NG911: Time to dispatch = 15 years and counting
NG911: Time to dispatch = 15 years and countingHenning
SchulzrinneColumbia University & FCC (with usual
disclaimers)7/23/16TEMU 20161
Emergency communication in the United States
7/23/16TEMU 20162
VoIP emergency communications7/23/16
emergency calldispatchcivic coordinationemergency alertTEMU
20163
90 characters(360 in the future?)wireless emergency
alerts(WEA)
phone & SMS-based (local)AM/FMTVcable
3
Quick history of 911 in the US7/23/16TEMU 20164proposal for
national emergency number by NAFC1957Presidential Commission
recommends single numberfirst 9-1-1 call in Haleyville, AL17% of US
has 9-1-119671968selective call routing trials1970s197650% of US
has 9-1-1198719982001Jan2013Phase I for cellular: deliver tower
& sector to PSAPPhase II for cellular: handset or network
location (carrier req.)NENA NG911 i3 spec.20111999National 911 Act
(Congress)2015Carriers must support text-to-911June2013Text-to-911
bounce-backAug.2016Location test bed50/67%, 150m/80%
(handset)Feb.2017NEAD privacy & security planApr.201750 m for
40% of callsApr.201850 m for 50% of callsAug.2018barometric data
PSAPs
Apr.202070% 50m
Sep 2010:
https://apps.fcc.gov/edocs_public/attachmatch/FCC-10-176A1.pdf
location accuracyDec 2012:
https://www.fcc.gov/document/text-911-further-notice-proposed-rulemakingMay
2013:
https://www.fcc.gov/document/text-911-bounce-back-message-orderJan
2015:
https://apps.fcc.gov/edocs_public/attachmatch/FCC-15-9A1.pdf
text-to-911:
https://apps.fcc.gov/edocs_public/attachmatch/FCC-14-118A1.pdf
(December 31, 2014)
4
What distinguishes US 911 from elsewhere?5,894 PSAPs (in 3,135
U.S. counties)some very large (NYC, LA, Chicago), some
tinytechnical services provided by contractors and system service
providers240 million 9-1-1 calls per year70% cellularEmphasis on
location delivery98.6% of population have some Phase II (July
2016)most carriers use hybrid location (GPS + network-based such
U-TDOA)Funded by variety of add-on 9-1-1 charges on phone bills,
not taxessome of these charges are diverted to other
purposesLimited regulatory authority for national regulator
(FCC)Mostly, iVoIP and cellular providers, not PSAPssome oversight
by state public utilities commission or state 911 officeStrong
professional associations (APCO & NENA), with standard setting
efforts and training7/23/16TEMU 20165
TEMU 2016What do we need for emergency calling?
Identify emergency call
Route call to PSAP
Dispatch first responder
numbers depend on location
at least cell & sector, preferably full geo (say, 100 m)
indoor & outdoor dispatchable locationlocation7/23/16TEMU
20166
E911 NG911
7/23/16TEMU 20167
TEMU 2016E911 vs. NG911
Identify emergency call
Route call to PSAP
Dispatch first responder
112, 911 (in SIM)E911NG911
dial number from ECRFsos URN
ALI + MSAG selective router (SR)based on street address
location ECRFESRP
landline: ALI civic (static)wireless: ALI geo (dyn.)
