VoIP Emergency Calling: Foundations and Practice

VoIP EMERGENCY CALLING......Page 3
Contents......Page 7
Foreword......Page 11
Useful Links......Page 13
List of Abbreviations......Page 15
1 Introduction......Page 19
1.2 VoIP Emergency Calling Problem Statement......Page 20
1.3 Emergency Communication......Page 23
1.4 Overview of this Book......Page 24
References......Page 25
2.1 Overview......Page 27
2.2 Infrastructure Requirements......Page 28
2.3 The Role of Location Information......Page 30
References......Page 34
3 The ECRIT Emergency Calling Architecture......Page 37
3.1 Overview......Page 38
3.2 Location Information......Page 40
3.2.1 PIDF-LO......Page 41
3.2.2 Location by Value and Location by Reference......Page 48
3.2.3 Location Conveyance......Page 51
3.3 Service URNs......Page 57
3.4 Determining the Appropriate PSAP – the LoST Protocol......Page 58
3.4.1 The Mapping Process – findService......Page 59
3.4.2 Retrieving the Service List – listServicesByLocation......Page 62
3.4.3 Address Validation......Page 64
3.4.4 Areas of Responsibility – serviceBoundary......Page 65
3.4.5 LoST Server Discovery......Page 67
3.4.6 LoST Architecture......Page 68
3.4.7 Private and Public LoST Trees......Page 71
3.4.8 LoST Synchronization......Page 72
3.5 The Emergency Call Itself......Page 75
3.5.1 Initiating Emergency Calls......Page 76
3.5.2 Routing Emergency Calls......Page 78
3.5.3 Assembling the SIP INVITE Message......Page 79
3.6 Home Dial String Configuration via LoST......Page 80
3.7 Deployment Models......Page 84
3.8 Considerations for Proxies......Page 87
3.9 Standardization......Page 89
3.10 Summary......Page 91
References......Page 92
4 Including Location Information......Page 95
4.1.1 HTTP Enabled Location Delivery (HELD)......Page 96
4.1.2 DHCP Options for Location Configuration......Page 102
4.1.3 LLDP-MED......Page 104
4.1.5 Conversion between Location Formats......Page 106
4.2 Positioning Using GPS......Page 108
4.3 Network-Based Positioning......Page 109
4.4 Location Hiding......Page 110
References......Page 112
5 Implementation and Regulatory Considerations......Page 115
5.1.1 Emergency Call Centers (PSAPs)......Page 116
5.1.2 VoIP Software and Hardware Manufacturers......Page 117
5.1.3 Network Operators and ISPs......Page 118
5.1.4 VoIP Operators......Page 119
5.1.6 Unassigned Responsibilities......Page 120
5.2 Austria......Page 121
5.2.2 KEM-V......Page 122
5.2.3 RTR Guidelines for VoIP Operators......Page 123
5.2.4 AK-TK Recommendations......Page 124
5.2.5 Emergency Calling in Austria......Page 125
5.3 The United States......Page 130
5.3.1 9-1-1 Regulation......Page 131
5.3.2 9-1-1 History......Page 134
5.3.3 Automatic Location Information......Page 138
5.4 The European Union......Page 140
5.5.1 Regulatory Framework......Page 141
5.5.2 Call Handling......Page 144
5.5.3 Location Information and Privacy......Page 145
5.6 Summary......Page 147
References......Page 148
6.1 Software......Page 151
6.1.1 HELD Clients and Servers......Page 152
6.1.2 DHCP Location Encoders and Decoders......Page 155
6.1.4 OpenLLDP......Page 157
6.1.5 HELD Support in Firefox......Page 158
6.1.6 LoST Implementations......Page 159
6.1.7 Zap! with Emergency Calling Extensions......Page 160
6.1.8 Ecritdroid......Page 163
6.1.9 EcritXUL......Page 165
6.1.10 Multi-Part Body Extension to Asterisk......Page 167
6.1.11 IMS Core Emergency Services......Page 168
6.2 Practice Exercises......Page 169
6.2.1 Location Configuration: DHCPv4 with Civic Addresses......Page 170
6.2.2 Location Configuration: Simulating a HELD Server......Page 173
6.2.3 Location Configuration: Location-Enabling a Network with HELD......Page 174
6.2.4 Mapping: Querying the LoST Server......Page 178
6.2.5 SIP Calling: Call Setup with Location Configuration......Page 180
6.2.6 ECRIT Calling: A Complete System......Page 184
References......Page 188
7 Security......Page 189
7.1.1 Determining the Caller’s Location......Page 190
7.1.3 Delivering the Call......Page 193
7.1.4 Considerations for Proxies......Page 194
7.2 Location Security......Page 195
7.2.1 Location Privacy......Page 196
7.2.2 Location Assurance......Page 200
7.2.3 Location Protection......Page 202
7.3 PSAP and VoIP Network Security......Page 204
7.3.1 Basic PSAP Protection Measures......Page 205
7.3.2 PSAP Fraud Mitigation......Page 206
7.3.3 VoIP Provider Call Validation......Page 210
References......Page 213
8 Ongoing Emergency Calling Work......Page 215
8.1 Prototyping, Implementation, and Interoperability......Page 216
8.2.2 Unauthenticated Emergency Calls......Page 218
8.2.4 Home Emergency Dial String Issues......Page 219
8.2.5 Updating the List of Available Emergency Services – the LoST Service List Boundary......Page 220
8.2.6 Order of Location Configuration......Page 222
8.2.8 Connecting Emergency Dial Strings and Emergency Authorities......Page 223
8.2.11 Civic Boundaries......Page 224
8.2.12 LoST Service Boundary References and Location Types......Page 225
8.2.13 Emergency Calls to Counseling Services......Page 226
8.3.2 Converting from the DHCP Location Format to PIDF-LO......Page 227
8.3.4 Multi-Part SIP Bodies and Message Size......Page 228
References......Page 229
9 Summary and the Outlook for the Future......Page 231
Index......Page 235