This edition first published 2013
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Library of Congress Cataloging-in-Publication Data:

Tschofenig, Hannes.
Internet protocol-based emergency services / Hannes Tschofenig.
pages cm
Includes bibliographical references and index.
ISBN 978-0-470-68976-9 (cloth)
1. Emergency communication systems. 2. Computer network protocols. 3. Internet. 4. Public safety
radio service. I. Title.
TK6570.P8S38 2014
004.67′8–dc23

2013005450

A catalogue record for this book is available from the British Library.

ISBN: 978-0-470-68976-9

To my wife Verena and my daughter Elena. Verena encouraged
me to work on this project and motivated me when I got stuck
due to all my other obligations.

Hannes Tschofenig

List of Figures

1.1   IETF 61 ECRIT BOF: Decision to form a Working Group

1.2   Communication architecture overview

2.1   Uncertainty

2.2   DHCPv6 GeoLoc option format

2.3   DHCPv4 GeoLoc option format

2.4   GeoRSS information model

2.5   LIS location types

2.6   DHCPv4 access domain name encoding for “example.com”

2.7   DHCPv6 Access domain name encoding for “example.com”

2.8   DNS LIS U-NAPTR example

2.9   Residential broadband network topology

2.10   HTTP location request

2.11   Location request with locationType

2.12   Location request using “exact” attribute

2.13   Location request using “responseTime” attribute

2.14   Location request using “responseTime="emergencyRouting"” attribute

2.15   Location response

2.16   Location URI set in location response

2.17   HELD error example

2.18   Device identity extensions structure

2.19   Complex device identity

2.20   A tel URI example

2.21   Location request with identity extension

2.22   Required identifiers example

2.23   HELD measurement container

2.24   Measurements in Location Request

2.25   HELD dereference context diagram

2.26   HELD policy URI request and response

2.27   Policy URI Usage

2.28   Device capabilities signaling diagram

2.29   Capability indication example

2.30   Capabilities agreement

2.31   Capability invoation

2.32   SET Initiated procedures for Proxy Mode and Non-Proxy Mode

2.33   IMS emergency services call flow

2.34   Network Initiated procedures for Proxy Mode

2.35   Network Initiated procedures for Non-Proxy Mode

2.36   Synchronous responses for Standard and Emergency Location Immediate Services

2.37   Asynchronous reporting for Standard and Emergency Location Immediate Services

2.38   Standard and Emergency Location Reporting Service

2.39   Subscription to Location Notifications

2.40   Location services architecture in 3GPPTM networks

2.41   Positioning network elements for UTRAN access networks

2.42   Positioning network elements for E-UTRAN access networks

3.1   The i2 functional architecture diagram

3.2   Basic call routing of VoIP emergency calls in NENA i2

3.3   Call routing using SIP Redirect Server in NENA i2

3.4   Call routing using an SIP Routing Proxy in NENA i2

3.5   High-level functionality of Location to Service Translation (LoST)

3.6   Main components involved in an emergency call

3.7   Trees and forest guides in the LoST mapping architecture

3.8   Example query/response in the LoST mapping architecture

3.9   Mapping element

3.10   Emergency services architecture with legacy endpoints

3.11   Business entities in WiMAX

3.12   Mobile WiMAX NRM

3.13   Network reference architecture for emergency services in WiMAX

3.14   Relations between stackholders in WiMAX emergency calls

3.15   Emergency network entry

3.16   WiMAX Location Support

3.17   Network-based location retrieval after handoff via anchor AAA client

3.18   User A calls User C while roaming to VPLMN B

3.19   CS emergency call while roaming to VPLMN

3.20   CS emergency call flow example

3.21   IMS: call between roaming subscribers

3.22   IMS emergency registration and call path

