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WIRELESS ALERT & WARNING WORKSHOP Brian K. Daly Director, Network Architecture & Standards Agenda Introduction CMSAAC Update SMS Based Alerts & Warnings How SMS Works Why SMS-based Alerts & Warnings are Problematic Cell Broadcast Technology for Alerts & Warnings Issues with Auto-Dialers
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WIRELESS ALERT & WARNING WORKSHOP Brian K. Daly Director, Network Architecture & Standards
Agenda • Introduction • CMSAAC Update • SMS Based Alerts & Warnings • How SMS Works • Why SMS-based Alerts & Warnings are Problematic • Cell Broadcast Technology for Alerts & Warnings • Issues with Auto-Dialers • Summary
Introduction • Wireless Alerts & Warnings have been extensively studied by many groups internationally, including: • 3GPP • ITU • 3G Americas • GSM Association • General Consensus1: • “There is no one technology that would satisfy all service and performance expectations; multi-channel message delivery is needed.” • “The management of telecommunications capabilities is crucial during disasters that degrade the infrastructure, especially where the infrastructure may have been minimal beforehand. This includes avoiding overload in processing and delivering warning messages, prioritization of calls, network management and provisioning, and infrastructure restoration.” 1 - Joint ITU-T/ OASIS Workshop and Demonstration of Advances in ICT Standards for Public Warning, Oct 2006
Introduction (continued) • Wireless is just one component in an effective public alert & warning system • Technologies available through wireless include: • SMS • Cell Broadcast • Voice calls • In the Future: Multimedia Broadcast & Mobile Video • An effective wireless alert & warning: • efficiently broadcasts the alerts & warnings to the greatest number subscribers technically feasible without significantly adding load to the critical network resources that will result in further network congestion
CMSP Administered C A’ CMSP Gateway Possibly Government Administered Federal Agencies B CMSP Infrastructure Alert Aggregation Local EOC Alert Gateway Mobile Device State EOC Commercial Mobile Alert Service Architecture Critical Function for CMSPs to Deploy CMAS
CMSAAC Issues Under Study • During emergencies, support for National Security / Emergency Preparedness (NS/EP) users and 9-1-1 calls are critical • Need to minimize the potential for Wireless Alerts resulting in severe network congestion that inhibits critical communications • An alert to a wireless device encourages subscribers to immediately use that device • Point-to-point or unicast delivery technologies (i.e. SMS point-to-point, MMS) are not feasible or practical for the support of wireless alerts • Especially on a nationwide, statewide, or large city scale • Point-to-point will quickly congest a network, resulting in significant message delays or messages not delivered, as well as denying voice service
CMSAAC Issues Under Study (continued) • Distribution of the alerts to the wireless subscribers will be unidirectional from the wireless operator network to the mobile device of the subscriber • No acknowledgement or confirmation of receipt by the mobile device in order not to add to network congestion • Do not want to provide phone numbers or links to encourage subscriber to use device for non-essential purposes • Broadcast Technologies (e.g. Cell Broadcast, future MBMS) provide an efficient delivery mechanism for wireless alerts to large numbers of subscribers
CMSAAC Issues Under Study (continued) • CMSAAC has proposed Service Profiles which prescribe the underlying delivery attributes • Text and future streaming audio, streaming video & multimedia • Goal has been to define service profiles and not specific delivery technologies • If an Operator elects to transmit alerts they have the option to use any available technology that supports a given profile • Minimum recommendation for Geo-targeting of alert messages is on a county basis • Service Provider may target smaller areas subject to technology capabilities and operator policy
CMSAAC Issues Under Study (continued) • Only alerts that are immediate, severe, or likely threat to life, health or property will be delivered to mobile devices • Minimize the “cry wolf” syndrome • Commercial Mobile Alerts is a notification service • Limitations on number of text characters that can be broadcast and displayed • Commercial Mobile Alerts are only one component to an overall effective emergency notification strategy • Supplements existing emergency notification systems such as Radio/TV-based EAS and National Weather Service All-Hazards Radio • A common experience across all commercial mobile service providers and technologies is desirable • Common alert tone and/or vibration cadence
