government.

CMAS (Commercial Mobile Alert System)

CMAS was first established by FCC in response to WARN (Warning Alerting Response Network) after 2006. The CMAS system is designed to format, confirm and authenticate the locally incoming alert messages and transmit them to the appropriate gateways of mobile operators. Alert messages are categorized in 3 ways and transmitted by CMAS: Presidential, Imminent Threat, and Amber alerts. The CMAS architecture is outside the scope of 3GPP’s responsibilities,3GPP mainly focused on covering receptions thanks to CBC and distributing them to the mobile devices which are CMAS capable. The major purpose of CMAS is to avoid the threat to the health and properties of people. For the cell broadcasting system (CBS) to take an active role in PWS, it is remarkably crucial that is standardized by the entire world otherwise, the application would be troublesome. The problem stems from various handsets that are currently used in the world. Furthermore, most of the PWS implementations monitor CMAS implementations in a manner it provides standardization by the clients. As more mobile alerting systems like CMAS become available in the U.S. market, it will become more common for device manufacturers to include the feature on new models. In the Netherlands, CMAS-based clients are deployed by several manufacturers as CMAS and EU-Alert are compatible. [2]

Different types of PWS:


In this section, the public warning systems implemented in Europe are investigated. Emergency Communications (EMTEL) and European Public Alert System (EU-ALERT) are discussed in the article prepared by the European Telecommunications Standard Institute (ETSI). With the announcement of the implementation of the cellular broadcast alert system by the Netherlands in 2010, it entered into projects funded by the European Commission. EU-ALERT is the general term for the European Public Alert Service. Some countries use the letter EU by replacing it with their country identification letters. For example; NL-ALERT is the term for the Netherlands, UK-ALERT is for the UK, and FR-ALERT is for France. This strategy allows each country to configure its own General Warning System to meet its particular national requirements, adhering to a common core specification. Spread to life with a strong belief in a multi-channel approach, first implemented by the Netherlands in Europe and by the Dutch government Public Alert Service, ending with a warning to consumers through channels such as siren systems, radio and television, internet, SMS , and social media. Countries within the European Union are considered as a whole within the scope of integrated border management. Therefore, general warning messages in different languages should be sent to subscribers for the European General Warning System. The Cell Broadcast Service (CBS) system must be used to meet the requirement that messages be broadcast almost simultaneously in multiple languages so that any recipient of a message in a particular language is not disadvantaged. ETSI TS 123 041 document sets the standard for assigning message identifiers for local language EU-Alert messages that are in the same range as English CMAS messages.

J-Alert (Japan) :

In the case of natural disasters such as earthquakes, typhoons, and tsunamis, which are constantly seen in Japan, studies have been carried out to detect the disaster before its arrival and to promptly evacuate the people by early warning time, and in this context, the system called "J-ALERT" has been established. The J-ALERT system is operated by the Fire and Disaster Management Agency, established under the Ministry of Internal Affairs and Communications of Japan. Emergency teams were established after the Kobe earthquake in Japan. These teams act according to the commands given by the FDMA and the FDMA plans and programs are carried out by the Prime Minister. The J-Alert emergency warning application implemented in Japan consists of several components. The sensing systems include satellites, national and local control stations, and terminal terminals. Earthquake sensors are used to detect earthquake risk. Water level indicators are used to detect the tsunami risk that may occur in the oceans. Since there is an urgent risk in the systems used, it is immediately transferred to the satellite systems. Emergency warning notifications coming to the satellite are transmitted to the control stations on land. It has been successfully implementing the J-ALERT early warning system, which works as a satellite-based system, since 2007.

AirWave (England) :

Airwave provides voice and data transmission to government workers performing critical tasks such as police, fire, ambulance services, local authorities, and transport providers providing vital public services. The Airwave network is the first public service network in the world to provide secure and seamless communication between emergency services and emergency response teams. Based on Terrestrial Trunked Radio (TETRA) technology provided by Motorola Solutions, it covers 99% of Great Britain's landmass and allows different public service agencies to communicate with each other.

FR Alert (France) :

Fr alert is a system developed by the Ministry of Interior to alert people by sending messages in affected areas. The system is entrenched on CBS, hence the notifications are not sent by SMS in order to prevent congestion on the network. To make this system possible, telecom antennas were used and messages were broadcasted with the help of radio waves. FR-Alert is intended to notify people in a danger zone using telecommunications networks. As a result, no prior registration is required to get notifications or to download a mobile application.[3]

Uyarsis (Türkiye) :