3.23   IMS emergency registration flow

3.24   IMS emergency call flow

4.1   SOS-NTP interconnection point to the PSAP

4.2   Generic emergency call flow

4.3   Routing overview

4.4   Residential user emergency call scenario

4.5   Emergency call scenario from a company running its own voice service

4.6   Emergency call scenarios for a multinational company running its own voice service

4.7   Example of PSTN breakout in Denmark, forwarding the emergency call over the PSTN to Sweden

4.8   Two emergency call scenarios for a telecommunication provider running a voice service for residential Users

4.9   Emergency call scenario where SIP trunk provider only forwards the call

4.10   Emergency call scenario where SIP trunk provider adds information

4.11   Today’s emergency services architecture in the United Kingdom

4.12   Proposed UK VoIP transition emergency services architecture

4.13   Example VoIP Basic 9-1-1 interim solution

4.14   The Canadian i2 functional model

4.15   Schematic of the IN911 network topology

5.1   Communication model overview

6.1   Total Conversation relay support

8.1   Total Conversation concept: user interface example

8.2   All users in the chain have access to Total Conversation facilities

8.3   Functional blocks of the Monster IMS Client

8.4   Algorithm for placing incoming calls in the virtual queue

8.5   US DOT NG9-1-1 POC system architecture

8.6   SMS server

8.7   Screenshot of call-taker SIPc

8.8   Call origination networks

8.9   Basic emergency call flow

8.10   NG9-1-1 testing phases

List of Tables

2.1   Examples of civic address labels

2.2   HELD error codes

2.3   HELD identity extensions

2.4   HELD measurement specification access measurement types

2.5   MLP services

2.6   Notes to Figure 2.40

2.7   General-purpose 3GPP network entities

2.8   Network entities dedicated to location services

2.9   Network entities for location and emergency services in IMS

2.10   Interfaces, and reference points

3.1   3GPP emergency services categories

3.2   Notes to Figure 3.20

3.3   Notes to Figure 3.24

8.1   PEACE Consortium

8.2   Call origination equipment list

8.3   NG9-1-1 network equipment list

8.4   PSAP equipment list

8.5   Proof of Concept findings

List of Contributors

Bernard Aboba, Skype

Anand Akundi, Telcordia

Carla Anderson, e-Copernicus

Gabor Bajko, Nokia

Ray Bellis, Nominet

Chantal Bonardi, European Telecommunications Standards Institute (ETSI)

Margit Brandl, Nokia Siemens Networks

Guy Caron, Text written in personal capacity; works for Canadian telecommunication operator

John Chiaramonte, Booz Allen Hamilton

Martin Dawson, CommScope

John Elwell, Siemens Enterprise

Gunnar Hellström, Omnitor

Jean-Pierre Henninot, Ministère de l’Economie de l’Industrie et de l’Emploi (MEIE)

Hannu Hietalahti, Nokia

Roger Hixson, National Emergency Number Association (NENA)

Jan Kåll, Nokia Siemens Networks

Jong Yul Kim, Columbia University

Dirk Kröselberg, Siemens

Jim Kyle, University of Bristol

Samuel Laurinkari, Nokia Siemens Networks

Christopher Libertelli, Skype

Gary Machado, European Emergency Number Association (EENA)

John Martin, AuPix Limited

Yacine Rebahi, Fraunhofer FOKUS

Carl Reed, Open Geospatial Consortium (OGC)

Brian Rosen, NeuStar

Jakob Schlyter, Kirei AB

Byron Smith, L.R. Kimball

Wonsang Song, Columbia University

Martin Thomson, Skype

Khiem Tran, CommScope

Gordon Vanauken, L.R. Kimball

Ed Wells, Text written on behalf of CLDXF Work Group (WG), Data Structures Subcommittee, Core Services Committee, National Emergency Number Association (NENA)

James Winterbottom, CommScope

Preface

The Internet has changed our society in astonishing ways during the past 20 years. It has enabled companies as well as individuals to communicate information easily to a worldwide audience. It has also influenced the way we interact with each other.