CMSAAC Issues Under Study (continued) • Common Alerting Protocol (CAP) is under consideration for the alert origination point to the alert gateway • CAP is not delivered to the mobile device • Battery Life Degradation • Consumers have expectations on mobile device battery life • Commercial mobile alert services could negatively impact those expectations • AT&T is concerned that limited Social Science or Focus Group studies have been performed • What will be the end user reaction to receiving these alert notifications? • End Users “clogging” 9-1-1 or operator customer care services for more information • Reaction when receiving alerts while driving, for example
CMSAAC Issues Under Study (continued) • Service Providers & mobile device vendors should have flexibility in mobile design and implementation of CMA: • take advantage of advances in mobile device technologies • account for the evolution of mobile devices and the capabilities of the future • Provision has been made in the CMAS architecture to support multi-languages • However, a National Plan for languages other then English needs to be developed and the alert must be delivered to the operator in the language to be transmitted
AT&T View on Benefits of A National Commercial Mobile Alert System • Development of a robust emergency alert messaging system for wireless telephony is an ongoing and extraordinarily complex undertaking • Rather than taking an ad hoc approach to such an important and complex public safety initiative, AT&T believes the national process defined in the WARN Act is the most effective way to achieve a robust, sustainable, scalable and reliable wireless emergency alert system for all Americans • The most effective way to address the commercial mobile alert challenge is with the full range of stakeholders at the table and through a nationwide approach that supports local, state, and Federal agencies
AT&T View on Benefits of A National Commercial Mobile Alert System • A National system is crucial to ensure: • Mobile devices and CMA applications are compatible and interoperable throughout the nation • End users traveling or relocating throughout the nation will be able receive alerts with the same device in the geographic area where the alert is issued • Alerts to end users will have the same look and feel nationwide and across CMSPs • Aggregation of alerts from all possible agencies at the local, State and Federal level • A National mobile alert system developed under the WARN Act will provide the fastest path toward a robust, sustainable, scalable and reliable commercial mobile alert service
Some General Wireless Concepts • The wireless network is a shared infrastructure.. • With over 200 million wireless subscribers in the U.S., it is physically impossible to dedicate network resources & radio channels to everyone that has a mobile phone • Given the shared nature of the wireless network, operators must design the networks to handle anticipated traffic loads • Engineering is typically done based on the number of calls & messages during the “busy hour” • Exceeding the “busy hour” causes congestion (“Mother’s Day”) • Congestion leads to blocked calls • “Fast busy tone” • “We’re sorry, you call cannot be completed at this time” • Blocked messages • Resulting in messages being delayed significantly
Minneapolis I35W Bridge Disaster The Minneapolis bridge collapse has illustrated the ironic twist to cell phones: Just when people need them most, they might not work. Cell-phone companies say their networks aren't built to handle the extra load during emergencies. "Jay Reeves, 39, was one of the first people on the scene after the collapse. He tried calling 911, but all the lines were jammed." - Minneapolis Star Tribune, August 6, 2007 - CIO, August 3, 2007 Cell-phone congestion blocked some calls near the collapsed bridge site Wednesday evening, causing Minneapolis police to ask people to get off their phones. Police needed to use the cell-phone networks themselves to mobilize doctors, the Red Cross and other emergency workers who don't have police radios, said James Farstad, a city telecommunications consultant. "Cell-phone networks are not designed for everybody who has a cell phone to use it at the same time," - Minneapolis Star Tribune, August 6, 2007
How SMS works – Step 1 “Find Brian” HLR Message for Brian: Tornado Take Shelter Where Is Brian Last Report @ MSC 1234 Internet Here I am! or Aggregator Message Center Brian Authorized Alert Initiator Message for Brian: Tornado Take Shelter Find Brian MSC “1234” & VLR
How SMS works – Step 1 “Deliver Message” Message from Brian: Acknowledged OK I can get rid of message. No retries needed Message Center Brian Message from Brian: Acknowledged Message for Brian: Tornado Take Shelter MSC “1234” & VLR