SIP Geolocation header
7/23/16TEMU 20168
E9-1-1 for wireline
EO Switch
Selective Routeror 911 Tandem
LECnetwork555-1234313 Main StALI100-500 Main Street ESN
1789555-1234 PSAP #1, 313 Main StCAMA or PRIdelivers
ANI(555-1234)CAMA or SS7ANI: 555-1234 313 Main555-1234 PSAP #1PSAP
#1verify addressvalidityprovisionedupdatesprivatedata
linkMSAG7/23/16TEMU 20169
TEMU 2016Different sources for emergency
calls7/23/16SourceLocationChallengesTDM landlinecivic,
staticrapidly fading; equipment obsoleteinterconnected VoIP(OTT or
cable/FTTH)currently, user-configuredor similar to landlineVoIP
(OTT)noneno locationCellulargeo, separate pathlocation
accuracyindoor dispatchable locationTelematics(car, alarms, )mostly
geoadditional dataindoor & outdoor location
TEMU 201610
TEMU 2016US landline phone service11
FCC Voice Telephone Services: Status as of December 31, 2014
7/23/16TEMU 2016
About half of households are wireless-only7/23/16TEMU 201612
Wireless 911Phase I (April 1998)Route all call to the
appropriate PSAP based on call sectorProvide cell/sector location
data to PSAPProvide call back number to PSAPPhase II (October
2001)Phase I + latitude and longitude
67%95%handset50m150mnetwork100m300m
7/23/16TEMU 201613
TEMU 2016Text-to-911 architecture14
Intrado, Text-to-9-1-1 saves Lives, 20137/23/16TEMU 2016
7/23/16TEMU 201615
NG911 architecture (US, Canada)
Brian Rosen, 2012SIP proxyLoSTHELDprivate (shared) IP
network
PIDF
PIDF
also, NG112(Europe)7/23/16TEMU 201616
Emergency Call Routing FunctionQueried using LoST
ProtocolLocation and Service in, URI outExternal ECRF provided by
9-1-1 AuthorityLocation Information ServerStores location against
some kind of keyProvided by Access NetworkUses either DHCP or HELD
to give location to end deviceBorder Control FunctionSecurity
barrier between origination/access networks and ESInetCombination
of firewall and Session Border ControllerEmergency Services Routing
ProxyCall Router for ESInetUses ECRF to get next hop routePolicy
Controlled RoutingLegacy Network GatewayLooks like SR/ALI to legacy
networkRoutes using ECRF to ESInetLegacy PSAP GatewayLooks like
SR/ALI to unupgraded PSAP7/23/16TEMU 201617
Insanity is Doing something 6,200 times and expecting a speedy
result.(Einstein + Heisenberg)
7/23/16TEMU 201618
TEMU 2016US NG911 status2011(27 responses)2013(39
responses)Statewide NG911 plan915Concept of operations312Request
for proposals released13Contracts13Testing parts, functions and
components at state level9
7/23/16TEMU 201619
What are the causes?Bottom up: small groups of PSAPs get
togetherbuild (have built) their own ESInetDeploy their own ESRP,
ECRF, LNGEach requires educating the late adopters, consultants,
RFP, negotiation with carriers, coordinated funding, Engineered as
one-offsCustom interconnect, equipment, configuration, 600
selective routersCapital investmentBut 911 entities typically
cannot issue bondsNo significant national funding sourcesDiversion
of 911 fees collected by many U.S. statesExpertise uneven (GIS, IP
networks, cybersecurity, )Carrier obligations make PSAPs pay for
legacy services7/23/16TEMU 201620
Alternative network modelsCurrent deployment modelnetwork
islands with SBC moatsone county, one network, one server rack, one
purpose, one decadeSimilar to early academic Internet
Internet2initially custom, then re-use dark fibermembership
model?
