I was just looking at that also.
https:// www.fema.gov/news-release/2011/05/10/personal-localized-alerting-network
What is PLAN?
The Personal Localized Alerting Network (PLAN) is a new public safety system that allows customers who own an enabled mobile device to receive geographically-targeted, text-like messages alerting them of imminent threats to safety in their area.
This new technology ensures that emergency alerts will not get stuck in highly congested user areas, which can happen with standard mobile voice and texting services. PLAN enables government officials to target emergency alerts to specific geographic areas through cell towers (e.g. lower Manhattan), which pushes the information to dedicated receives in PLAN-enabled mobile devices.
PLAN complements the existing Emergency Alert System, which is implemented by the FCC and FEMA at the federal level through broadcasters and other media service providers. Like the Emergency Alert System, which is a modernization of the earlier Emergency Broadcast System (1963-1997), PLAN is intended to keep up with new technologies that can keep Americans safer. This modern, integrated and complementary alert system provides significant public safety roles for broadcasters, cable service providers, wireless service providers and other service providers.
Wireless companies volunteer to participate in PLAN—technically called the Commercial Mobile Alert System (CMAS). PLAN is the result of a unique public/private partnership between the Federal Communications Commission (FCC), the Federal Emergency Management Agency (FEMA), and the wireless industry with the singular objective of enhanced public safety.
The Warning, Alert and Response Network (WARN) Act requires participating wireless carriers to activate PLAN technology by a deadline determined by the FCC, which is April 2012. Participants that will offer PLAN ahead of schedule include AT&T, Sprint, T-Mobile, and Verizon.
How Does It Work?
Authorized national, state or local government officials send alerts regarding public safety emergencies, such as a tornado or a terrorist threat, to PLAN.
PLAN authenticates the alert, verifies that the sender is authorized, and sends it to participating wireless carriers.
Participating wireless carriers push the alerts from cell towers to mobile phones in the affected area. The alerts appear like text messages on mobile devices.
Features
Geographically Targeted: A customer living in downtown New York would not receive a threat alert if they happen to be in Chicago when the alert is sent. Similarly, someone visiting downtown New York from Chicago on that same day would receive the alert.This requires a PLAN enabled mobile device and participation by the wireless provider in PLAN.
Customers Automatically Signed Up: PLAN allows government officials to send emergency alerts to all subscribers with PLAN-capable devices if their wireless carrier participates in the program. Consumers do not need to sign up for this service.
Alerts Are Free: Customers do not pay to receive PLAN alerts.
Covers Only Critical Emergency Alerts: Consumers will receive only three types of alerts from PLAN: (1) alerts issued by the President; (2) alerts involving imminent threats to safety of life; and (3) Amber Alerts. Participating carriers may allow subscribers to block all but Presidential alerts.
Unique Signal and Vibration: A PLAN alert will be accompanied by a unique attention signal and vibration, which is particularly helpful to people with hearing or vision-related disabilitie…