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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) ** Obsolete normative reference: RFC 5226 (Obsoleted by RFC 8126) == Outdated reference: draft-ietf-ecrit-car-crash has been published as RFC 8148 Summary: 1 error (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 ECRIT R. Gellens 3 Internet-Draft Core Technology Consulting 4 Intended status: Standards Track H. Tschofenig 5 Expires: July 15, 2017 Individual 6 January 11, 2017 8 Next-Generation Pan-European eCall 9 draft-ietf-ecrit-ecall-22.txt 11 Abstract 13 This document describes how to use IP-based emergency services 14 mechanisms to support the next generation of the pan European in- 15 vehicle emergency call service defined under the eSafety initiative 16 of the European Commission (generally referred to as "eCall"). eCall 17 is a standardized and mandated system for a special form of emergency 18 calls placed by vehicles, providing real-time communications and an 19 integrated set of related data. 21 This document also registers MIME media types and an Emergency Call 22 Additional Data Block for the eCall vehicle data and metadata/control 23 data, and an INFO package to enable carrying this data in SIP INFO 24 requests. 26 Although this specification is designed to meet the requirements of 27 European next-generation eCall, it is specified generically such that 28 the technology can be re-used or extended to suit requirements across 29 jurisdictions. 31 Status of This Memo 33 This Internet-Draft is submitted in full conformance with the 34 provisions of BCP 78 and BCP 79. 36 Internet-Drafts are working documents of the Internet Engineering 37 Task Force (IETF). Note that other groups may also distribute 38 working documents as Internet-Drafts. The list of current Internet- 39 Drafts is at http://datatracker.ietf.org/drafts/current/. 41 Internet-Drafts are draft documents valid for a maximum of six months 42 and may be updated, replaced, or obsoleted by other documents at any 43 time. It is inappropriate to use Internet-Drafts as reference 44 material or to cite them other than as "work in progress." 46 This Internet-Draft will expire on July 15, 2017. 48 Copyright Notice 50 Copyright (c) 2017 IETF Trust and the persons identified as the 51 document authors. All rights reserved. 53 This document is subject to BCP 78 and the IETF Trust's Legal 54 Provisions Relating to IETF Documents 55 (http://trustee.ietf.org/license-info) in effect on the date of 56 publication of this document. Please review these documents 57 carefully, as they describe your rights and restrictions with respect 58 to this document. Code Components extracted from this document must 59 include Simplified BSD License text as described in Section 4.e of 60 the Trust Legal Provisions and are provided without warranty as 61 described in the Simplified BSD License. 63 Table of Contents 65 1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 66 2. Document Scope . . . . . . . . . . . . . . . . . . . . . . . 4 67 3. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5 68 4. eCall Requirements . . . . . . . . . . . . . . . . . . . . . 7 69 5. Vehicle Data . . . . . . . . . . . . . . . . . . . . . . . . 7 70 6. Data Transport . . . . . . . . . . . . . . . . . . . . . . . 7 71 7. Call Setup . . . . . . . . . . . . . . . . . . . . . . . . . 10 72 8. Test Calls . . . . . . . . . . . . . . . . . . . . . . . . . 11 73 9. The Metadata/Control Object . . . . . . . . . . . . . . . . . 11 74 9.1. The Control Block . . . . . . . . . . . . . . . . . . . . 13 75 9.1.1. The element . . . . . . . . . . . . . . . . . . 13 76 9.1.1.1. Attributes of the element . . . . . . . . . 14 77 9.1.1.2. Child Element of the element . . . . . . . 14 78 9.1.1.3. Ack Examples . . . . . . . . . . . . . . . . . . 15 79 9.1.2. The element . . . . . . . . . . . . . 15 80 9.1.2.1. Child Element of the element . . . 15 81 9.1.2.2. Capabilities Example . . . . . . . . . . . . . . 16 82 9.1.3. The element . . . . . . . . . . . . . . . . 16 83 9.1.3.1. Attributes of the element . . . . . . . 17 84 9.1.3.2. Request Example . . . . . . . . . . . . . . . . . 18 85 10. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 18 86 11. Security Considerations . . . . . . . . . . . . . . . . . . . 24 87 12. Privacy Considerations . . . . . . . . . . . . . . . . . . . 25 88 13. XML Schema . . . . . . . . . . . . . . . . . . . . . . . . . 26 89 14. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28 90 14.1. The EmergencyCallData Media Subtree . . . . . . . . . . 28 91 14.2. Service URN Registrations . . . . . . . . . . . . . . . 29 92 14.3. MIME Media Type Registration for 93 'application/emergencyCallData.eCall.MSD+per' . . . . . 29 94 14.4. MIME Media Type Registration for 95 'application/emergencyCallData.control+xml' . . . . . . 31 97 14.5. Registration of the 'eCall.MSD' entry in the Emergency 98 Call Additional Data Types registry . . . . . . . . . . 32 99 14.6. Registration of the 'control' entry in the Emergency 100 Call Additional Data Types registry . . . . . . . . . . 32 101 14.7. URN Sub-Namespace Registration . . . . . . . . . . . . . 33 102 14.7.1. Registration for urn:ietf:params:xml:ns:eCall . . . 33 103 14.7.2. Registration for urn:ietf:params:xml:ns:control . . 33 104 14.8. Registry Creation . . . . . . . . . . . . . . . . . . . 34 105 14.8.1. Emergency Call Action Registry . . . . . . . . . . . 34 106 14.8.2. Emergency Call Action Failure Reason Registry . . . 35 107 14.9. The emergencyCallData.eCall.MSD INFO package . . . . . . 36 108 14.9.1. Overall Description . . . . . . . . . . . . . . . . 36 109 14.9.2. Applicability . . . . . . . . . . . . . . . . . . . 36 110 14.9.3. Info Package Name . . . . . . . . . . . . . . . . . 37 111 14.9.4. Info Package Parameters . . . . . . . . . . . . . . 37 112 14.9.5. SIP Option-Tags . . . . . . . . . . . . . . . . . . 37 113 14.9.6. INFO Request Body Parts . . . . . . . . . . . . . . 37 114 14.9.7. Info Package Usage Restrictions . . . . . . . . . . 38 115 14.9.8. Rate of INFO Requests . . . . . . . . . . . . . . . 38 116 14.9.9. Info Package Security Considerations . . . . . . . . 38 117 14.9.10. Implementation Details . . . . . . . . . . . . . . . 38 118 14.9.11. Examples . . . . . . . . . . . . . . . . . . . . . . 38 119 15. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 38 120 16. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 39 121 17. Changes from Previous Versions . . . . . . . . . . . . . . . 39 122 17.1. Changes from draft-ietf-19 to draft-ietf-20 . . . . . . 39 123 17.2. Changes from draft-ietf-18 to draft-ietf-19 . . . . . . 39 124 17.3. Changes from draft-ietf-17 to draft-ietf-18 . . . . . . 39 125 17.4. Changes from draft-ietf-16 to draft-ietf-17 . . . . . . 39 126 17.5. Changes from draft-ietf-15 to draft-ietf-16 . . . . . . 39 127 17.6. Changes from draft-ietf-14 to draft-ietf-15 . . . . . . 40 128 17.7. Changes from draft-ietf-13 to draft-ietf-14 . . . . . . 