Next-Generation Emergency Calling (NG911) Henning Schulzrinne Dept. of Computer Science, Columbia University, New York (with Jong Yul Kim, Wonsang Song, Anshuman Rawat, Matthew Mintz-Habib, Amrita Rajagopal and Xiaotao Wu; LoST is joint work with Hannes Tschofenig, Andrew Newton and Ted Hardie) SIP Workshop April 25, 2008

April Outline Emergency calling –the challenge of two transitions: mobility and VoIP –Emergency alerts Emergency alerting –beyond siren replacement Emergency coordination –going beyond ad hoc networks emergency call coordination alert

April Modes of emergency communications emergency call civic coordination emergency alert (“inverse 911”) dispatch information “I-am-alive”

April Background on Established in Feb –1970s: selective call routing –late 1990s: 93% of population/96% of area covered by –95% of is Enhanced –US and Canada Roughly 200 mio. calls a year (6 calls/second) –1/3 wireless 6146 PSAPs in 3135 counties –most are small (2-6 call takers) –83.1% of population have some Phase II (April 2007) “12-15 million households will be using VoIP as either primary or secondary line by end of 2008” (NENA)

April Local Switch Automatic Number Identification Automatic Location Identification Collaboration between local phone providers and local public safety agencies

April Why is this a hard problem? More than just installing software and buying new PCs –mapping (GIS systems can’t use Google Maps) –training Decentralized system –6000+ PSAPs –estimated cost of upgrade: $340m (=> $57,000/PSAP) 233 million US mobile phone subscribers Cost-plus ILEC MSAG –the MSAG update protocol: fax –no incentive to upgrade –no incentive to cooperate with CLECs and VSPs –unclear ownership of database Issues of control and “turf” –consolidation efficiency vs. local knowledge –funding: state vs. county vs. town (volunteer fire department)

April What makes VoIP 112/911 hard? POTSPSTN-emulation VoIPend-to-end VoIP (landline) phone number limited to limited area landline phone number anywhere in US (cf. German 180) no phone number or phone number anywhere around the world regional carriernational or continent- wide carrier enterprise “carrier” or anybody with a peer- to-peer device voice provider = line provider (~ business relationship) voice provider ≠ ISP national protocols and call routing probably North America + EU international protocols and routing location = line locationmostly residential or small business stationary, nomadic, wireless

April More than pain… Multimedia from the caller –video capture from cell phones –video for sign language –text messaging and real-time text for the deaf Data delivery –caller data: floor plan, hazmat data, medical alerts –measurement data input: automobile crash data, EKGs, … Delivering video to the caller –e.g., CPR training Load balancing and redundancy –currently only limited secondary PSAP –VoIP can transfer overload calls anywhere Location delivery –carry location with forwarded and transferred calls –multiple location objects (civic + geo)

April Phase 1Phase 2Phase 3 Phase 4 Four Phases of Emergency Calls

April Emergency numbers Each country and region has their own –subject to change Want to enable –traveler to use familiar home number –good samaritan to pick up cell phone Some 3/4-digit numbers are used for non-emergency purposes (e.g., directory assistance) Emergency number

April Service URN Idea: Identifiers to denote emergency calls –and other generic (communication) services Described in IETF ECRIT draft draft-ietf-ecrit-service-urn Emergency service identifiers: sos General emergency services sos.animal-control Animal control sos.fire Fire service sos.gas Gas leaks and gas emergencies sos.marineMaritime search and rescue sos.mountainMountain rescue sos.physicianPhysician referral service sos.poisonPoison control center sos.policePolice, law enforcement

April Services under discussion “211” (social service referral), “311” (non-emergency government services) Emergency services (first responders) –used by PSAP, not civilians –e.g., urn:service:es:police Non-emergency commercial services –urn:service:restaurant.italian –urn:service:transportation.taxi

April Location, location, location,... Voice Service Provider (VSP) sees emergency call but does not know caller location ISP/IAP knows user location but does not handle call

