1 / 9

Amendment for emergency alert system notification

Amendment for emergency alert system notification. Authors:. Date: 200 8 - 11 - 06. Background (CID 4186).

tala
Télécharger la présentation

Amendment for emergency alert system notification

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Amendment for emergency alert system notification Authors: Date: 2008-11-06 Ding Zhiming, Huawei

  2. Background(CID 4186) Currently within 802.11u draft D4.0, the AP uses a EASN bit to indicate whether or not a higher layer Emergency Alert Message (EAS) is available at the AP for download. The value 1 of EASN bit indicates that a higher layer EAS is in operation, which means that at least one emergency alert message is available. Value 0 indicates that no higher layer EAS is available which means that there is no emergency alert message. When a second alert becomes available, the EASN bit is changed from 1 to 0 and for 1 minute; then changed to 1 so that the non-AP STA will be alerted to re-fetch the information of the new emergency alert. Ding Zhiming, Huawei

  3. According to this current EASN mechanism described in 11u draft 4.0, when a second emergency occurs, the EASN bit will change from 1 to 0 and last for 1 minute and then change to 1 indicating that the new emergency becomes available. Thus, when a new emergency takes place, the alert has to be received after 1 minute or longer. If the emergency is about a severe earthquake, then more people may be injured for this 1 minute. On other hand, if a non-AP STA misses the beacons during the period of EASN bit is changed to 0 from 1, it will still deem that no new alert message becomes available. So the mechanism is not very reliable. Problems Ding Zhiming, Huawei

  4. As a solution, we suggest： Use the EASN field to indicate if any emergencies exist, and add another optional field, called EICI (Emergency Information Change Indication) Octet, to indicate the status and the change of the emergencies. If there is no emergency, EASN is set to 0, and the EICI field does not exist; if there is an emergency(s), EASN is set to 1, and the EICI field appears and its value changes upon the change of the emergencies info. See the following figure: Solution How the EICI field represents the change of emergencies status is further specified in next slides: Ding Zhiming, Huawei

  5. Solution – EICI Field Example • The first emergency occurs: EASN set to 1; EICI appears; EICI set to 1; • Then, the value of EICI increment by 1 upon: a new emergency occurs; or an existing emergency disappears. • If all emergencies are gone: the EICI field disappear • If a new emergency occurs after all previous emergencies are gone: EICI field appears and its value is increment by 1 upon the previous value • After 255 emergency status changes has been counted: the EICI restores to 1. Ding Zhiming, Huawei

  6. Within the current mechanism, the non-AP STA doesn’t know the difference between no current alert message as opposed to never receiving an alert, when the EASN bit is 0. To give more information about the available services to the user, an additional field may be added into the Interworking Element. The new field is one bit length to indicate whether the network supports EASN mechanism: 0 for no support for EASN ; and 1 for supporting EASN. The original EASN bit (B6) may be used for this intent, and the MSB of the optional EICI field (1 octet) may be used to indicate whether any emergency alert exists or not, and the remaining bits of the octet are used as described in the previous slide. The whole format of the new Interworking Element is showed as following figure. Further consideration Ding Zhiming, Huawei

  7. Motion 1 • Move to accept the EASN solution described in submission 11-08-1274-00-000u-Normative_Text_for_Amendment_for_EASN.doc and request the IEEE 802.11u editor to incorporate it into the IEEE 802.11u draft document. • Mover: • Seconder: • Result: • Yes • No • Abstain Ding Zhiming, Huawei

  8. Motion 2 • Move to add a field into the Interworking Element to indicate whether a network supports EASN described in submission 11-08-1275-00-000u-Normative_Text_for_Amendment_for_EASN.doc and request the IEEE 802.11u editor to incorporate it into the IEEE 802.11u draft document. • Mover: • Seconder: • Result: • Yes • No • Abstain Ding Zhiming, Huawei

  9. END Ding Zhiming, Huawei

More Related