40 129 17.8. Changes from draft-ietf-12 to draft-ietf-13 . . . . . . 40 130 17.9. Changes from draft-ietf-11 to draft-ietf-12 . . . . . . 40 131 17.10. Changes from draft-ietf-09 to draft-ietf-11 . . . . . . 40 132 17.11. Changes from draft-ietf-08 to draft-ietf-09 . . . . . . 41 133 17.12. Changes from draft-ietf-07 to draft-ietf-08 . . . . . . 41 134 17.13. Changes from draft-ietf-06 to draft-ietf-07 . . . . . . 41 135 17.14. Changes from draft-ietf-05 to draft-ietf-06 . . . . . . 42 136 17.15. Changes from draft-ietf-04 to draft-ietf-05 . . . . . . 42 137 17.16. Changes from draft-ietf-03 to draft-ietf-04 . . . . . . 42 138 17.17. Changes from draft-ietf-02 to draft-ietf-03 . . . . . . 42 139 17.18. Changes from draft-ietf-01 to draft-ietf-02 . . . . . . 42 140 17.19. Changes from draft-ietf-00 to draft-ietf-01 . . . . . . 43 141 17.20. Changes from draft-gellens-03 to draft-ietf-00 . . . . . 43 142 17.21. Changes from draft-gellens-02 to -03 . . . . . . . . . . 43 143 17.22. Changes from draft-gellens-01 to -02 . . . . . . . . . . 43 144 17.23. Changes from draft-gellens-00 to -01 . . . . . . . . . . 43 146 18. References . . . . . . . . . . . . . . . . . . . . . . . . . 43 147 18.1. Normative References . . . . . . . . . . . . . . . . . . 44 148 18.2. Informative references . . . . . . . . . . . . . . . . . 45 149 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 46 151 1. Terminology 153 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 154 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 155 document are to be interpreted as described in [RFC2119]. 157 This document re-uses terminology defined in Section 3 of [RFC5012]. 159 Additionally, we use the following abbreviations: 161 +--------+----------------------------------------+ 162 | Term | Expansion | 163 +--------+----------------------------------------+ 164 | 3GPP | 3rd Generation Partnership Project | 165 | | | 166 | CEN | European Committee for Standardization | 167 | | | 168 | EENA | European Emergency Number Association | 169 | | | 170 | ESInet | Emergency Services IP network | 171 | | | 172 | IMS | IP Multimedia Subsystem | 173 | | | 174 | IVS | In-Vehicle System | 175 | | | 176 | MNO | Mobile Network Operator | 177 | | | 178 | MSD | Minimum Set of Data | 179 | | | 180 | PSAP | Public Safety Answering Point | 181 +--------+----------------------------------------+ 183 2. Document Scope 185 This document is focused on the signaling, data exchange, and 186 protocol needs of next-generation eCall (NG-eCall, also referred to 187 as packet-switched eCall or all-IP eCall) within the SIP framework 188 for emergency calls (as described in [RFC6443] and [RFC6881]). eCall 189 itself is specified by 3GPP (3rd Generation Partnership Project) and 190 CEN (European Committee for Standardization) and these specifications 191 include far greater scope than is covered here. 193 The eCall service operates over cellular wireless communication, but 194 this document does not address cellular-specific details, nor client 195 domain selection (e.g., circuit-switched versus packet-switched). 196 All such aspects are the purview of their respective standards 197 bodies. The scope of this document is limited to eCall operating 198 within a SIP-based environment (e.g., 3GPP IMS Emergency Calling 199 [TS23.167]). 201 Although this specification is designed to meet the requirements of 202 pan-European next-generation eCall, it is specified generically such 203 that the technology can be re-used or extended to suit requirements 204 across jurisdictions (see, e.g., [I-D.ietf-ecrit-car-crash]), and 205 extension points are provided to facilitate this. 207 Note that vehicles designed for multiple regions might need to 208 support eCall and other Advanced Automatic Crash Notification (AACN) 209 systems (such as described in [I-D.ietf-ecrit-car-crash]), but this 210 is out of scope of this document. 212 3. Introduction 214 Emergency calls made from vehicles (e.g., in the event of a crash) 215 assist in significantly reducing road deaths and injuries by allowing 216 emergency services to be aware of the incident, the state of the 217 vehicle, the location of the vehicle, and to have a voice channel 218 with the vehicle occupants. This enables a quick and appropriate 219 response. 221 The European Commission initiative of eCall was conceived in the late 222 1990s, and has evolved to a European Parliament decision requiring 223 the implementation of a compliant in-vehicle system (IVS) in new 224 vehicles and the deployment of eCall in the European Member States in 225 the very near future. Other regions are developing eCall-compatible 226 systems. 228 The pan-European eCall system is a standardized and mandated 229 mechanism for emergency calls by vehicles, providing a voice channel 230 and transmission of data. eCall establishes procedures for such 231 calls to be placed by in-vehicle systems, recognized and processed by 232 the mobile network, and routed to a specialized PSAP where the 233 vehicle data is available to assist the call taker in assessing and 234 responding to the situation. eCall provides a standard set of 235 vehicle, sensor (e.g., crash related), and location data. 237 An eCall can be either user-initiated or automatically triggered. 238 Automatically triggered eCalls indicate a car crash or some other 239 serious incident. Manually triggered eCalls might be reports of 240 witnessed crashes or serious hazards. PSAPs might apply specific 241 operational handling to manual and automatic eCalls. 243 Legacy eCall is standardized (by 3GPP [SDO-3GPP] and CEN [CEN]) as a 244 3GPP circuit-switched call over GSM (2G) or UMTS (3G). Flags in the 245 call setup mark the call as an eCall, and further indicate if the 246 call was automatically or manually triggered. The call is routed to 247 an eCall-capable PSAP, a voice channel is established between the 248 vehicle and the PSAP, and an eCall in-band modem is used to carry a 249 defined set of vehicle, sensor (e.g., crash related), and location 250 data (the Minimum Set of Data or MSD) within the voice channel. The 251 same in-band mechanism is used for the PSAP to acknowledge successful 252 receipt of the MSD, and to request the vehicle to send a new MSD 253 (e.g., to check if the state of or location of the vehicle or its 254 occupants has changed). NG-eCall moves from circuit switched to all- 255 IP, and carries the vehicle data and eCall signaling as additional 256 data carried with the call. This document describes how IETF 257 mechanisms for IP-based emergency calls (including [RFC6443] and 258 [RFC7852]) are used to provide the signaling and data exchange of the 259 next generation of pan-European eCall. 261 The European Telecommunications Standards Institute (ETSI) [SDO-ETSI] 262 has published a Technical Report titled "Mobile Standards Group 263 (MSG); eCall for VoIP" [MSG_TR] that presents findings and 264 recommendations regarding support for eCall in an all-IP environment. 