April Location determination options MethodCDP or LLDP- MED DHCPHELDGPSmanual entry LayerL2L3L7 (HTTP)-user advantagessimple to implement built into switch direct port/room mapping simple to implement network locality traverses NATs can be operated by L2 provider accurate mobile devices no carrier cooperation no infrastructure changes no carrier cooperation problemsmay be hard to automate for large enterprises mapping MAC address to location? mapping IP address to switch port? indoor coverage acquisition time fails for mobile devices unreliable for nomadic UseEthernet LANsEnterprise LANs Some ISPs DSL, cablemobile devicesfall back

April Components of NG911 system Location determination Call identification --> service URNs Call routing --> LoST PSAP functionality –IVR, logging, multimedia conferencing, … LoST (public) LoST (private) Internet ESN (county, state, …) PSAP

April UA recognition & UA resolution INVITE urn:service:sos To: urn:service:sos Route: (dial string) mapping INVITE urn:service:sos To: urn:service:sos Route: leonianj.gov mapping may recurse location information DHCP LLDP-MED identification TBD

April UA recognition & proxy resolution mapping INVITE urn:service:sos To: urn:service:sos INVITE urn:service:sos To: urn:service:sos Route: (outbound proxy) provider.com

April UA recognition & proxy resolution (proxy location determination) mapping INVITE urn:service:sos To: urn:service:sos INVITE To: urn:service:sos Geolocation: provider.com

April Proxy recognition & proxy resolution mapping INVITE To: INVITE urn:service:sos To: Geolocation: Route: provider.com

LoST: A Protocol for Mapping Geographic Locations to Public Safety Answering Points Henning Schulzrinne, Hannes Tschofenig, Andrew Newton, Ted Hardie

April Problem: Finding the correct PSAP Which PSAP should the e-call go to? –Usually to the PSAP that serves the geographic area –Sometimes to a backup PSAP –If no location, then ‘default’ PSAP –solved by LoST

April LoST functionality Mapping of location to parameters (e.g., URL) Civic as well as geospatial queries –civic address validation Recursive and iterative resolution Pre-querying and caching for efficiency and robustness –query ahead of emergency call (e.g., at boot time for stationary devices) –no re-querying while moving Fully distributed and hierarchical deployment –can be split by any geographic or civic boundary –same civic region can span multiple LoST servers Indicates errors in civic location data  debugging –but provides best-effort resolution Supports overlapping service regions –e.g., contested regions (Kashmir, Palestine, Taiwan,...)

April LoST: Location-to-URL Mapping cluster serves VSP 2 NY US NJ US Bergen County NJ US 123 Broad Ave Leonia Bergen County NJ US cluster serving VSP 1 replicate root information search referral root nodes Leonia NJ US VSP 1 LoST

April LoST Architecture T1 (.us) T2 (.de) T3 (.dk) G G G G G broadcast (gossip) T1:.us T2:.de resolver seeker 313 Westview Leonia, NJ US Leonia, NJ  tree guide

April LoST Properties Minimizes round trips: –caching individual mappings –returns coverage regions (“hinting”) civic (“all of C=US, A1=NY”) or geo (polygon) Facilitates reuse of Transport Layer Security (TLS) Returns emergency service numbers for a region Query for supported Service URN types

April LoST: Query example Uses HTTP or HTTPS <findService xmlns="urn:…:lost1” recursive="true" serviceBoundary="value" > Germany Bavaria Munich Neu Perlach 96 urn:service:sos.police

April LoST “Find Service” response/warning example München Polizei-Abteilung urn:service:sos.police Germany Bavaria Munich

April Validation Determine if civic location is (partially) valid Returns XML tag names of components: –validated and used for mapping –no attempt to validate (and not used) e.g., house number –known to be invalid Return (default) PSAP based on validated elements May return list of guesses for correct addresses, if requested country A1 A3 A6 PC

April Advanced LoST functionality Get list of (emergency) services supported –by server –for a region Obtain service regions –identified by globally-unique tag urn:service:sos urn:service:sos.ambulance urn:service:sos.animal-control