The topic of this book is a result of this change: emergency services is a feature of the telecommunication system and is therefore tightly bound to the evolution of the underlying communication infrastructure.

As communication moves to the Internet Protocol (IP)-based infrastructure, there is the question of how emergency services should be offered in this new communication environment. From a technology point of view, it has the potential to offer more functionality at a lower cost. This book describes the completed efforts as well as ongoing developments to make IP-based communication systems offer emergency services functionality.

Readers

This book assumes that the reader has a minimum level of familiarity with how the Internet and telecommunication infrastructure works. In particular, some understanding of the Internet Protocol and the Session Initiation Protocol, which is at the heart of the communication architecture, is assumed. Interested readers will find many resources on the Web and in various referenced books and specifications for further reading.

This book is directed toward the following groups:

Research Community. For researchers and students, this book provides a quick entry to the large world of emergency services. Even though the content of the book does not focus on identifying new research areas, a student will be able to capture the state of the art, find two research/pilot projects described in this book, discover information on ongoing work and the organizations and communities where this work is taking place, and see where gaps still exist at the time of writing.

Standards Developing Experts. A standards expert working in one organization is, in our experience, very often unfamiliar with the work done in other standards developing organizations. A lack of understanding of the regulatory environment, ongoing deployment efforts, or broader organizational landscape is not uncommon either. As such, this book will help anyone working on standards to better understand the multiple facets of this topic.

Product Architects. Those who must develop new products or update their existing products to support regulatory mandates or to support new services for their customers face the difficult decision about what standards to read, support, and implement. This book covers the broad range of standards in the emergency services space and answers many high-level questions. This book, however, does not provide the details for implementers to start coding. The referenced specifications contain the authoritative text, though, with much greater detail and valuable examples.

Regulatory Community. Regulators from all over the world are observing the evolution of telecommunication, which is a heavily regulated area, and are wondering about how the desire of companies and their customers for global communication over the Internet is changing their role. This book provides them with an overview of the developments worldwide in a high-level form. While parts of the book go into technological details, we provide an overview to every chapter to allow the reader to understand the main concepts being discussed.

Organization of the Book

In Chapter 1 we share some of our experience with the work on this topic, illustrate the history, and provide you with our reasons for writing this book.

To our surprise, it was quite difficult to group the work on emergency services in a coherent fashion. We nevertheless gave it a try and separated the work on location (see Chapter 2) from emergency services architectures (see Chapter 3). It turns out that the work on certain location protocols and formats is very much driven by the architectural spirit the designers had in mind at the start of their work. Over time, others joined the work, and the desire to support the same protocol for many different deployment models then influenced further work, and extensions then offered different architectural models.

Roughly at the same time as the standardization work took place, various national organizations started brainstorming about transitioning toward the standardized next-generation emergency services architecture, taking their country-specific deployment constraints into account. We present four of these projects in Chapter 4. While each of these projects has their own history and their own challenges, they illustrate the complexity of the work to accomplish the goal of global emergency services interoperability.

In Chapter 5 we cover a topic that often surfaces in discussions, namely security. Today’s emergency services system is already subject to a number of attacks (in the form of false calls, hoax calls, and “swatting”), consuming valuable resources of call-takers and first responders. In some cases, lives are put at risk. Many worry that the problems we see on the Internet with malware, botnets, and distributed denial-of-service attacks will leave the future emergency services system even more vulnerable. In this chapter, we have tried to untangle various security threats and discuss ways to mitigate them.

IP-based communication architectures offer more flexibility and extensibility than the legacy communication architecture, since it is based on core Internet design principles, such as the end-to-end principle. This also provides better support for communication services for persons with disabilities in the form of multimedia communication. In Chapter 6 we exclusively focus on this topic.

Offering emergency services support for citizens and individuals is expensive, and in many cases key stakeholders do not have enough economic incentives to offer support for it. For this reason, regulatory agencies pay attention to this topic to steer the development. In Chapter 7 we illustrate the regulatory developments in the United States and in Europe. We expect to see many changes in this area as more and more users switch to IP-based services and legacy technology ceases to exist.