Points to Note • The “Find Brian” process is the same whether the network is delivering a voice call or an SMS • Limited number of channels available to “page” subscribers • If paging channels get congested subscribers will miss voice call or SMS pages • The more subscribers there are in a particular cell or sector, the greater the chance of congesting the paging channels • especially in disaster scenarios or trying to send too many SMS messages to that cell/sector • There is a physical limit on the rate at which SMS messages can be delivered on the radio channels • typical rates at which the actual SMS message may be delivered is 2 SMSs per second per sector • If Brian can’t be found, the message center stores the message for later retry
AT&T SMS-Based Emergency Alerts Issues • Message Delays • SMS emergency alert message delivery times can exceed 1 hour, and may require multiple to tens of hours for delivery • Network and radio interface congestion to the point of blocking voice calls • “By examining the Washington, DC, and Manhattan scenarios, it can be concluded that, if SMS were used extensively during a crisis, a significant SMS load could be placed on a network. Individually, the voice load and SMS load are multiple times higher than the engineered capacity at each sector. This analysis has not considered several factors that might increase load, such as messages originating from other sources (e.g., the Internet) and terminating in the congested area. It has also not considered message re-send attempts after failures, which add to network load.” (NCS SMS over SS7, TECHNICAL INFORMATION BULLETIN 03-2, December 2003) • SMS Lacks Security Spoofing and Denial of Service Attacks • “For mobile terminated national emergency messages it would be possible for spam either from a mobile phone or from the Internet to create malicious emergency messages and cause a panic reaction for many mobile subscribers. (ETSI TR 102 444 V1.1.1 (2006-02) • “ability to deny voice service to cities” (“Exploiting Open Functionality in SMS-Capable Cellular Networks”) • Lack of Geographic Targeting
Real-life SMS Alert Experiences • SMS glitch mars testing of new tsunami warning system (Pacific Wave '06 exercise) • Delayed SMS messages in Thailand marred otherwise successful trial of a regional tsunami warning system by dozens of countries across the Pacific. • Of more concern to test organisers was news later that plans to alert emergency coordinators to tsunami threats failed to work in Thailand when busy cell phone networks took hours to deliver key messages. • "The problem we faced was with communications. We have no idea whether our messages sent to local operations chiefs by fax and SMS arrived on time or not, and by midday some of them said they did not receive the SMS," Pakdivat Vajirapanlop from the National Disaster Warning Center told AFP. …. • "We need to know whether they have received our messages. What can they do if the messages don't arrive on time? Then the warning is useless," said Pakdivat, the center's deputy operations chief. • Hoax text message spreads tsunami terror in Indonesia (June, 2007) • Thousands of people fled their homes in panic on the Indonesian coast after hoax text messages spread warning them that a tsunami will hit the region, journalists and officials said Wednesday • "The possibility is that a tsunami may take place on June 7," said part of a short telephone text message (SMS) that is widely circulating in various coastal areas of Nusa Tenggara province, local journalists said.
Real-life SMS Experiences • Finnish Communications Regulatory Authority Working Group Report on Use of Text Messaging in Public Safety Alerts, September 2005 • “The most significant benefit of the SMS system is that an emergency alert sent through it can be received by all mobile stations without any special arrangements. The greatest disadvantage is that the system is slow, and the greater the number of recipients, the greater the disadvantage. ….. It follows that it would take about 1.5 hours to transmit 100,000 messages.” • SMS tsunami rumor hits Sumatra (May 2005) • Rumors that a volcanic eruption had sent a tsunami crashing toward the coast spread through a seaside town on Indonesia's Sumatra Island early Tuesday, prompting thousands of panicked residents to flee to high ground • "It was unclear how Tuesday's rumor began, but it quickly spread by word of mouth and SMS text message, the state news agency Antara Antara reported. By about 2.a.m., almost all the mosques in the town were broadcasting tsunami warnings from their loudspeakers along with religious verses, it said.