Suomenlinna
7/23/16TEMU 201621
Alternative network models
national network(s)
LoST
LIS
VPNs
major network interconnect points:SEA, LAX, SJC, DEN, CHI, BOS,
DC, NYC 7/23/16TEMU 201622
911 apps emerging7/23/16TEMU 201623Offer advanced featuresNotify
family & friendsShare imagesAvoid delays in the carrier PSAPs
system service provider dependency circleChallengesAre 911 calls
delivered to the right PSAP?911 features on handsetsFunding model
consumer pays? PSAP pays?Privacy concerns
https://www.apcointl.org/doc/advocacy/623-the-status-of-9-1-1-apps/file.htmlhttp://appcomm.org/23
Locating emergency callers
7/23/16TEMU 201624
Caller location25Builds on long history of FCC location accuracy
requirementsimplicitly outdoor: 50m (67%)/150m (80%-90%) circles
(1996), with geographic exclusionsdispatchable location or x/y
within 50 m~70% calls are wirelessunknown % indoorresidential
indoor may allow GPSz axis:3 years: uncompensated barometric6
years: 80% of top 25 CMAsopen issues:nomadic iVoIPseparation of
location & call deliveryreliable location w/o power
7/23/16TEMU 2016
25
Overall system architecture
GPS
Accelerometer
Magnetometer
GyroscopeInertial Measurement Unit (IMU)
Activity Manager
Infrastructure Monitor
Analysis ModulesSensor Array
ElevatorModule
EscalatorModule
StairwayModuleData Sampling for DetectionData Sampling for
Analysis
Detected Activity
Anchor Location
InfrastructureUser DeviceBuilding Information
Indoor-outdoor transition
GPS Trace
Building Database Server
Entrance Beacon
Location Beacons
7/23/16TEMU 201626
TEMU 2016Indoor location
NEAD
indoor oroutdoor?7/23/16TEMU 201627
crowdsourced database
commercial Wi-Fi databasebuilding/streetWiFi APfloor, apartment,
office
GPS or GNSSknown location?location = f(observed APs,
barometer)where are you?record common locations?
27
Indoor location challenges7/23/16TEMU
201628AdvantageChallengesPossible approachesGNSSnear-universal in
handsetsno infrastructurefails in dense urban canyonssteel frame
buildingsLong-term: L2C & L1C GPSWi-Finear-universal in
handsetsexisting infrastructureground truth
(room-level)movescrowdsourcingBlueToothuniversal in newer
handsetsmapping beacons to locationmaintenancecrowdsourcingbuild
into infrastructureBarometriccheap to addlimited handset
availabilityindoor air pressureweather compensationmapping
elevation to floorbuilding-level calibrationcombine with
Wi-FiAccelerometer (dead reckoning)near-universal in handsetsno
infrastructureaccuracy & mode detectionmapping elevation to
flooruse in hybrid systems
Using accelerometer to measure floors
Errors when traveling 1-9 floors without stopping using
elevatorErrors when traveling 9 floors making 1-4 stops using
elevator
Landing counting errors in 50 trials of walking 4 floors on
stairwayCDF of errors when traveling 2 floors (7.3m) using
escalatorW. Song, J. Lee, B. Lee, and H. Schulzrinne:Finding 9-1-1
Callers in Tall Buildings
Location services beyond Wi-Fi
7/23/16TEMU 201630
Conclusion7/23/16TEMU 201631US 911: slow & fastscale
advantage + large citiesbut resource-challenged and entrenched
interestscontinuous improvement as technologies become
availableoften, layered on top of existing technology: ALI, SMS,
TTYface more fundamental changes: 911 apps, indoor location
Backup
7/23/16TEMU 201632
E911 location accuracy requirements (9/2010)7/23/16TEMU
201633Handset-basedNetwork-based50
m/67%150m/80-90%100m/67%300m/90%Year 1 Jan. 201260% of counties
covering 70% of popsYear 2 Jan. 201350 m/67% ea. county150m/80% ea.
countyCarriers must provide confidence and uncertainty data on a
per call basis upon PSAP request Year 3 Jan 201470% of counties
covering 80% of pops (can use blended data)60% of counties with 70%
pops (can use blended data) Year 5 Jan 2016100% of counties(can use
blended or handset data) 70% of counties with 80% of pops(can use
blended data)Year 8 Jan 2019150m/90% ea. county85% of counties(can
use blended or handset data) ExclusionsMay exclude 15% of counties
w/forestation(no sunset)May exclude counties where triangulation
not feasible (< 3 sites) sunsets after Year 8
47 CFR 20.18(h)
https://www.law.cornell.edu/cfr/text/47/20.1833
TEMU 2016US voice telephony connections34
FCC Voice Telephone Services: Status as of December 31, 2014
7/23/16TEMU 2016
https://apps.fcc.gov/edocs_public/attachmatch/DOC-338629A1.pdf
null71940.43
