Upload
makelina-justin
View
47
Download
3
Tags:
Embed Size (px)
DESCRIPTION
A prototype i3 VoIP PSAP implementation. Henning Schulzrinne, Anshuman Rawat, Matthew Mintz-Habib, Xiaotao Wu and Ron Shacham Dept. of Computer Science Columbia University Walt Magnussen, Willis Marti, Patti Urbina Chris Norton, Clark Yang, Karthik Kannan - PowerPoint PPT Presentation
Citation preview
A prototype i3 VoIP PSAP implementation
Henning Schulzrinne, Anshuman Rawat, Matthew Mintz-Habib, Xiaotao Wu and Ron Shacham
Dept. of Computer ScienceColumbia University
Walt Magnussen, Willis Marti, Patti UrbinaChris Norton, Clark Yang, Karthik KannanInternet2 Technology Evaluation Center
Texas A&M University
NENA-VON VoIPCIFSanta Clara, CADecember 2004
Overview
A quick review of I3 assumptions Goals of project Prototype architecture and experiences Scaling and robustness Next steps
Our I3 assumptions
VoIP (SIP) capable end systems SIP-capable PSAP Location inserted by origin
outbound proxy originating device (e.g., via DHCP) either geospatial or civic location
Goals of prototype
Provide a platform for quick experimentation Determine easy vs. hard parts of problem Experiment with redundancy and robustness Use off-the-shelf components where possible Modes
Phase II wireless (based on ALI lookup) I3 VoIP end-to-end, with in-band location
information
Components
sipd SIP proxy server
database-backed DNS server
SIP phone
web server
SQL database for call routing
sipc SIP user agent
geo-coding, PSAP boundaries
GIS software for call location plotting
No endorsement implied – other components likely will work as well
* gray features in progress.
Prototype
911112
sip:sos@domainw/location or w/out location
geo location
POTS/Wireless Network
IP Network
911
IP Gateway
sip:sos@domainwithout location
Envinsa Server
sip:psap@domainwith location
location
GeoLynx Display
ALI ServerDHCP Server
DNS Server**
DHCP InformMAC Address
Location Info
TCP Socket Telephone Number
PSAP Info
HTTP SOAPLatitude/Longitude
Location Info
VerifiedLocation Info
civil location**
Ft. Wayne, IN: August 17, 2004
Demo prototype
911112
sip:sos@domainwith location
geo location
POTS/Wireless Network
IP Network
911
IP Gateway
sip:sos@domainwithout location
ALI Server Envinsa Server
TCP SocketTelephone Number
LocationInfo
PSAPInfo HTTP SOAP
Latitude/Longitude
sip:psap@domainwith location
location
GeoLynx Display
Call routing
PSAP lookup depends on location type: DNS for civic locations Mapinfo Envinsa for geo location
Detail: I3 - DNS-based resolution
151.algonquin-dr.addison.vt.us.sos-arpa.net
Perl sip-cgi script
DNS NAPTR:addison.vt.usalgonquin-dr.addison.vt.us…
psap.state.vt.gov
psap.state.vt.gov
proprietaryTCP-basedprotocol
DHCP INFORM
SIP w/locationMAC loc
SIPc client receives calls GeoLynx software displays caller location
Call taker setup
sipc receives call
GeoLynx receives commands and displays location.Caller location displayed on map.Caller information displayed in GUI.GeoLynx listens for commands from SIPc…
GeoLynx displays location
Demo Ft. Wayne, IN (August 17, 2004)
Using IP phones for voice
XML displaywith HTTP retrieval
XML displayshows caller location
redundant sipd’s
Apacheweb server
Emergency call conferencing
INVITE
3rd partycall control
INVITE
INVITE
REFER
REFER
REFER
Conferenceserver
PSAP
Recorder
Firedepartment
HospitalPSAP brings all related parties into a conference call
INVITE
media info
INVITEmedia info
Caller
INVITE
Scaling
NENA: “estimated 200 million calls to 9-1-1 in the U.S. each year”
approximately 6.3 calls/second if 3 minute call, about 1,200 concurrent calls
typical SIP proxy server (e.g., sipd) on 1 GHz PC can handle about 400 call arrivals/second
thus, unlikely to be server-bound
Next steps for our prototype
Custom user interface for call taker Add voice recording and conferencing
using our software conference server “Data mining”
collect and display statistical data about calls Integration of police/fire/EMS
direct transmission of call-related data via simple IM application requires only Internet access
Difficulties
Difficult to get good test environment access to PDE IP access to ALI (often, jury-rigged telnet
interfaces) access to MSAG and ALI data “friendly” PSAPs one option
but open, network-accessible test lab would be better longer-term: may need “plug fests”
see SIPit effort – vendors collaborating in friendly, non-public interop test efforts rapid elimination of protocol and implementation problems
Conclusion
A first prototype of I3 PSAP integrates Phase II wireless call delivery
Shown that it is possible to integrate existing GIS applications with I3
Based on COTS technology, with modest modifications
Additional operational support in progress
NTIA VoIP i3 PSAP Project
Partners Texas A&M University Columbia University (Dr. Henning Schulzrinne co-PI) The University of Virginia National Emergency Number Association (NENA) The State of Texas Commission on State Emergency
Communications (CSEC) The State of Virginia Division of Public Safety Communications of
the Virginia Information Technologies Agency (VITA). Internet 2 Brazos County Texas E911 District City of College Station Texas Cisco Nortel
Project Goals & Duration
To build and install in an operational PSAP an i3 PSAP prototype system
Provide functional comparison to existing i2 systems
Provide VoIP E911 workshops designed to expand Internet based 911 services awareness
Project to begin on 1 October, 2004 and conclude on 31 September, 2006
Project Responsibilities Columbia University – development of I3
components. TAMU ITEC – I3 field trial and coordination
with PSAP entities.
Cisco and Nortel – Support I2 installations
Thank you – Now for Questions Contact info –
Walt Magnussen [email protected] Ph 979-845-5588
Henning Schulzrinne [email protected] Ph 212-939-7005