265 The recommendations include the use of 3GPP IMS emergency calling 266 with additional elements identifying the call as an eCall and as 267 carrying eCall data and with mechanisms for carrying the data and 268 eCall signaling. 3GPP IMS emergency services support multimedia, 269 providing the ability to carry voice, text, and video. This 270 capability is referred to within 3GPP as Multimedia Emergency 271 Services (MMES). 273 A transition period will exist during which time the various entities 274 involved in initiating and handling an eCall might support next- 275 generation eCall, legacy eCall, or both. The issues of migration and 276 co-existence during the transition period are outside the scope of 277 this document. 279 This document indicates how to use IP-based emergency services 280 mechanisms to support next-generation eCall. 282 This document also registers MIME media types and an Emergency Call 283 Additional Data Block for the eCall vehicle data (MSD) and metadata/ 284 control data, and an INFO package to enable carrying this data in SIP 285 INFO requests. 287 The MSD is carried in the MIME type 'application/ 288 emergencyCallData.eCall.MSD+per' and the metadata/control block is 289 carried in the MIME type 'application/emergencyCallData.control+xml' 290 (both of which are registered in Section 14). An INFO package is 291 defined (in Section 14.9) to enable these MIME types to be carried in 292 SIP INFO requests, per [RFC6086]. 294 4. eCall Requirements 296 eCall requirements are specified by CEN in [EN_16072] and by 3GPP in 297 [TS22.101] clauses 10.7 and A.27 and [TS24.229] section 4.7.6. 298 Requirements specific to vehicle data are contained in EN 15722 299 [msd]. 301 5. Vehicle Data 303 Pan-European eCall provides a standardized and mandated set of 304 vehicle related data (including VIN, vehicle type, propulsion type, 305 current and optionally previous location coordinates, and number of 306 occupants), known as the Minimum Set of Data (MSD). The European 307 Committee for Standardization (CEN) has specified this data in EN 308 15722 [msd], along with both ASN.1 and XML encodings. Both circuit- 309 switched eCall and this document use the ASN.1 PER encoding, which is 310 specified in Annex A of EN 15722 [msd] (the XML encoding specified in 311 Annex C is not used in this document, per 3GPP [SDO-3GPP]). 313 This document registers the 'application/ 314 emergencyCallData.eCall.MSD+per' MIME media type to enable the MSD to 315 be carried in SIP. As an ASN.1 PER encoded object, the data is 316 binary and transported using binary content transfer encoding within 317 SIP messages. This document also adds the 'eCall.MSD' entry to the 318 Emergency Call Additional Data Types registry to enable the MSD to be 319 recognized as such in a SIP-based eCall emergency call. (See 320 [RFC7852] for more information about the registry and how it is 321 used.) 323 See Section 6 for a discussion of how the MSD vehicle data is 324 conveyed in an NG-eCall. 326 6. Data Transport 328 [RFC7852] establishes a general mechanism for conveying blocks of 329 data within a SIP emergency call. This document makes use of that 330 mechanism to include vehicle data (the MSD, see Section 5) and/or 331 metadata/control information (see Section 9) within SIP messages. 332 This document also registers an INFO package (in Section 14.9) to 333 enable eCall related data blocks to be carried in SIP INFO requests 334 (per [RFC6086], new INFO usages require the definition of an INFO 335 package). 337 Note that if other data sets need to be transmitted in the future, 338 the appropriate signalling mechanism for such data needs to be 339 evaluated, including factors such as the size and frequency of such 340 data. 342 An In-Vehicle System (IVS) transmits an MSD (see Section 5) by 343 encoding it per Annex A of EN 15722 [msd], and including it as a MIME 344 body part within a SIP message per [RFC7852]. The body part is 345 identified by its MIME media type ('application/ 346 emergencyCallData.eCall.MSD+per') in the Content-Type header field of 347 the body part. The body part is assigned a unique identifier which 348 is listed in a Content-ID header field in the body part. The SIP 349 message is marked as containing the MSD by adding (or appending to) a 350 Call-Info header field at the top level of the SIP message. This 351 Call-Info header field contains a CID URL referencing the body part's 352 unique identifier, and a 'purpose' parameter identifying the data as 353 the eCall MSD per the Emergency Call Additional Data Types registry 354 entry; the 'purpose' parameter's value is 355 'emergencyCallData.eCall.MSD'. Per [RFC6086], an MSD is carried in a 356 SIP INFO request by using the INFO package defined in Section 14.9. 358 A PSAP or IVS transmits a metadata/control object (see Section 9) by 359 encoding it per the description in this document, and including it 360 within a SIP message as a MIME body part per [RFC7852]. The body 361 part is identified by its MIME media type ('application/ 362 emergencyCallData.control+xml') in the Content-Type header field of 363 the body part. The body part is assigned a unique identifier which 364 is listed in a Content-ID header field in the body part. The SIP 365 message is marked as containing the metadata/control object by adding 366 (or appending to) a Call-Info header field at the top level of the 367 SIP message. This Call-Info header field contains a CID URL 368 referencing the body part's unique identifier, and a 'purpose' 369 parameter identifying the data as an eCall metadata/control block per 370 the Emergency Call Additional Data Types registry entry; the 371 'purpose' parameter's value is 'emergencyCallData.control'. Per 372 [RFC6086], a metadata/control object is carried in a SIP INFO request 373 by using the INFO package defined in Section 14.9. 375 An MSD or a metadata/control block is always enclosed in a multipart 376 (normally multipart/mixed) body part (even if it would otherwise be 377 the only body part in the SIP message), since as of the date of this 378 document, the use of Content-ID as a SIP header field is not defined 379 (while it is defined for use as a MIME header field). 381 A body part containing an MSD or metadata/control object has a 382 Content-Disposition header field value containing "By-Reference". 384 An In-Vehicle System (IVS) initiating an NG-eCall includes an MSD as 385 a body part within the initial INVITE, and optionally also includes a 386 metadata/control object informing the PSAP of its capabilities as 387 another body part. The MSD body part (and metadata/control and PIDF- 388 LO body parts if included) have a Content-Disposition header field 389 with the value "By-Reference; handling=optional". Specifying 390 "handling=optional" prevents the SIP INVITE request from being 391 rejected if it is processed by a legacy element (e.g., a gateway 392 between SIP and circuit-switched environments) that does not 393 understand the MSD (or metadata/control object or PIDF-LO). The PSAP 394 creates a metadata/control object acknowledging receipt of the MSD 395 and includes it as a body part within the SIP final response to the 396 SIP INVITE request per [RFC7852]. A metadata/control object is not 397 included in provisional (e.g., 180) responses. 