Transcript sos small carrier

The Next Generation 9-1-1
Proof-of-Concept System
SIP 2009 (Paris, January 2009)
Talk Outline
• Background
– why is emergency calling difficult for VoIP?
– numbers, call routing, …
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•
•
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High level proof-of-concept architecture
Location configuration
Call routing
Lessons learned
Modes of emergency
communications
emergency call
information
“I-am-alive”
emergency alert
(“inverse 911”)
dispatch
civic coordination
3
Background on 9-1-1
• Established in Feb. 1968
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–
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1970s: selective call routing
late 1990s: 93% of population/96% of area covered by 9-1-1
95% of 9-1-1 is Enhanced 9-1-1
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)
http://www.nena.org/
4
Local Switch
Automatic
Number
Identification
Automatic
Location
Identification
IEEE NY
Collaboration between
local phone providers and
local public safety agencies
5
POTS
What makes
VoIPVoIP
112/911
hard?
PSTN-emulation
end-to-end
VoIP
(landline) phone
number limited to
limited area
landline phone number no phone number or
anywhere in US (cf.
phone number
German 180)
anywhere around the
world
regional carrier
national or continentwide carrier
enterprise “carrier” or
anybody with a peerto-peer device
voice provider = line
provider (~ business
relationship)
voice provider ≠ ISP
voice provider ≠ ISP
national protocols and
call routing
probably North
America + EU
international protocols
and routing
location = line location
mostly residential or
small business
stationary, nomadic,
wireless
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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
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Service URN
• Idea: Identifiers to denote emergency calls
– and other generic (communication) services
• Described in IETF ECRIT RFC 5031
• Emergency service identifiers:
sos
sos.animal-control
sos.fire
sos.gas
sos.marine
sos.mountain
sos.physician
sos.poison
sos.police
General emergency services
Animal control
Fire service
Gas leaks and gas emergencies
Maritime search and rescue
Mountain rescue
Physician referral service
Poison control center
Police, law enforcement
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“EMERGENCY HELP. Anytime, anywhere, any device.”™
National Emergency Number Association (NENA)
IETF ECRIT Working Group
IETF GEOPRIV Working Group
NENA
High level requirements
Use of multimedia
Data delivery and sharing
Recording and incident details
Call taker user interface
Technical standards
Technical standards
IETF ECRIT Working Group
System architecture
IETF GEOPRIV Working Group
Behavior of components
Format of location objects
The NG9-1-1 POC System
The POC system is deployed in 5 real PSAPs and 3 labs across the USA.
PSAP: Public Safety Answering Point (=Emergency call center)
King County, WA
Bozeman, MT
St. Paul, MN
Rochester, NY
Columbia
Univ. Lab
Fort Wayne, IN
BAH Lab
TAMU Lab
POC system is divided into two networks
Emergency Services Network (ESN)
PSAP A
9-1-1
Location-to-Service
Translation (LoST)
Server
PSAP SIP
Proxy
.
.
.
Emergency Services
Routing Proxy (ESRP)
Call Distributor
Call Takers
SIP-based network
of PSAPs
SIP Back-to-back
User Agent
managed by the emergency authorities
.
Network
used by emergency
caller
to
ask
for .help
Public
Safety
Answering
Points (PSAP)
Emergency
Services
Network
(ESN)
.
PSAP Z
Examples: PSTN, Cellular, Residential VoIP
Access Network
Role
1. Determine location of caller
2. Route call to ESN
Conference Server
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
①
②
Why is location important?
• Send help to the site of emergency
• Route call to the correct destination
How do I send my location?
