LTE: What is the main difference between ETWS and CMAS public warning system ?

Question

I was going through 36.331 specification, SIB10, SIB11 are used for ETWS and SIB12 is used for CMAS i.e Commercial Mobile Alert System. As per my understanding, both comes under the public warning system. Can anyone please explain the major differences between these two ?

Answer 1

ETWS - Earth Quake and Tsunami Waring System.

CMAS - Commercial Mobile Alert System.

ETWS is broadcasted to all the devices by network provider to alert about natural Disasters. ETWS in SIB10 and SIB11 are for primary and secondary level of notifications about disasters.

CMAS is for commercial Advertising purpose. Its completely different from ETWS.

Comments

The standard allows for sending two alerts. ETWS for sending fast, simple alerts and CMAS for slower more content-rich followup information. CMAS, known as Wireless Emergency Alerts (WEA) in the U.S., is used by FEMA's IPAWS system to send AMBER and other alerts. ETWS has not yet been implemented in the U.S. but is used in Japan and Europe.