399 A PSAP is able to reject a call while indicating that it is aware of 400 the situation by including a metadata/control object acknowledging 401 the MSD and containing "received=true" within a final response using 402 SIP response code 600 (Busy Everywhere), 486 (Busy Here), or 603 403 (Decline), per [RFC7852]. 405 If the IVS receives an acknowledgment for an MSD containing 406 "received=false", this indicates that the PSAP was unable to properly 407 decode or process the MSD. The IVS action is not defined (e.g., it 408 might only log an error). Since the PSAP is able to request an 409 updated MSD during the call, if an initial MSD is unsatisfactory in 410 any way, the PSAP can choose to request another one. 412 A PSAP can request that the vehicle send an updated MSD during a call 413 (e.g., upon manual request of the PSAP call taker who suspects 414 vehicle state may have changed.) To do so, the PSAP creates a 415 metadata/control object requesting an MSD and includes it within a 416 SIP INFO request sent within the dialog. The IVS then includes an 417 updated MSD within a SIP INFO request and sends it within the dialog. 418 If the IVS is unable to send an MSD, it instead sends a metadata/ 419 control object acknowledging the request with the 'success' parameter 420 set to 'false' and a 'reason' parameter (and optionally a 'details' 421 parameter) indicating why the request could not be accomplished. Per 422 [RFC6086], metadata/control objects and MSDs are sent using the INFO 423 package defined in Section 14.9. In addition, to align with how an 424 MSD or metadata/control block is transmitted in a SIP message other 425 than an INFO request, a Call-Info header field is included in the SIP 426 INFO request to reference the MSD or metadata/control block per 427 [RFC7852]. See Section 14.9 for information about the use of SIP 428 INFO requests to carry data within an eCall. 430 The IVS is not expected to send an unsolicited MSD after the initial 431 INVITE. 433 This document does not mandate support for the data blocks defined in 434 [RFC7852]. 436 7. Call Setup 438 In circuit-switched eCall, the IVS places a special form of a 112 439 emergency call which carries an eCall flag (indicating that the call 440 is an eCall and also if the call was manually or automatically 441 triggered); the mobile network operator (MNO) recognizes the eCall 442 flag and routes the call to an eCall-capable PSAP; vehicle data is 443 transmitted to the PSAP via the eCall in-band modem (in the voice 444 channel). 446 ///----\\\ 112 voice call with eCall flag +------+ 447 ||| IVS |||---------------------------------------->+ PSAP | 448 \\\----/// vehicle data via eCall in-band modem +------+ 450 Figure 1: circuit-switched eCall 452 For NG-eCall, the IVS establishes an emergency call using a Request- 453 URI indicating a manual or automatic eCall; the MNO (or ESInet) 454 recognizes the eCall URN and routes the call to an NG-eCall capable 455 PSAP; the PSAP interprets the vehicle data sent with the call and 456 makes it available to the call taker. 458 ///----\\\ IMS emergency call with eCall URN +------+ 459 IVS ----------------------------------------->+ PSAP | 460 \\\----/// vehicle data included in call setup +------+ 462 Figure 2: NG-eCall 464 See Section 6 for information on how the MSD is transported within an 465 NG-eCall. 467 This document registers new service URN children within the "sos" 468 subservice. These URNs provide the mechanism by which an eCall is 469 identified, and differentiate between manually and automatically 470 triggered eCalls (which might be subject to different treatment, 471 depending on policy). The two service URNs are: 472 urn:service:sos.ecall.automatic and urn:service:sos.ecall.manual, 473 which requests resources associated with an emergency call placed by 474 an in-vehicle system, carrying a standardized set of data related to 475 the vehicle and incident. 477 Call routing is outside the scope of this document. 479 8. Test Calls 481 eCall requires the ability to place test calls (see [TS22.101] clause 482 10.7 and [EN_16062] clause 7.2.2). These are calls that are 483 recognized and treated to some extent as eCalls but are not given 484 emergency call treatment and are not handled by call takers. The 485 specific handling of test eCalls is not itself standardized; 486 typically, the test call facility allows the IVS or user to verify 487 that an eCall can be successfully established with voice 488 communication. The IVS might also be able to verify that the MSD was 489 successfully received. 491 A service URN starting with "test." indicates a test call. For 492 eCall, "urn:service:test.sos.ecall" indicates such a test feature. 493 This functionality is defined in [RFC6881]. 495 This document registers "urn:service:test.sos.ecall" for eCall test 496 calls. 498 The circuit switched eCall test call facility is a non-emergency 499 number so does not get treated as an emergency call. For NG-eCall, 500 MNOs, emergency authorities, and PSAPs can determine how to treat a 501 vehicle call requesting the "test" service URN so that the desired 502 functionality is tested, but this is outside the scope of this 503 document. 505 9. The Metadata/Control Object 507 eCall requires the ability for the PSAP to acknowledge successful 508 receipt of an MSD sent by the IVS, and for the PSAP to request that 509 the IVS send an MSD (e.g., the call taker can initiate a request for 510 a new MSD to see if there have been changes in the vehicle's state, 511 e.g., location, direction, number of fastened seatbelts). 513 This document defines a block of metadata/control data as an XML 514 structure containing elements used for eCall and other related 515 emergency call systems and extension points. (This metadata/control 516 block is in effect a high-level protocol between the PSAP and IVS.) 517 When the PSAP sends a metadata/control block in response to data sent 518 by the IVS in a SIP request other than INFO (e.g., the MSD in the 519 initial INVITE), the metadata/control block is sent in the SIP 520 response to that request (e.g., the response to the INVITE request). 521 When the PSAP sends a control block in other circumstances (e.g., 522 mid-call), the control block is transmitted from the PSAP to the IVS 523 in a SIP INFO request within the established dialog. The IVS sends 524 the requested data (the MSD) in a new SIP INFO request (per 526 [RFC6086]). This mechanism flexibly allows the PSAP to send eCall- 527 specific data to the IVS and the IVS to respond. SIP INFO requests 528 are sent using an appropriate SIP INFO Package. See Section 6 for 529 more information on sending a metadata/control block within a SIP 530 message. See Section 14.9 for information about the use of SIP INFO 531 requests to carry data within an eCall. 