In Chapter 8 we illustrate three government-funded projects that support the work on IP-based emergency services and highlight their goals and observations.

In Chapter 9 we present a list of organizations that many of our readers may not be familiar with. With short descriptions of what these organizations are working on and what their goals are, we hope to widen your understanding of the bigger picture.

We offer our conclusions and an outlook in Chapter 10.

Scope

It may surprise you that emergency services is a large field. This book covers only a small part of the landscape, since it focuses mainly on the communication chain from an emergency caller dialing 9-1-1, 1-1-2, or any other emergency number that is supported in a certain region, to the call-takers, who receive your call at a Public Safety Answering Point (PSAP) and dispatch emergency personnel (also called first responders).

In this book we do not cover the following:

The communication from the PSAP toward the first responders (which in most parts of the world still use dedicated radio technology, such as Terrestrial Trunked Radio (TETRA))

The communication from public safety authorities toward citizens and individuals before, during, and after emergency situations. This body of work is often called “early warning,” and there is a large community working on standards and operational matters. Interestingly, the community working on early warning is largely distinct from those working on the classical 9-1-1, 1-1-2,…emergency service communication

A detailed description of the legacy telecommunication system and its emergency services architecture

Details about the underlying communication infrastructure. As such, this book does not replace the need to read books about the IP Multimedia Subsystem (IMS), Voice-over-IP system, Real-Time Web Communication, or about the eXtensible Messaging and Presence Protocol (XMPP)

Any form of social media for usage in disaster response and emergency management

If you would like to give us your feedback, please send us an email (hgs@cs.columbia.edu or hannes.tschofenig@gmx.net) or visit our webpage (http://ip-emergency.net).

Hannes Tschofenig
Nokia Siemens Networks

Henning Schulzrinne
Columbia University

Acknowledgments

The work on this book took a long time, much longer than we had initially anticipated. While working on advancing the emergency services and while writing the book, we talked to many experts in the field to ask for their input and their feedback. We both have been very active in the IETF, NENA, and EENA. While many discussions take place in online mailing lists and phone conference calls, there have also been many workshops where we have met other experts face-to-face. Owing to our involvement in various discussions, we have also been in contact with various emergency services organizations all over the world, software developers, communication service providers, Internet Service Providers, and various other stakeholders, who contribute to the success of the emergency services infrastructure.

It is difficult, if not impossible, to list a few persons in this section since so many have shaped our thinking in the work on emergency services and have contributed to all the topics included in this book. If you look at the individual chapters and follow the references, you will notice that many individuals have worked on the specifications and each document has a story; some documents have taken years to complete and have received a lot of attention. On top of the work on the specifications, there is an even larger group who develop code, and integrate various protocol implementations into complete products, and finally there is the wider community that deploys and uses those products, ranging from voice application client software to a PSAP call-center installation.

We would particularly like to thank our contributors for providing various chapters in this book. They have obviously done a significant part of the work to turn this book into a reality.

We would also like to thank our contact persons at John Wiley & Sons for their patience and for their guidance. In particular, we would like to thank Anna Smart, Susan Barclay, and Tiina Wigley.

A big thanks also goes to Jean Mahoney for reviewing and correcting several chapters in this book. Additionally, we would like to thank Spencer Dawkins, Andrew Newton, and Jean-Jacques Sahel for their review comments.

Finally, in advance, we thank those readers whom we expect to contact us with questions and suggestions for a future edition of this book, since the emergency services topic is by no means a completed area of work.

The editors and contributors welcome comments, questions or suggestions. Feedback can be sent to the editors via email (hgs@cs.columbia.edu or hannes.tschofenig@gmx.net) or by posting your remarks on our webpage (http://ip-emergency.net).

