5 Earthquake and Tsunami Warning System

22.2683GPPPublic Warning System (PWS) requirementsRelease 18TS

5.1 Background

Warning Notifications are expected to be delivered to the users while satisfying the following requirements:

– Quick Warning Notification delivery after the occurrence of Earthquake or Tsunami.

Earthquake and Tsunami propagate very fast. The duration time between the actual occurrence of the disaster and its arrival is very short. The order of the duration time is around seconds or minutes at most. Therefore the Warning Notifications shall be delivered quickly to the users in the emergency impacted area so that they could take any actions to escape from danger.

– Accurate Warning Notification delivery.

Warning Notification delivery urges the users to take the actions such as evacuation. Therefore, the Warning Notification shall be delivered to the users accurately in the Notification Area and the content of Warning Notification should be understandable for many types of users (i.e. impaired persons, foreigners).

5.2 Duration of delivery time

Duration of the delivery time for PLMN operators is the time from the receipt of the Warning Notification by the PLMN operator, i.e. the edge of the 3GPP network, to the time that the Warning Notification is successfully delivered to the UEs.

Provisioning of delivery of Primary and Secondary Notification may be required:

– Primary Notification shall be delivered within 4 seconds to the UE in the Notification Area even under congestion situation.

– Secondary Notification is delivered to the users in the Notification Area even under congestion situation.

Note 1: UEs that are out of coverage or switched off are not considered in the requirements.

Note 2: Secondary Notification may not always be generated as it depends on the Warning Notification Provider’s policy.

Note 3: Primary Notification may not always be generated (i.e. the warning may start with a Secondary Notification).

5.3 Information element and volume

The following are the requirements from the perspective of information element and amount of data.

Both Primary and Secondary Notification shall:

– support at least 2 types of emergency events, which are Earthquake and Tsunami;

– be able to indicate the preferred UE behaviours when receiving Warning Notification, (e.g. whether to display text in the foreground, whether to ring a buzzer, whether to vibrate);

– be distinguishable from notifications generated for the purpose of testing, training and other notification services;

– be sent in an optimized type and amount of data, for example, a text with a certain length, by considering the delivery platforms for ETWS.

Primary Notification shall:

– convey data which is small enough to be sent quickly on the network.

– convey small amount of data to indicate the imminent occurrence of Earthquake and Tsunami, etc.

Secondary Notification may:

– convey a large amount of data in order to deliver text, audio to instruct what to do / where to get help, graphical data such as a map indicating the route from present position to evacuation site, time table of food distribution.

Note: The amount of data to be sent within a Primary Notification would be a few bytes to achieve quick information delivery.

5.4 Priority

Requirements from the perspective of priority are as follows:

– Primary Notification has higher priority than Secondary Notification.

– Notifications shall be able to be sequenced by the PLMN according to priority of notification in case that Primary Notification and Secondary Notification should exist at the same time in PLMN.

5.5 Roaming users

Upon receiving Primary Notification which includes small amount of data to indicate the imminent occurrence of an Earthquake and/or Tsunami, the UE shall display the Warning Notification in a way that is easy to understand by the user, such as an icon or picture.

Note: It is expected that that the Warning Notification Provider will send the Warning Notification in the languages in common use in the specific area or in such a way that the Warning Notification can reasonably be understood.