533 When the IVS includes an unsolicited MSD in a SIP request (e.g., the 534 initial INVITE), the PSAP sends a metadata/control block indicating 535 successful/unsuccessful receipt of the MSD in the SIP response to the 536 request. This also informs the IVS that an NG-eCall is in operation. 537 If the IVS receives a SIP final response without the metadata/control 538 block, it indicates that the SIP dialog is not an NG-eCall (e.g., 539 some part of the call is being handled as a legacy call). When the 540 IVS sends a solicited MSD (e.g., in a SIP INFO request sent following 541 receipt of a SIP INFO request containing a metadata/control block 542 requesting an MSD), the PSAP does not send a metadata/control block 543 indicating successful or unsuccessful receipt of the MSD. (Normal 544 SIP retransmission handles non-receipt of requested data; note that, 545 per [RFC6086], a 200 OK response to a SIP INFO request indicates only 546 that the receiver has successfully received and accepted the SIP INFO 547 request, it says nothing about the acceptability of the payload.) If 548 the IVS receives a request to send an MSD but it is unable to do so 549 for any reason, the IVS sends a metadata/control object acknowledging 550 the request and containing "success=false" and "reason" set to an 551 appropriate code. 553 This provides flexibility to handle various circumstances. For 554 example, if a PSAP is unable to accept an eCall (e.g., due to 555 overload or too many calls from the same location), it can reject the 556 INVITE. Since a metadata/control object is also included in the SIP 557 response that rejects the call, the IVS knows if the PSAP received 558 the MSD, and can inform the vehicle occupants that the PSAP 559 successfully received the vehicle location and information but can't 560 talk to the occupants at that time. Especially for SIP response 561 codes that indicate an inability to conduct a call (as opposed to a 562 technical inability to process the request), the IVS can also 563 determine that the call was successful on a technical level (e.g., 564 not helpful to retry as circuit-switched). (Note that there could be 565 edge cases where the PSAP response is not received by the IVS, e.g., 566 if an intermediary sends a CANCEL, and an error response is forwarded 567 towards the IVS before the error response from the PSAP is received, 568 the response will be dropped, but these are unlikely to occur here.) 570 The metadata/control block is carried in the MIME type 'application/ 571 emergencyCallData.control+xml'. 573 The metadata/control block is designed for use with pan-European 574 eCall and also eCall-like systems (i.e., in other regions), and has 575 extension points. Note that eCall-like systems might define their 576 own vehicle data blocks, and so might need to register a new INFO 577 package to accommodate the new data MIME media type and the metadata/ 578 control object. 580 9.1. The Control Block 582 The control block is an XML data structure allowing for 583 acknowledgments, requests, and capabilities information. It is 584 carried in a body part with a specific MIME media type. Three 585 elements are defined for use within a control block: 587 ack Acknowledges receipt of data or a request. 589 capabilities Used in a control block sent from the IVS to the PSAP 590 (e.g., in the initial INVITE) to inform the PSAP of the 591 vehicle capabilities. Child elements contain all 592 actions and data types supported by the vehicle. It is 593 OPTIONAL for the IVS to send this block. Omitting the 594 block indicates that the IVS supports only the 595 mandatory functionality defined in this document. 597 request Used in a control block sent by the PSAP to the IVS, to 598 request the vehicle to perform an action. 600 The element indicates the object being acknowledged and reports 601 success or failure. 603 The element contains attributes to indicate the request and 604 to supply related information. The 'action' attribute is mandatory 605 and indicates the specific action. An IANA registry is created in 606 Section 14.8.1 to contain the allowed values. 608 The element has child elements to indicate 609 the actions supported by the IVS. 611 9.1.1. The element 613 The element acknowledges receipt of an eCall data object or 614 request. An element references the Content-ID of the object 615 being acknowledged. The PSAP MUST send an element 616 acknowledging receipt of an unsolicited MSD (e.g., sent by the IVS in 617 the INVITE); this element indicates if the PSAP considers the 618 MSD successfully received or not. An element is not sent for a 619 element. 621 The element has the following attributes: 623 9.1.1.1. Attributes of the element 625 The element has the following attributes: 627 Name: ref 628 Usage: Mandatory 629 Type: anyURI 630 Direction: Sent in either direction 631 Description: References the Content-ID of the body part being 632 acknowledged. 633 Example: 635 Name: received 636 Usage: Conditional: mandatory in an element sent by a PSAP 637 Type: Boolean 638 Direction: In this document, sent from the PSAP to the IVS 639 Description: Indicates if the referenced object was considered 640 successfully received or not. 641 Example: 643 9.1.1.2. Child Element of the element 645 For extensibility, the element has the following child element: 647 Name: actionResult 648 Usage: Optional 649 Direction: Sent from the IVS to the PSAP 650 Description: An element indicates the result of an 651 action (other than a successfully executed 'send-data' action). 652 The element contains an element for each 653 element that is not a successfully executed 'send-data' 654 action. The element has the following attributes: 656 Name: action 657 Usage: Mandatory 658 Type: token 659 Description: Contains the value of the 'action' attribute of the 660 element 662 Name: success 663 Usage: Mandatory 664 Type: Boolean 665 Description: Indicates if the action was successfully 666 accomplished 668 Name: reason 669 Usage: Conditional 670 Type: token 671 Description: Used when 'success' is "false", this attribute 672 contains a reason code for a failure. A registry for reason 673 codes is defined in Section 14.8.2. The initial values are: 674 damaged (required components are damaged), data-unsupported 675 (the data item referenced in a 'send-data' request is not 676 supported), security-failure (the authenticity of the request 677 or the authority of the requestor could not be verified), 678 unable (a generic error for use when no other code is 679 appropriate), and unsupported (the 'action' value is not 680 supported). 