Acronyms

3G | 3rd Generation (Mobile Systems)
3GPP | 3rd Generation Partnership Program
3GPP2 | 3rd Generation Partnership Project 2
AAA | Authentication, Authorization and Accounting
AC | Access Class
AFLT | Advanced Forward Link Trilateration
A-GNSS | Assisted GNSS
A-GPS | Assisted GPS
ALI | Automatic Location Identification
AN | Access Network
ANI | Automatic Number Identification
AP | Access Point
APCO | Association of Public Safety Communications Officials
ASN | Access Service Network
ASN-GW | ASN Gateway
ASP | Application Service Provider
ASWG | Address Standard Working Group
ATIS | Alliance for Telecommunications Industry Solutions
ATIS-ESIF | Alliance for Telecommunications Industry Solutions – Emergency Services Interconnection Forum
B2BUA | Back-to-Back User Agent
BCF | Border Control Function
BEREC | Body of European Regulators for Electronic Communications
BS | Base Station
BTS | Base Transceiver Station
CA | Certificate Authority
CAD | Computer-Aided Dispatch
CAP | Common Alerting Protocol
CDMA | Code Division Multiple Access
CGALIES | Coordination Group on Access to Location Information by Emergency Services
CID | Call Information Database
CID | Cell ID
cid | Content Indirection
CLDXF | Civic Location Data Exchange Format
CLF | Connectivity Session Location and Repository Function
CN | Core Network
COMREG | Commission for Communications Regulation
CPE | Customer Premises Equipment
CRL | Certificate Revocation List
CRN | Contingency Routing Number
CRTC | Canadian Radio-television and Telecommunications Commission
CS | Circuit Switched
CSCF | Call Session Control Function
CSG | Closed Subscriber Group
CSN | Connectivity Service Network
CSP | Communication Service Provider
DHCP | Dynamic Host Configuration Protocol
DNS | Domain Name Server (or Service or System)
DoS | Denial of Service
DSAC | Domain Specific Access Control
DSL | Digital Subscriber Line
E9-1-1 | Enhanced 9-1-1
EAP | Extensible Authentication Protocol
E-CID | Enhanced CID
ECRF | Emergency Call Routing Function
ECRIT | Emergency Context Resolution with Internet Technologies
E-CSCF | Emergency Call Session Control Function
EENA | European Emergency Number Association
EHA | Emergency Handling Authorities
EMM | EPS Mobility Management
eNodeB | Evolved Node B
E-OTD | Enhanced Observed Time Difference
EPLMN | Equivalent PLMN
EPS | Evolved Packet System
EPSG/OGP | European Petroleum Survey Group/International Association of Oil and Gas Producers
ERDB | Emergency Service Zone Routing Data Base
ERT | Emergency Route Tuple
ESGW | Emergency Services Gateway
ESGWRI | Emergency Services Gateway Route Identifier
ESINet | Emergency Services IP Network
E-SLP | Emergency SLP
ESM | EPS Session Management
E-SMLC | Evolved Serving Mobile Location Center
ESN | Emergency Service Number, Electronic Serial Number, Emergency Service Network
ESNet | Emergency Services Network
ESQK | Emergency Services Query Key
ESRD | Emergency Services Routing Digits
ESRK | Emergency Services Routing Key
ESRP | Emergency Services Routing Proxy
ESZ | Emergency Services Zone (Same as ESN)
ETSI | European Telecommunications Standards Institute (ETSI)
E-UTRAN | Evolved Universal Terrestrial Radio Access Network
FCC | Federal Communications Commission
FGDC | US Federal Geographic Data Committee
FICORA | Finnish Communication Regulatory Authority
FLAP | Flexible Location server to AMF Protocol
Geopriv | Geolocation and Privacy
GeoRSS | Geodetic Really Simple Syndication
GERAN | GSM EDGE Radio Access Network
GML | Geographic Markup Language
GMLC | Gateway Mobile Location Center
GMM | GPRS Mobility Management
GMSC | Gateway MSC