April INVITE urn:service:sos SIP/2.0 To: urn:service:sos Call-ID: Via: SIP/2.0/TCP :4064;rport Content-Type: multipart/mixed; boundary From: Contact: CSeq: 1 INVITE Content-Length: =_ZGY1NTFlZDJkMDkxY2FkMTIxMWI2MzIzNjE1M2U0OTY= MIME-Version: 1.0 content-Type: application/sdp Content-Transfer-Encoding: 8bit v=0 o=eddie IN IP s=SIPC Call c=IN IP t=0 0 m=audio RTP/AVP 0 3 m=video RTP 31 SDP header fields request line =_ZGY1NTFlZDJkMDkxY2FkMTIxMWI2MzIzNjE1M2U0OTY= MIME-Version: 1.0 Content-Type: application/pidf+xml Content-Transfer-Encoding: 8bit <presence xmlns="urn:ietf:params:xml:ns:pidf" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:cl=" urn:ietf:params:xml:ns:pidf:geopriv10:civilLoc" xmlns:gml="urn:opengis:specification:gml:schema-xsd:feature:v3.0" us ny new york amsterdam 1214 Manual T15:57:34-04: =_ZGY1NTFlZDJkMDkxY2FkMTIxMWI2MzIzNjE1M2U0OTY=-- PIDF-LO SIP message for Location Info.

April Using LoST for non-emergency services Emergency services: “who serves location X” –one answer desired Non-emergency services: “what services are within radius R of location X” –restaurants, banks, ATMs, hospitals Can use LoST with minor extensions: –shapes allow queries like “show restaurants within Prague city limits” (polygon) or “within 5 miles of where I am” (circle) –restrict number of responses –allow multiple responses

April Current activities IETF ECRIT working group –finishing LoST, architecture, synchronization NENA –architecture –transition documents –web services for queries DOT –NG911 project with BAH, Columbia & TAMU as sub-contractor –building proof-of-concept, based on earlier NTIA work –“National architecture for NG9-1-1 system” & “Transition plan for NG implementation” Lots of other activities –e.g., semi-annual Emergency Services Coordination Workshop

April NG9-1-1 Prototype Architecture RoutingLocation PSTN

April LoST Cluster SIP proxy call taker SOS caller (1)Location Location + Service Identifier (2) INVITE PSAP URL To: urn:service:sos (5) INVITE PSAP URL To: urn:service:sos (6)(4) dial emergency dial- string or push emergency button Emergency Call Flow (3) PSAP URL + emergency dial-string INVITE call taker From: caller (7)(7) Media Stream

April Calltaker screen Columbia SIPc as SIP UA Mapping software to display caller’s location –Geolynx –Google Maps

April Call logs and recorded sessions

April NG911 trial: Lessons learned Tested NG911 prototype in 3 PSAPs in TX and VA Surprise: PSAP is really a conferencing system –LanguageLine, first responders, … Surprise: no uniform incident description –every jurisdiction uses their own variation and level of detail What is desirable behavior –rather than current behavior –e.g., for transfer, overflow Need to integrate call taker management –presence (availability) –a specialized call center Special requirements: partial mute –not typically supported on conference servers

April Conclusion Need for loosely-coupled suite of tools for emergency coordination –connecting rather than stovepipe systems –narrow interfaces rather than global master architecture NG911 as opportunity to update emergency calling –robustness –features (multimedia, connectivity) –COTS Need for large-scale experiments, not yet another ad- hoc network paper –cooperation with non-technical users

April More information A VoIP Emergency Services Architecture and Prototype –M. Mintz-Habib, A. Rawat, H. Schulzrinne, and X. Wu, ICCCN 2005, Oct An Enhanced VoIP Emergency Services Prototype –Jong Yul Kim, Wonsang Song, and Henning Schulzrinne, ISCRAM 2006, May 2006 Providing emergency services in Internet telephony –H. Schulzrinne & K. Arabshian, IEEE Internet Computing, May/June 2002 Requirements for Emergency Context Resolution with Internet Technologies, draft-ietf-ecrit- requirements Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Option for Civic Addresses Configuration Information, RFC 4776 Dynamic Host Configuration Protocol Option for Coordinate-based Location Configuration Information, RFC 3825 A Presence-based GEOPRIV Location Object Format, RFC 4119 A Uniform Resource Name (URN) for Services, draft-ietf-ecrit-service-urn LoST: A Location-to-Service Translation Protocol, draft-ietf-ecrit-lost Best current practices for third party call control (3pcc) in the session initiation protocol (SIP), RFC 3725 GETS: LoST server at NG911 project information at and DOT 911 project DOT 911 project