682 Name: details 683 Usage: optional 684 Type: string 685 Description: Contains further explanation of the circumstances of 686 a success or failure. The contents are implementation-specific 687 and human-readable. 689 9.1.1.3. Ack Examples 691 692 696 698 700 Figure 3: Ack Example from PSAP to IVS 702 9.1.2. The element 704 The element is transmitted by the IVS to indicate to 705 the PSAP its capabilities. No attributes for this element are 706 currently defined. The following child elements are defined: 708 9.1.2.1. Child Element of the element 710 The element has the following child element: 712 Name: request 713 Usage: Mandatory 714 Description: The element contains a child 715 element per action supported by the vehicle. 717 Example: 719 721 723 725 It is OPTIONAL for the IVS to support the element. If 726 the IVS does not send a element, this indicates that 727 the only action supported by the IVS is 'send-data' with 728 'datatype' set to 'eCall.MSD'. 730 9.1.2.2. Capabilities Example 732 733 737 738 739 741 743 Figure 4: Capabilities Example 745 9.1.3. The element 747 A element appears one or more times on its own or as a 748 child of a element. It allows the PSAP to request 749 that the IVS perform an action. The only action that MUST be 750 supported is to send an MSD. The following attributes and child 751 elements are defined: 753 9.1.3.1. Attributes of the element 755 The element has the following attributes: 757 Name: action 758 Usage: Mandatory 759 Type: token 760 Direction: Sent in either direction 761 Description: Identifies the action that the vehicle is requested to 762 perform (in a element within a element, 763 indicates an action that the vehicle is capable of performing). 764 An IANA registry is established in Section 14.8.1 to contain the 765 allowed values. 766 Example: action="send-data" 768 Name: int-id 769 Usage: Conditional 770 Type: int 771 Direction: Sent in either direction 772 Description: Defined for extensibility. Documents that make use of 773 it are expected to explain when it is required and how it is used. 774 Example: int-id="3" 776 Name: persistence 777 Usage: Optional 778 Type: xs:duration 779 Direction: Sent in either direction 780 Description: Defined for extensibility. Specifies how long to carry 781 on the specified action. If absent, the default is for the 782 duration of the call. 783 Example: persistence="PT1H" 785 Name: datatype 786 Usage: Conditional 787 Type: token 788 Direction: Sent in either direction 789 Description: Mandatory with a "send-data" action within a 790 element that is not within a element. Specifies 791 the data block that the IVS is requested to transmit, using the 792 same identifier as in the 'purpose' attribute set in a Call-Info 793 header field to point to the data block. Permitted values are 794 contained in the 'Emergency Call Data Types' IANA registry 795 established in [RFC7852]. Only the "eCall.MSD" value is mandatory 796 to support. 797 Example: datatype="eCall.MSD" 799 Name: supported-values 800 Usage: Conditional 801 Type: string 802 Direction: Sent from the IVS to the PSAP 803 Description: Defined for extensibility. Used in a element 804 that is a child of a element, this attribute lists 805 all supported values of the action type. Permitted values depend 806 on the action value. Multiple values are separated with a 807 semicolon. Documents that make use of it are expected to explain 808 when it is required, the permitted values, and how it is used. 810 Name: requested-state 811 Usage: Conditional 812 Type: token 813 Direction: Sent from the PSAP to the IVS 814 Description: Defined for extension. Indicates the requested state 815 of an element associated with the request type. Permitted values 816 depend on the request type. Documents that make use of it are 817 expected to explain when it is required, the permitted values, and 818 how it is used. 820 Name: element-id 821 Usage: Conditional 822 Type: token 823 Direction: Sent from the PSAP to the IVS 824 Description: Defined for extension. Identifies the element to be 825 acted on. Permitted values depend on the request type. Documents 826 that make use of it are expected to explain when it is required, 827 the permitted values, and how it is used. 829 9.1.3.2. Request Example 831 832 836 838 840 Figure 5: Request Example 842 10. Examples 844 Figure 6 illustrates an eCall. The call uses the request URI 845 'urn:service:sos.ecall.automatic' service URN and is recognized as an 846 eCall, and further as one that was invoked automatically by the IVS 847 due to a crash or other serious incident. In this example, the 848 originating network routes the call to an ESInet which routes the 849 call to the appropriate NG-eCall capable PSAP. The emergency call is 850 received by the ESInet's Emergency Services Routing Proxy (ESRP), as 851 the entry point into the ESInet. The ESRP routes the call to a PSAP, 852 where it is received by a call taker. In deployments where there is 853 no ESInet, the originating network routes the call directly to the 854 appropriate NG-eCall capable PSAP, an illustration of which would be 855 identical to the one below except without an ESInet or ESRP. 857 +------------+ +---------------------------------------+ 858 | | | +-------+ | 859 | | | | PSAP2 | | 860 | | | +-------+ | 861 | | | | 862 | | | +------+ +-------+ | 863 Vehicle-->| |--+->| ESRP |---->| PSAP1 |--> Call-Taker | 864 | | | +------+ +-------+ | 865 | | | | 866 | | | +-------+ | 867 | | | | PSAP3 | | 868 | Originating| | +-------+ | 869 | Mobile | | | 870 | Network | | ESInet | 871 +------------+ +---------------------------------------+ 873 Figure 6: Example of NG-eCall Message Flow 875 Figure 7 illustrates an eCall call flow with a mid-call PSAP request 876 for an updated MSD. The call flow shows the IVS initiating an 877 emergency call, including the MSD in the INVITE. The PSAP includes 878 in the 200 OK response a metadata/control object acknowledging 879 receipt of the MSD. During the call, the PSAP sends a request for an 880 MSD in an INFO request. The IVS sends the requested MSD in a new 881 INFO request. 883 IVS PSAP 884 |(1) INVITE (eCall MSD) | 885 |------------------------------------------->| 886 | | 887 |(2) 200 OK (eCall metadata [ack MSD]) | 888 |<-------------------------------------------| 889 | | 890 |(3) start media stream(s) | 891 |............................................| 892 | | 893 |(4) INFO (eCall metadata [request MSD]) | 894 |<-------------------------------------------| 895 | | 896 |(5) 200 OK | 897 |------------------------------------------->| 898 | | 899 |(6) INFO (eCall MSD) | 900 |------------------------------------------->| 901 | | 902 |(7) 200 OK | 903 |<-------------------------------------------| 904 | | 905 |(8) BYE | 906 |<-------------------------------------------| 907 | | 908 |(9) end media streams | 909 |............................................