GNSS | Global Navigation Satellite System
GPRS | General Packet Radio Service
GPS | Global Positioning System
GSM | Global Standard for Mobile Communication
GUTI | Globally Unique Temporary Identity
HA | Home Agent
HELD | HTTP Enabled Location Delivery
H-GMLC | Home GMLC
HLR | Home Location Register
HPLMN | Home PLMN
HSA | Home Subscription Agent
H-SLP | Home SLP
H-SPC | Home SPC
HSS | Home Subscriber Server
HTTP | Hypertext Transfer Protocol
IAIC | IP to ISP Address Converter
IANA | Internet Assigned Numbers Authority
IAP | Internet Access Provider
I-CSCF | Interrogating Call Session Control Function
IEEE | Institute of Electrical and Electronics Engineers
IETF | Internet Engineering Task Force
ILP | Internal Location Protocol
IM | Instant Messaging
IMEI | International Mobile Equipment Identity
IMS | IP Multimedia Subsystem
IMSI | International Mobile Subscriber Identity
IP | Internet Protocol
IPsec | Internet Protocol Security
ISP | Internet Service Provider
ITU | International Telecommunications Union
LA | Location Agent
LBS | Location Based Services
LbyR | Location by Reference
LbyV | Location by Value
LC | Location Controller
LCP | Location Configuration Protocol
LCS | Location Service
LIF | Location Interoperability Forum
LIMS-IWF | Location IMS – Interworking Function
LIS | Location Information Server
LMU | Location Measurement Unit
LNG | Legacy Network Gateway
LO | Location Object
LoST | Location to Service Translation
LPP | LTE Positioning Protocol
LR | Location Requester, Location Recipient
LRF | Location Retrieval Function
LRO | Last Routing Option
LS | Location Server
LTD | Long-Term Definition
LTE | Long-Term Evolution
LVF | Location Validation Function
MAC | Media Access Control
MCC | Mobile Country Code
MDN | Mobile Directory Number
ME | Mobile Equipment
MIN | Mobile Identification Number
MIP | Mobile IP
MLP | Mobile Location Protocol
MLS | Mobile Location Service
MME | Mobility Management Entity
MNC | Mobile Network Code
MO | Mobile Originating (call)
MS | Mobile Station
MSAG | Master Street Address Guide
MSC | Mobile Switching Center
MSISDN | Mobile Station International ISDN Number
MSRP | Message Session Relay Protocol
NAD83 | North American Datum 1983
NAI | Network Access Identifier
NAP | Network Access Provider
NAPTR | Naming Authority Pointer
NAS | Network Attachment Subsystem
NAT | Network Address Translation
NAVD88 | North American Vertical Datum of 1988
ND&S | Network Discovery and Selection
NENA | National Emergency Number Association
NG112 | Next Generation 112
NG9-1-1 | Next Generation 9-1-1
NGO | Non-Governmental Organization
NICC | Network Interoperability Consultative Committee
NRA | National Regulatory Authority
NRM | Network Reference Model
NSP | Network Service Provider
NWG | Network Working Group
OFCOM | Office of Communications
OGC | Open Geospatial Consortium
OMA | Open Mobile Alliance
O-TDOA | Observed Time Difference of Arrival
PAI | P-Asserted Identity
PCC | Policy and Charging Control
PCP | Privacy Checking Protocol
PCRF | Policy Control and Charging Rules Function
P-CSCF | Proxy Call State Control Function
Phone | Either ME or UE
PIDF | Presence Information Data Format
PIDF-LO | Presence Information Data Format – Location Object
PKI | Public-Key Infrastructure
PLMN | Public Land Mobile Network
PMD | Pseudonym Mediation Device functionality
PMIP | Proxy Mobile IP
PPAC | Paging Permission Access Control
PPR | Privacy Profile Register
PS | Packet Switched
PSAP | Public Safety Answering Point
PSK-TLS | Pre-Shared Key TLS
PSTN | Public Switched Telephone Network
QoP | Quality of Position
QoS | Quality of Service