The purpose of Uyarsis is the determination of the issues related to the establishment and operation of the national mobile warning system, which allows users to receive warning notifications in geographically specific regions in case of disasters, emergencies, and situations that may pose a threat to public order, national security and national cyber security. Within the scope of this regulation, during disasters and emergencies, it is ensured that the citizens are immediately warned in cases that may pose a danger, with appropriate methods such as the Mobile alarm system (Commercial Mobile Alarm System - CMAS), SMS, CBS, and pre-call announcement, and the necessary measures are taken. It is aimed to be received in a timely and effective manner. Warning notifications to be made with the CMAS method is categorized by four channel; state alert notification, vital alert notification, loss/hijacking alert notification, and test alert notification. With the regulation, “Warning notifications made with the CMAS method are automatically sent to all users in the geographical area notified by the authorized user through the system. The establishment, operation, and use of UYARSIS are carried out in cooperation with the relevant public institutions and organizations, under the coordination of BTK. Users coming from abroad within the borders of Türkiye can also be warned in case of disasters and emergencies with CMAS and CBS methods. Check out Defne'ss CBS solution here. [4]

A. Communication systems post-earthquakes

Communication failures can lead to widespread damage and deaths, so it is important to understand how systems behave under harsh conditions in order to design more resilient technologies. Communication systems are important to a community's resilience in the face of catastrophes, such as earthquakes, hurricanes, and tsunamis. By providing access to important information and helping people take preventative measures, communication systems play a critical role in disaster management.

1. How communication systems fail during natural disasters

· Congestion

· Infrastructure damage

· Component destruction

2. Incidents

a. Japan earthquake 2011

Japan was struck by a massive earthquake in March 2011 and a massive tsunami shortly thereafter. This resulted in extensive damage and fatalities. An earthquake, a tsunami, and a nuclear crisis all occurred simultaneously during the Japan earthquake, making it a three-in-one catastrophe. It is the largest earthquake in Japan's history, with widespread damage and fatalities. The tsunami warning system notified the public shortly after the earthquake was detected. Thermal energy stations, television and radio broadcasts, fixed and cell phone administrations and outside interchanges were seriously harmed. Blockage caused high utilization limitations, and instant messages were bound to arrive at their objective. At the conclusion of this crisis, proposed technical solutions can be utilized worldwide for effective disaster preparedness and response. [5]

Photo by: Mainichi Shimbun / Reuters

· Use voice message services rather than voice calls to prevent network congestion

· Offer backup for crucial Base Transceiver Station

· Use buried cables rather than aerial cables

b. Silivri Earthquake 2019 (Türkiye)

In the earthquake of 5.8 magnitudes in Istanbul on September 26, 2019, telephone networks became inoperable. After the earthquake, which did not cause any loss of life and did not cause huge damage, communication was entirely stopped, except for data transmission over the Internet. Although there was no loss, the cessation of communication revealed many problems for a telecom operator in Türkiye. The Board of Electrical Engineers (EMO) made a written statement on September 27, 2019, and evaluated the interruption of communication after the earthquake in Istanbul. Emphasizing that privatization causes inadequacies in the communication infrastructure, the statement also requested the establishment of emergency communication systems that will provide uninterrupted communication and satellite communication in regions where transportation is very difficult. The statement discusses inadequacies in the communication infrastructure and building inspection and recommends that the government establish an integrated combat system with the participation of all organizations, invest in bandwidth, and create emergency communication systems. It also recommends that early warning systems be disseminated throughout the country, that illegal construction and unhealthy urbanization be prevented, and that studies be conducted to raise awareness of disaster preparedness from preschool through all stages of life. Finally, EMO says that the situation of assembly areas after a disaster is uncertain and that they must be arranged in an installable way so that they can be instantaneously accessible and provide shelter from a disaster.

Photo by: Elif Öztürk - Anadolu Agency

Developments following these suggestions;

  • Early Warning System: Türkiye, especially Istanbul, is seen as a risky earthquake zone due to the fault lines it hosts. Therefore, it is important to develop a system that can predict earthquakes. Türkiye first implemented the tsunami and earthquake warning system in 2021. This system is located in the Büyükçekmece province and can prevent possible earthquake and tsunami disasters. It will help to anticipate and take a position accordingly. Since this system will observe the movements in the earth's crust, it was established together with the GPS station. The aim here will be to keep many processes from observing the sea level to the observation of meteorological events, and with the help of this, it is aimed to get rid of possible disasters with the least damage.

AFAD -Türkiye, Disaster Ready School-Preschool Education for Disaster Awareness: This education aims to raise awareness and consciousness from an early age and to gain basic behaviors and skills against the threatening disaster risks in the country. Education for kindergarten students is supported by games and presentations. The education, which is carried out with technical equipment consisting of a computer, projection, and sound system in the classroom environment, is offered to student groups of 20 students in an interactive way. The education program, prepared in line with the interest periods and learning styles of the preschool age group, is supported by games and cartoons.

Disaster Roaming

In the event of a disaster, mobile networks may have trouble providing service. However, the user can still have the service during a disaster if the PLMN operator is willing to provide the service. Minor service outages are limited to certain times and locations. Disaster roaming allows the UE to access disabled PLMNs in the event of a disaster. If no other PLMN is available, it provides a resource-efficient way for the PLMN to inform visitors in a roaming disaster if they can use the PLMN. The 5G system and EPS support a mechanism by which the HPLMN checks whether a UE with an HPLMN subscription should use disaster roaming. So in any case of network failure due to a disaster, Disaster Roaming would be a solution. To give an example of this situation recently, it can be mentioned that KDDI’s network failed in Japan. As a result, approximately 39 million subscribers were deprived of making emergency calls. If disaster roaming had been used, such an unfortunate situation would have been averted.