| 910 | | 911 |(10) 200 OK | 912 |------------------------------------------->| 914 Figure 7: NG-eCall Call Flow Illustration 916 The example, shown in Figure 8, illustrates a SIP eCall INVITE 917 request containing an MSD. For simplicity, the example does not show 918 all SIP headers, nor the SDP contents, nor does it show any 919 additional data blocks added by the IVS or the originating mobile 920 network. Because the MSD is encoded in ASN.1 PER, which is a binary 921 encoding, its contents cannot be included in a text document. 923 INVITE urn:service:sos.ecall.automatic SIP/2.0 924 To: urn:service:sos.ecall.automatic 925 From: ;tag=9fxced76sl 926 Call-ID: 3848276298220188511@atlanta.example.com 927 Geolocation: 928 Geolocation-Routing: no 929 Call-Info: ; 930 purpose=emergencyCallData.eCall.MSD 931 Accept: application/sdp, application/pidf+xml, 932 application/emergencyCallData.control+xml 933 CSeq: 31862 INVITE 934 Recv-Info: emergencyCallData.eCall.MSD 935 Allow: INVITE, ACK, PRACK, INFO, OPTIONS, CANCEL, REFER, BYE, 936 SUBSCRIBE, NOTIFY, UPDATE 937 Content-Type: multipart/mixed; boundary=boundary1 938 Content-Length: ... 940 --boundary1 941 Content-Type: application/sdp 943 ...Session Description Protocol (SDP) goes here... 945 --boundary1 946 Content-Type: application/pidf+xml 947 Content-ID: 948 Content-Disposition: by-reference;handling=optional 950 ...PIDF-LO goes in here 952 --boundary1 953 Content-Type: application/emergencyCallData.eCall.MSD+per 954 Content-ID: <1234567890@atlanta.example.com> 955 Content-Disposition: by-reference;handling=optional 957 ...MSD in ASN.1 PER encoding goes here... 959 --boundary1-- 961 Figure 8: SIP NG-eCall INVITE 963 Continuing the example, Figure 9 illustrates a SIP 200 OK response to 964 the INVITE request of Figure 8, containing a control block 965 acknowledging successful receipt of the eCall MSD. (For simplicity, 966 the example does not show all SIP headers.) 967 SIP/2.0 200 OK 968 To: urn:service:sos.ecall.automatic;tag=8gydfe65t0 969 From: ;tag=9fxced76sl 970 Call-ID: 3848276298220188511@atlanta.example.com 971 Call-Info: ; 972 purpose=emergencyCallData.control 973 Accept: application/sdp, application/pidf+xml, 974 application/emergencyCallData.control+xml, 975 application/emergencyCallData.eCall.MSD+per 976 CSeq: 31862 INVITE 977 Recv-Info: emergencyCallData.eCall.MSD 978 Allow: INVITE, ACK, PRACK, INFO, OPTIONS, CANCEL, REFER, BYE, 979 SUBSCRIBE, NOTIFY, UPDATE 980 Content-Type: multipart/mixed; boundary=boundaryX 981 Content-Length: ... 983 --boundaryX 984 Content-Type: application/sdp 986 ...Session Description Protocol (SDP) goes here... 988 --boundaryX 989 Content-Type: application/emergencyCallData.control+xml 990 Content-ID: <2345678901@atlanta.example.com> 991 Content-Disposition: by-reference 993 994 998 999 1001 --boundaryX-- 1003 Figure 9: 200 OK response to INVITE 1005 Figure 10 illustrates a SIP INFO request containing a metadata/ 1006 control block requesting an eCall MSD. (For simplicity, the example 1007 does not show all SIP headers.) 1008 INFO sip:+13145551111@example.com SIP/2.0 1009 To: ;tag=9fxced76sl 1010 From: Exemplar PSAP ;tag=8gydfe65t0 1011 Call-ID: 3848276298220188511@atlanta.example.com 1012 Call-Info: ; 1013 purpose=emergencyCallData.control 1014 CSeq: 41862 INFO 1015 Info-Package: emergencyCallData.eCall.MSD 1016 Allow: INVITE, ACK, PRACK, INFO, OPTIONS, CANCEL, REFER, BYE, 1017 SUBSCRIBE, NOTIFY, UPDATE 1018 Content-Type: multipart/mixed; boundary=boundaryZZZ 1019 Content-Dispositio: Info-Package 1020 Content-Length: ... 1022 --boundaryZZZ 1023 Content-Disposition: by-reference 1024 Content-Type: application/emergencyCallData.control+xml 1025 Content-ID: <3456789012@atlanta.example.com> 1027 1028 1032 1034 1035 --boundaryZZZ-- 1037 Figure 10: INFO requesting MSD 1039 Figure 11 illustrates a SIP INFO request containing an MSD. For 1040 simplicity, the example does not show all SIP headers. Because the 1041 MSD is encoded in ASN.1 PER, which is a binary encoding, its contents 1042 cannot be included in a text document. 1044 INFO urn:service:sos.ecall.automatic SIP/2.0 1045 To: urn:service:sos.ecall.automatic;tag=8gydfe65t0 1046 From: ;tag=9fxced76sl 1047 Call-ID: 3848276298220188511@atlanta.example.com 1048 Call-Info: ; 1049 purpose=emergencyCallData.eCall.MSD 1050 CSeq: 51862 INFO 1051 Info-Package: emergencyCallData.eCall.MSD 1052 Allow: INVITE, ACK, PRACK, INFO, OPTIONS, CANCEL, REFER, BYE, 1053 SUBSCRIBE, NOTIFY, UPDATE 1054 Content-Type: multipart/mixed; boundary=boundaryLine 1055 Content-Disposition: Info-Package 1056 Content-Length: ... 1058 --boundaryLine 1059 Content-Type: application/emergencyCallData.eCall.MSD+per 1060 Content-ID: <4567890123@atlanta.example.com> 1061 Content-Disposition: by-reference 1063 ...MSD in ASN.1 PER encoding goes here... 1065 --boundaryLine-- 1067 Figure 11: INFO containing MSD 1069 11. Security Considerations 1071 The security considerations described in [RFC5069] (on marking and 1072 routing emergency calls) apply here. 1074 In addition to any network-provided location (which might be 1075 determined solely by the network, or in cooperation with or possibly 1076 entirely by the originating device), an eCall carries an IVS-supplied 1077 location within the MSD. This is likely to be useful to the PSAP, 1078 especially when no network-provided location is included, or when the 1079 two locations are independently determined. Even in situations where 1080 the network-supplied location is limited to the cell site, this can 1081 be useful as a sanity check on the device-supplied location contained 1082 in the MSD. 1084 The document [RFC7378] discusses trust issues regarding location 1085 provided by or determined in cooperation with end devices. 1087 Security considerations specific to the mechanism by which the PSAP 1088 sends acknowledgments and requests to the vehicle are discussed in 1089 the "Security Considerations" block of Section 14.4. Note that an 1090 attacker that has access to and is capable of generating a response 1091 to the initial INVITE request could generate a 600 (Busy Everywhere), 1092 486 (Busy Here), or 603 (Decline) response that includes a metadata/ 1093 control object containing a reference to the MSD in the initial 1094 INVITE and a "received=true" field, which could result in the IVS 1095 perceiving the PSAP to be overloaded and hence not attempting to 1096 reinitiate the call. The risk can be mitigated as discussed in the 1097 "Security Considerations" block of Section 14.4. 