RADIUS | Remote Access Dial-In User Service
RAU | Routing Area Update
RDF | Routing Determination Function
RDS | Root Discovery Server
RFC | Request For Comment
R-GMLC | Requesting GMLC
RNC | Radio Network Controller
RRC | Radio Resource Control
RRLP | Radio Resource LCS Protocol
RTCP | Real Time Control Protocol
RTP | Real Time Transport Protocol
RTSP | Real Time Streaming Protocol
RTT | Real Time Text
SAI | Service Area Identity
SAS | Standalone SMLC
SBC | Session Border Control
S-CSCF | Serving CSCF
SDES | Session Description Protocol Security Descriptions
SDO | Standards Development Organization
SDP | Session Description Protocol
SET | SUPL Enabled Terminal
SGSN | Serving GPRS Support Node
SIM | Subscriber Identity Module
SIP | Session Initiation Protocol
SLA | SUPL Location Agent
SLC | SUPL Location Center
SLP | SUPL Location Platform
SMS | Short Message Service
SPC | SUPL Positioning Center
SRDB | Selective Routing Database
SRTP | Secure Real Time Transport Protocol
SRVCC | Single Radio Voice Call Continuity
SS | Subscriber Station
SSAC | Service Specific Access Control
STA | Station (an entity with 802.11 interface)
SUPL | Secure User Plane Location
TAU | Tracking Area Update
TCP | Transmission Control Protocol
TDD | Telecommunications Device for the Deaf and Hard-of-Hearing
TLS | Transport Layer Security
TMSI | Temporary Mobile Subscriber Identity
TTY | Teletypewriter (a.k.a. TDD)
UA | User Agent
UAC | User Agent Client
UAS | User Agent Server
UDP | User Datagram Protocol
UE | User Equipment
ULP | Userplane Location Protocol
UMB | Ultra Mobile Broadband
U-NAPTR | Straightforward URI-Enabled NAPTR
URI | Uniform Resource Identifier
URL | Uniform Resource Locator
URN | Uniform Resource Name
USI | Universal Services Interface
USIM | UMTS Subscriber Identity Module
U-TDOA | Uplink-Time Difference of Arrival
UTRAN | Universal Terrestrial Radio Access Network
VCC | Voice Call Continuity
VDB | Validation Database
V-GMLC | Visited GMLC
VLR | Visitor Location Register
VLS | Visited Location Server
VMSC | Visited MSC
VoIP | Voice over IP
VPC | VoIP Positioning Center
VPLMN | Visited PLMN
VPN | Virtual Private Network
VSP | VoIP Service Provider
WCDMA | Wideband Code Division Multiple Access
WebRTC | Web Real-Time Communication
WiFi | WLAN based on IEEE802.11
WiMAX | Worldwide Interoperability for Microwave Access
WLP | WiMAX Location Protocol
XML | eXtensible Markup Language
XMPP | eXtensible Messaging and Presence Protocol

1

Introduction

In an August 2011 interview, Federal Communications Commission (FCC) Chairman Julius Genachowski said that “It’s hard to imagine that airlines can send text messages if your flight is delayed, but you can’t send a text message to 911 in an emergency.” He continued “The unfortunate truth is that the capability of our emergency-response communications has not kept pace with commercial innovation, has not kept pace with what ordinary people now do every day with communications devices” [1].

Vice Presidents of the European Commission Neelie Kroes and Siim Kallas have decided to work together to ensure every European can access a 112 smart-phone application, in their own language. This announcement was made in February 2012 [2] on the European 112 day when surveys revealed that “74% of Europeans don’t know what emergency number to call when traveling in the European Union.”

In May 2012 Verizon Wireless announced that it will offer text-to-911 service nationwide to the public as the first US wireless carrier [3].

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!

Lesen Sie weiter in der vollständigen Ausgabe!