AT&T View on Cell Broadcast • Cellular broadcast technologies may eventually provide the best solution for large-scale emergency notification on mobile wireless networks • Near term cell broadcast is text based (“Text Profile” in CMSAAC) • Cell Broadcast is deployed and operated only by the CMSP • “State of the Union” of Cell Broadcast Service (CBS) • Has limited deployments and trials in the U.S. • Most handsets deployed today do not have cell broadcast capability • CBS menus are not visible to subscribers • Software for CBS may or may not exist in the handset • CBS in handsets have never been tested or validated • Future capabilities may include multimedia broadcast • Multimedia Broadcast Multicast Service provides a broadcast capability for multimedia • Maps, video & audio clips, still pictures, graphics, etc.
AT&T Issues with Auto-Dialers • Cellular networks are engineered to support “busy hour” traffic • Not designed to support voice or message traffic for every end user simultaneously • Auto-dialers can easily exceed the “busy hour” traffic load on the network and cell sites • End result is network congestion and potential for critical communications (such as 9-1-1 calls) to be blocked
Summary • AT&T has long recognized and supported the use of wireless technology to promote public safety • AT&T is committed to the CMSAAC development process for a robust, sustainable, scalable and reliable commercial mobile alert service • Emergency Notification System solutions should be carefully evaluated to understand the issues, limitations, unintended consequences, and expectations for end users • AT&T is willing to partner with local and State jurisdictions throughout the CMSAAC process • Recommend all stakeholders participate in the CMSAAC process
"This limit of cell phones catches most people by surprise," said Roger Entner, senior vice president of the communications sector at IAG Research in New York. "They get very upset, but then they forget about it. These are the same kinds of conversations we had with people after September 11." "Regular cell phone service is for regular consumer usage," Entner said. "It was not designed to be the network of last resort, and it would be too expensive to engineer it for that."
WARN Act Overview • “Warning, Alert, and Response Network Act” • U.S. Congress Passed the WARN Act as Part of SAFE Port Act on September 20, 2006 • Signed by U.S. President George W. Bush on Friday October 13th, 2006 • Required the FCC to Establish the Commercial Mobile Service Alert Advisory Committee (CMSAAC) within 60 days of enactment • First Meeting was December 12, 2006 • Membership by appointment of the FCC Chairman • Tasked for development of system-critical recommendations AT&T is an Appointed Member of the CMSAAC and Chairs the Communication Technology Group
WARN Act Milestones We are here Mandated Operator Election Date
Key WARN Act Requirements • Voluntary Commercial Mobile Service Providers (CMSP) are required to make an Election to Transmit or Not Transmit Emergency Alerts in September 2008 • Elections can be “in whole or in part” • If elect not to transmit, must notify subscribers and provide notification at point-of-sale • If elect to transmit, must comply with standards, protocols, procedures, and regulations adopted by FCC • For CMSPs that Elect to Transmit Alerts: • Presidential-level Alerts must be transmitted • May offer subscriber opt-out capability for other classes of alerts • No Fee for Service • Transmission in languages in addition to English to the extent practical and feasible • Liability Protections
Overview of the CMSAAC • Purpose • Develop and submit to FCC recommendations regarding technical standards and protocols to enable participating CMSPs to transmit emergency alerts to subscribers • Recommendations due to FCC one year from WARN Act enactment (due October 12, 2007) • Comprised of a wide range of stakeholders, including representatives from state, local, and tribal governments; vendors, developers and manufacturers; technical experts; other governmental agencies; and wireless service providers
Advisory Committee (approx 40 Representatives) Chair Project Management Group Alerting Gateway Group Alerting Interface Group Communications Technology Group User Needs Group CMSAAC Organization Chairman Martin (or Designee) David Webb (FEMA) Anthony Melone (Verizon Wireless) Brian K. Daly (AT&T) Jonathan Werbell/Gary Jones (NYC/T-Mobile)