1. Jong Yul Kim, Wonsang Song, and Henning Schulzrinne
NG9-1-1 Prototype Demo
Jong Yul Kim, Wonsang Song,
and Henning Schulzrinne

2. Overview Prototype Architecture and Components
Demonstration of Features
Demo 1 : Location determination
Demo 2 : Call Routing
Demo 3 : Multimedia and Mapping
Demo 4 : Inviting third party
Demo 5: Fully Mute / Partially Mute
Demo 6 : Callback
Demo 7 : Logging
Demo 8 : Queue
Demo 9 : Overload Control

3. Prototype Architecture

4. SIPc, a multi-function SIP UA
Function (caller side)
Identifies and initiates emergency call
Determines location from various sources
Function (calltaker side)
Interfaces with location mapping software
Shows calltaker status, responder list, incident type
Implementation
Tcl/Tk based User Interface and SIP stack
External programs for audio, video, application sharing, stun, etc.

5. Location Information Sources
Function
Provides location information to SIPc
Implementation
GPS : USB device and NMEA 0183 parser
Location Information Server built using Apache, MySQL, and PHP

6. LoST Cluster Function Implementation
Translates (Location, Service) to a PSAP URL and emergency dial string
Verifies civic address
Implementation
PostgreSQL with PostGIS extension as a Database
US county boundary polygons to simulate geo PSAP boundary
Sample MSAG data for civic PSAP boundary
Tomcat + Axis for Web Service
MSAG data is for Texas Harrison County.

7. sipd, a SIP proxy and registrar
Function
Routes call to destination
Resolves SIP URL to a reachable address
Invokes sip-cgi for in-network special services
Implementation
CINEMA (Columbia InterNet Extensible Multimedia Architecture)
sip-cgi is perl-based

8. psapd, a back-to-back SIP UA
Function
Facilitates multi-party conference setup
Distributes incoming call to call takers
Logs call details
Implementation
CINEMA C++ library (libsipapi)
Call distribution logic is written in Tcl

9. psapd handles an incoming call
All signals go through psapd
psapd controls conference instances through MSCML
Media is directed to conference server

10. Conference Server Function Implementation Mixes and records audio
Distributes video
Call Queuing
Interactive Voice Response
Implementation
sipconf from CINEMA
Snowshore IP Media Server from Cantata Technology

11. Location Mapping Software
Function
Plots caller’s location and other information on a local map
Shows nearby responders on map
Implementation
Geolynx Mapping System from GeoComm
Google Maps

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

13. Demo 1 : Location Determination
DHCP
CDP
SkyHook

14. DHCP for Location Mainly for stationary users
We modified ISC’s dhcpd to generate location information
Use MAC address to get location information
DHCP Server or
request
response
DHCPINFORM
[MAC=00:11:20:9d:a0:03]
DHCPACK
[option=0:US:1:NY:2:NEW YORK:
3:NEW YORK:6:AMSTERDAM:19:1214]

15. CDP for Location Mainly for stationary and nomadic users
Cisco Discovery Protocol (Layer2)
Cisco switches broadcast switch/port ID periodically.
A Switch covers a floor, a port leads to a jack in a room
-> room-level accuracy

16. SkyHook for Location Mainly for nomadic, mobile users
Wireless device receives signals from Wi-Fi sites in range
Skyhook compares signals to its database of geographically known locations
Location data is used to direct safety services
Taken from

17. Demo 2 : LoST

18. Demo 3 : Multimedia and Mapping

19. Demo 4 : Inviting third party

20. Demo 5 : Fully / Partially Mute

21. Demo 6 : Callback

22. Demo 7 : Logging

23. Demo 8 : Automatic Call Distribution
Based on availability of call taker
Language-based distribution
Queue
Auto-Response based on time and location of new incoming call

24. Demo 9 : Overflow Control
NOTIFY
SUBSCRIBE
INVITE
REDIRECT
INVITE

25. Demo 9 : Overflow Control
NOTIFY
SUBSCRIBE
INVITE
INVITE

26. Future Work Implement additional Features
Auto-Response based on time and location of incoming call
Video Push to caller (e.g. CPR how-to)
Measuring and reducing latency

27. More Information A VoIP Emergency Services Architecture and Prototype
Matthew Mintz-Habib, Anshuman Rawat, Henning Schulzrinne, and Xiaotao Wu
ICCCN 2005, Oct. 2005
An Enhanced VoIP Emergency Services Prototype
Jong Yul Kim, Wonsang Song, and Henning Schulzrinne
ISCRAM 2006, May 2006
More information available on