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911 Background. Traditional 911 ~6,000 PSAPs in the US Selective routers route calls to correct PSAP Operated by carriers Relies on DB of fixed subscriber addresses Calling number (ANI) “pulsed” over CAMA trunk 1970s technology Number resolved to address (ALI) through geo-DB (MSAG)
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911 Background • Traditional 911 • ~6,000 PSAPs in the US • Selective routers route calls to correct PSAP • Operated by carriers • Relies on DB of fixed subscriber addresses • Calling number (ANI) “pulsed” over CAMA trunk • 1970s technology • Number resolved to address (ALI) through geo-DB (MSAG) • PSAPs under pressure for years to support cellular E-911 • Internet 911 • 911 has been a thorn in the side of VoIP • FCC 911 mandate
What Makes NG911 Hard • Mobility • ISP≠VSP • Not just “9-1-1” • Closed, proprietary legacy systems ISP=T-Mobile PSAP emergency = “1-1-2” German Tourist Taiwanese VSP Rhode Island Germany
NG911 • NG911 Project • Goal: deploy proof-of-concept IP-enabled PSAPs • $1.3 million dollar, two-year project funded by NTIA, the States of Texas and Virginia 911 offices, Cisco and Nortel • National Emergency Numbering Association (NENA) participation • Goal of NG911 is, not only to solve VoIP 911, but to do better! • Higher resilience • Faster call setup • Testability • Internationality • Multimedia support • Open standards and COTS • Cheaper
Components of Emergency Calling Now Transition All IP fixed Establish caller location Client or proxy learns (e.g. GPS, CDP, LLDP-MED, DHCP) fixed orinfrastructure discovers Contact well-known emergency number or ID 112 911 112 911 dial 112, 911 urn:service:sos Route call to location-appropriate PSAP selective router VPC DNS, LUMP number location (ALI) in-band key location in-band Deliver precise location to PSAP for dispatch NENA I2 NENA I3 This slide adapted from a slide of Henning Schulzrinne (Columbia University)
Sample NG911 Call-flow 1 ISP 5 <location> (e.g. via DHCP) INVITE sip:psap@prov.state.ri.us To: urn:service:sos <location> mapping PSAP 4 2 1-1-2 3 INVITE urn:service:sos To: urn:service:sos <location> 6 Taiwanese VSP Rhode Island
PSAP Interface This slide complements of Henning Schulzrinne (Columbia University)
Bryan, TX PSAP NG911Workstation
For More Information • ECRIT (Emergency Contact Resolution with Internet Technologies) WG • http://www.ietf.org/html.charters/ecrit-charter.html • Standardizing: • location conveyance (with SIPPING & GEOPRIV) • emergency call identification • mapping geo and civic caller locations to PSAP • discovery of local and visited emergency dial string • NG911 Project • http://ng911.tamu.edu/