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Communications Inc. Public Emergency Alerts Over Cellular Phones …The Challenges. Gyles Panther 6 November 2003. Basic Alerts, Requirements. Primary Notification (Alert) Instruction / Direction Calm and Inform Interactive Management Situation Analysis. Basic Alerts, Suitability.
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Communications Inc Public Emergency Alerts Over Cellular Phones …The Challenges Gyles Panther 6 November 2003
Basic Alerts, Requirements Primary Notification (Alert) Instruction / Direction Calm and Inform Interactive Management Situation Analysis
Basic Alerts, Suitability Primary Notification (Alert) Instruction / Direction Calm and Inform People Management Situation Analysis
The Issues • What constitutes Wireless • Addressing Geographical Regions • Network Issues (Carrier) • Alerting Issues (Alertee) • HandSet Issues (Phone) • Implementation
Wireless Networks • Cellular- GSM / TDMA / CDMA / IDEN • Paging- One Way (POCSAG / FLEX)- Two Way (REFLEX / Data Networks) • Data Networks- Mobitex / Ardis • New cellular data capabilites- GPRS, 1xRTT • Chosen Focus is Cellular
Normal (Voice) communications • Network : locates handset by registration • Control channel sets up comms • Single phone Address i.e. One to One • Cannot address One to Many • No intrinsic mapping of cells to location • Cells variable in size
Alert Transmissions • Address ALL, i.e. Broadcast • Registration irrelevant • Geographical Address • Alert Message Transmitted Digitally • Message Content :- Displayed Text ( Language? ) - Spoken ( Language?) - Displayed ( Video +Speech, language? )
Data Over Wireless • GSM GPRS…Packet data service 170kb/s raw; 40kb/s Usable ? EDGE…Enhanced GSM packet data 384kb/s raw; 60kb/s Usable?UMTS…3G Packet data service: 2Mb/s raw; 144kb/s Usable? • CDMA1xRTT…Basic CDMA packet: 144kb/s raw; 60kb/s Usable?3xRTT…Enhanced CDMA packet, 2Mb/s raw; 144kb/s Usable? • IDEN(?)
Existing Message Service • e.g. SMS- Implemented by all carriers- Interoperable between carriers- Text Messages- Approximately 160 Character limitation • EMS, MMS- Large data files- spooled voice- photographic Picture quality (needs display!) • but…. • All are Point to Point
GSM- Cell Broadcast • Cell Specific BroadcastsPoint to MultipointShort messages, limited to 15 * 93 Characters (SMS-CB)Up to 64k CB “Channels” • Optional ETSI Standard (1993)Software upgrade to GSM networkNot widely implementedLimited / no commercial payback. • “Cell Broadcast Forum”Standardized handset requirementsUser Opt IN-OUT service selectionSMS-CB can trigger data “pull” ( via WAP )
Geographic Addressability • Return path for 2-Way devices inherentlyrequires network location • Cellular handsets continuously located through“registration” process • Supposition of network geography on networklocation • Geographic resolution depends on cell size,likely poor
Cell Broadcast – Limitations • Cell Resolution is variable, • Network to network, • Place to Place
Selective Area Reception • Assuming………- A broadcast capability, regional or wide area- A population of network assisted GPS handsets… • A Broadcast alert message with…. - “Network assist” GPS data- “Geographic Address” (targeted area)- Emergency alert Message- Enunciation control data- Plus control fields… • Phones located in Geographic address respond…
Handset Function • Special Alert- Display Standardized Message- Streaming Audio File • Probably amenable to commerce • Cellular networks now data “pipes” • Alert / Handset function- Through Network definitions (eg CAB) ?- Through Handset Software ?
Limitations and Liabilities • Some Handsets will miss alerts:- Poor local coverage- Handset in use • Handset use while driving banned some places • Warned user might consult display while driving- Injury may result- Who owns legal liability? • Much preferred to send voiced message- text to voice, or- Streaming audio file
A CAS System • A CAS Server application- Highly reliable, Redundant architecture- Authentication on Clients, direct users • Message Gateway to each carrier • Client population- Generator sites (Police, EMO, Environmental Agencies)- GUI / GIS capability- Overlay of Sensitive Sites- Authentication of Users (generators)
Implementation • Cell Broadcast Alerts- Now available GSM, Coming for CDMA- less than Ideal system could be built- Limited system, Patented • Selective Area Reception- New Message Types- Handset software required- Better System, no patents • Funding- Commercial Applications ?- Subsidies ?
Implementation • Neither Do-able on Present Networks • CAB requires:- CAB Network Implementation (Expensive?)- Public take-up of CAB capable phones- Network development (Geo overlay on Network Topology) • SAR requires:- Extensive lobbying of specifying entities- New system message types (broadcast)- New generation of handsets/handset software • Implementation must be International
Implementation • Government -Industry group to define - Method of selective area access - Broadcast Message spec • CSAAC network requirements • CAS system Design- Server system and Application S/W- Client Application Software • CAS administrative functions- System management, Training, public awareness,
Challenges (1) • 5 year horizon may require mandate • Formation of common intent • Complex service behaviour • Through Handset Software? • Through Network Standards? • Agree on CAS method • Cell location • Selective Area Reception (GPS) • Commercial Applications • Traffic, Geo-referenced Advertising
Thank You Communications Inc Gyles Panther Wi-Sys Communications Inc. 308 Legget Drive, Ottawa, Ontario K2K 1Y6 www.wi-sys.com