Example Procedure

1. WSP A evaluates the affected area after the event and determines that roaming is required


2. Then WSP A tries to connect to WSP B for the roaming implementation.

3. The next step is an acknowledgment of the request which is running by WSP B. Furthermore, WSP B transmits network information to WSP A if the network can handle the extra demand. WSP B performs the required procedures to enable roaming and relays this information to WSP A. WSP A verifies roaming on the network of WSP B.

4. Both WSP A and WSP B have mutual contact to inform each other whether the network gets any damage or not. They can both terminate the roaming at the right time. While one of them intends to end the roaming, it has to give notice as it ends.[6]

CMAS post-earthquake usage areas

U.S :

CMAS was first used in the USA in 2012. The reason for its use here was an unexpected tornado in the Elmira region of New York. Although it has only just begun to be used, all people in that region received quick warning notifications thanks to CMAS. Apart from that, CMAS was also used when Sandy Hurricane took place, most people received warning notices but there have been a minority that did not.[7]

Türkiye (BTK) :

BTK is the telecom authority in Türkiye and creates regulations for certain procedures. The purpose of this regulation [8] is the determination of the issues related to the establishment and operation of the national mobile alert system, which allows users to receive notifications in geographically specific regions in case of disasters, emergencies and situations that may pose a threat to public order, national security and national cyber security.

Notifications are to be made by the CMAS method; They can be made in three different categories as state-level warnings, warnings about vital risks, and loss/abduction announcements.

(1) Notifications made with the CMAS method are automatically sent to all users in the geographical area notified by the authorized user through the system. It is not possible to prevent receiving notifications in the "State-level alerts" category, but receiving notifications in other categories can be left to the users' choice.

(2) The title of the messages regarding the notification categories is determined by the Authority.

(3) CMAS method enables notifications with multi-language support.

(4) The frequency of repetition of the notifications to be made by the CMAS method and the time between repetitions are entered into the national mobile alert system by the relevant authorized user.

(5) Notifications can be made on the basis of geographical region, province, district, and area selected by the relevant public institutions and organizations.

(6) Audio warning, visual warning, vibration warning, etc., in order to make it easier for disabled and elderly subscribers to receive notifications. methods are used.

(7) Notifications can be made with a minimum length of 160 characters and a maximum of 360 characters.

(8) The operator publishes the notifications sent by the authorized user via the CMAS method, to be forwarded to the users by processing them within a maximum of 1 minute following the completion of all approval processes in the notification approval process.

(9) The operator is obliged to provide the notifications to be made by the CMAS method at a minimum level of 95% for each calendar year in accordance with the ninth paragraph of this article. [8]


Many aspects of how states and society should act in possible natural disaster scenarios have been discussed, ranging from raising social awareness to infrastructure improvement. Many aspects of how states and society should act in possible natural disaster scenarios have been discussed, ranging from raising social awareness to infrastructure improvement.

The most emphasized subject here is early warning systems and mobile technologies used in these systems. In addition to the possible advantages and disadvantages of these technologies, where and how they are used is also very important, and as a result, it is important to analyze the widespread use of these technologies or which technology can be approached to possible disaster scenarios. For example, disaster roaming can be used in possible network outages, so that many lives or structures survive the disaster with minimal damage.

SMS should not be ignored even though it has been applied less in warning systems recently compared to CMAS. However, incoming warning messages do not disappear from the inbox and people can see this warning again. SMS can also be used to inform certain areas (regions, cities, towns, etc.) in case of a crisis. Here, it is important to get the list of the target location and the subscribers who are located in this target location. As a result, it is possible to inform a certain region with the help of SMS in a short time. Also, possible congestion problems are prevented with automatic pace management, in this case, TPS is reduced or increased.

A different issue in early warning messages is how much people know and apply them, where it is especially important to inform and educate the public about early warning systems. As a result, if we need to emphasize the importance of the public warning system once again, it plays a saving role in many situations, especially in human life, and there is no doubt that it will have many benefits.

About Defne: Defne, is a leading global provider of telecom solutions, software products, and services for communications networks.

Defne offers a differentiated portfolio of innovative call completion and management, messaging and notification, roaming, and digital services solutions. Today, more than 25 service providers across 20 countries serving over 500 million subscribers are driving revenue growth and increasing customer loyalty with Defne’s solutions and services. Expertise in 5G, IN, IVR, messaging, mass notification, and public warning solutions combined with a wealth of skilled resources, allows Defne to provide reliable and scalable solutions that seamlessly integrate with existing customer infrastructure.


[5] : EL Khaled, Z., & Mcheick, H. (2019). Case studies of communications systems during Harsh Environments: A review of approaches, weaknesses, and limitations to improve quality of service. International Journal of Distributed Sensor Networks, 15(2), 155014771982996.


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