•Sent along with SIP INVITE
•Formatted as PIDF-LO XML object
GPS
LLDP-MED
DHCP
Cell Tower
Manual Entry
Skyhook Wireless
Location determination options
Method
CDP or LLDPMED
DHCP
HELD
GPS
manual entry
Layer
L2
L3
L7 (HTTP)
-
user
advantages
• simple 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
problems
may 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
Use
Ethernet LANs
Enterprise
LANs
Some ISPs
DSL, cable
mobile devices
fall back
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LoST
• LoST = Location-to-Service Translation
• LoST lets you find a PSAP
• RFC 5222 from IETF ECRIT WG
Caller’s location
+
Service identifier
(urn:service:sos)
Service provider
(PSAP URL)
+
Emergency Dial String
LoST: Location-to-URL Mapping
VSP1
cluster serving VSP1
cluster
serves VSP2
123 Broad Ave
Leonia
Bergen County
NJ US
replicate
root information
LoST
sip:[email protected]
NJ
US
root
NY
US
nodes
search
referral
Bergen County
NJ US
Leonia
NJ US
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LoST Architecture
G
tree guide
G
G
G
T1: .us
G
broadcast (gossip)
T2: .de
resolver
seeker
313 Westview
Leonia, NJ US
T2
T1
(.us)
(.de)
T3
(.dk)
Leonia, NJ  sip:[email protected]
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LoST: Query example
• Uses HTTP or HTTPS
<findService xmlns="urn:…:lost1”
recursive="true" serviceBoundary="value">
<location profile="basic-civic">
<civicAddress>
<country>Germany</country>
<A1>Bavaria</A1>
<A3>Munich</A3>
<A6>Neu Perlach</A6>
<HNO>96</HNO>
</civicAddress>
</location>
<service>urn:service:sos.police</service>
</findService>
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LoST “Find Service” response/warning example
<findServiceResponse xmlns="urn:ietf:params:xml:ns:lost1">
<mapping expires=“1990-12-31T23:59:60Z” lastUpdated=“2006-11-01T01:00:00Z”>
<displayName xml:lang="de">München Polizei-Abteilung</displayName>
<service>urn:service:sos.police</service>
<serviceBoundary profile=”civic”>
<civicAddress xmlns="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr">
<country>Germany</country>
<A1>Bavaria</A1><A3>Munich</A3><PC>81675</PC>
</civicAddress>
</serviceBoundary>
<uri>sip:[email protected]</uri>
<serviceNumber>110</serviceNumber>
</mapping>
<path>
<via source=“lost:esgw.uber-110.de.example”/>
<via source=“lost:polizei.munchen.de.example”>
</path>
</findServiceResponse>
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Emergency Services Network (ESN)
Cellular
PSAP A
LoST
9
-1-1
9-199-1-1
Location-to-Service
Translation (LoST)
Server
Emergency Services
Routing Proxy (ESRP)
SIP
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
.
. Points (PSAP)
Public Safety Answering
.
PSAP Z
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
RTP
Conference Server
Access Network
Emergency Services Network (ESN)
SMS
PSAP A
LoST
9
-1-1
9-199-1-1
Location-to-Service
Translation (LoST)
Server
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
“Bank robbery!”
Emergency Services
Routing Proxy (ESRP)
SIP
.
. Points (PSAP)
Public Safety Answering
.
PSAP Z
S
Conference Server
Access Network
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
Emergency Services Network (ESN)
Telematics
PSAP A
LoST
9
-1-1
9-199-1-1
Location-to-Service
Translation (LoST)
Server
Emergency Services
Routing Proxy (ESRP)
SIP
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
.
. Points (PSAP)
Public Safety Answering
.
PSAP Z
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
RTP
Conference Server
Access Network
Crash Data
Emergency Services Network (ESN)
All Busy
PSAP A
LoST
9
-1-1
9-199-1-1
Location-to-Service
Translation (LoST)
Server
Emergency Services
Routing Proxy (ESRP)
SIP
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
.
. Points (PSAP)
Public Safety Answering
.
PSAP Z
PSAP SIP
Proxy
.
.
.
Call Distributor
SIP Back-to-back
User Agent
Call Takers
RTP
“All call takers are busy…”
Conference Server
Access Network
Calltaker screen
•
•
Columbia SIPc as SIP UA
Mapping software to display caller’s location
– Geolynx
– Google Maps
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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
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Challenges for NG911
• Technically, much simpler than E911 Phase II
–
–
–
–
hopefully, cheaper, too
but security challenges: location and identity verification
co-existence between E911 and NG911
integrating external data (e.g., OnStar) -- from silo to NG911
SOA
• Logistical challenges
– deployment of new infrastructure
• location and LoST servers
• Legal and regulatory challenges
– will ISPs give out location information to VSPs or customers?
– liability for misrouted calls?
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Final Comments
• We are beginning to understand what an
emergency response system should look like
• Lots of interesting network problems in
emergency communication systems
– Geographic Location of network devices
– “Call setup time (dialing of last digit to ring at the
PSAP), under expected peak load shall be less than 2
seconds.”
– Reliable communications in large scale disasters