1099 Data received from external sources inherently carries implementation 1100 risks. For example, depending on the platform, buffer overflows can 1101 introduce remote code execution vulnerabilities, null characters can 1102 corrupt strings, numeric values used for internal calculations can 1103 result in underflow/overflow errors, malformed XML objects can expose 1104 parsing bugs, etc. Implementations need to be cognizant of the 1105 potential risks, observe best practices (which might include 1106 sufficiently capable static code analysis, fuzz testing, component 1107 isolation, avoiding use of unsafe coding techniques, third-party 1108 attack tests, signed software, over-the-air updates, etc.), and have 1109 multiple levels of protection. Implementors need to be aware that, 1110 potentially, the data objects described here and elsewhere (including 1111 the MSD and metadata/control objects) might be malformed, might 1112 contain unexpected characters, excessively long attribute values, 1113 elements, etc. 1115 The security considerations discussed in [RFC7852] apply here (see 1116 especially the discussion of TLS, TLS versions, cipher suites, and 1117 PKI). 1119 When vehicle data or control/metadata is contained in a signed or 1120 encrypted body part, the enclosing multipart (e.g., multipart/signed 1121 or multipart/encrypted) has the same Content-ID as the enclosed data 1122 part. This allows an entity to identify and access the data blocks 1123 it is interested in without having to dive deeply into the message 1124 structure or decrypt parts it is not interested in. (The 'purpose' 1125 parameter in a Call-Info header field identifies the data and 1126 contains a CID URL pointing to the data block in the body, which has 1127 a matching Content-ID body part header field). 1129 12. Privacy Considerations 1131 The privacy considerations discussed in [RFC7852] apply here. The 1132 MSD carries some identifying and personal information (mostly about 1133 the vehicle and less about the owner), as well as location 1134 information, and so needs to be protected against unauthorized 1135 disclosure. Local regulations may impose additional privacy 1136 protection requirements. 1138 Privacy considerations specific to the data structure containing 1139 vehicle information are discussed in the "Security Considerations" 1140 block of Section 14.3. 1142 Privacy considerations specific to the mechanism by which the PSAP 1143 sends acknowledgments and requests to the vehicle are discussed in 1144 the "Security Considerations" block of Section 14.4. 1146 13. XML Schema 1148 This section defines an XML schema for the control block. The text 1149 description of the control block in Section 9.1 is normative and 1150 supersedes any conflicting aspect of this schema. 1152 1153 1161 1163 1166 1167 1168 1169 1170 1172 1173 1174 1177 1178 1179 1180 1181 1183 1184 1185 1186 1187 1189 1190 1193 1196 1198 1199 1200 conditionally mandatory 1201 when @success="false" 1202 to indicate reason code 1203 for a failure 1204 1205 1206 1207 1209 1211 1212 1213 1216 1217 1220 1222 1223 1224 1225 1227 1228 1229 1230 1231 1235 1238 1239 1240 1241 1242 1244 1245 1246 1247 1248 1251 1252 1254 1255 1257 1258 1260 1261 1263 1264 1265 1266 1268 1270 Figure 12: Control Block Schema 1272 14. IANA Considerations 1274 14.1. The EmergencyCallData Media Subtree 1276 This document establishes the "EmergencyCallData" media (MIME) 1277 subtype tree, a new media subtree rooted at "application/ 1278 EmergencyCallData". This subtree is used only for content associated 1279 with emergency communications. New subtypes in this subtree follow 1280 the rules specified in Section 3.1 of [RFC6838], with the additional 1281 restriction that the standards-related organization MUST be 1282 responsible for some aspect of emergency communications. 1284 This subtree initially contains the following subtypes (defined here 1285 or in [RFC7852]): 1287 emergencyCallData.control+xml 1288 EmergencyCallData.Comment+xml 1289 EmergencyCallData.DeviceInfo+xml 1290 EmergencyCallData.MSD+per 1291 EmergencyCallData.ProviderInfo+xml 1292 EmergencyCallData.ServiceInfo+xml 1293 EmergencyCallData.SubscriberInfo+xml 1295 14.2. Service URN Registrations 1297 IANA is requested to register the URN 'urn:service:sos.ecall' under 1298 the sub-services 'sos' registry defined in Section 4.2 of [RFC5031]. 1300 This service requests resources associated with an emergency call 1301 placed by an in-vehicle system, carrying a standardized set of data 1302 related to the vehicle and incident. Two sub-services are registered 1303 as well: 1305 urn:service:sos.ecall.manual 1307 Used with an eCall invoked due to manual interaction by a vehicle 1308 occupant. 1310 urn:service:sos.ecall.automatic 1312 Used with an eCall invoked automatically, for example, due to a 1313 crash or other serious incident. 1315 IANA is also requested to register the URN 1316 'urn:service:test.sos.ecall' under the sub-service 'test' registry 1317 defined in Setcion 17.2 of [RFC6881]. This service requests 1318 resources associated with a test (non-emergency) call placed by an 1319 in-vehicle system. See Section 8 for more information on the test 1320 eCall request URN. 1322 14.3. MIME Media Type Registration for 'application/ 1323 emergencyCallData.eCall.MSD+per' 1325 IANA is requested to add application/emergencyCallData.eCall.MSD+per 1326 as a MIME media type, with a reference to this document, in 1327 accordance to the procedures of RFC 6838 [RFC6838] and guidelines in 1328 RFC 7303 [RFC7303]. 1330 MIME media type name: application 1332 MIME subtype name: emergencyCallData.eCall.MSD+per 1334 Mandatory parameters: none 1336 Optional parameters: none 1338 Encoding scheme: binary 1340 Encoding considerations: Uses ASN.1 PER, which is a binary 1341 encoding; when transported in SIP, binary content transfer 1342 encoding is used. 1344 Security considerations: This media type is designed to carry 1345 vehicle and incident-related data during an emergency call. This 1346 data contains personal information including vehicle VIN, 1347 location, direction, etc. Appropriate precautions need to be 1348 taken to limit unauthorized access, inappropriate disclosure to 1349 third parties, and eavesdropping of this information. Sections 9 1350 and Section 10 of [RFC7852] contain more discussion. 1352 Interoperability considerations: None 1354 Published specification: Annex A of EN 15722 [msd] 1356 Applications which use this media type: Pan-European eCall 1357 compliant systems 1359 Additional information: None 1361 Magic Number: None 1363 File Extension: None 1365 Macintosh file type code: 'BINA' 1367 Person and email address for further information: Randall Gellens, 1368 rg+ietf@randy.pensive.org 1370 Intended usage: LIMITED USE 1372 Author: The MSD specification was produced by the European 1373 Committee For Standardization (CEN). For contact information, 1374 please see . 1376 Change controller: The European Committee For Standardization 1377 (CEN) 1379 14.4. MIME Media Type Registration for 'application/ 1380 emergencyCallData.control+xml' 1382 IANA is requested to add application/emergencyCallData.control+xml as 1383 a MIME media type, with a reference to this document, in accordance 1384 to the procedures of RFC 6838 [RFC6838] and guidelines in RFC 7303 1385 [RFC7303]. 1387 MIME media type name: application 1389 MIME subtype name: emergencyCallData.control+xml 1391 Mandatory parameters: none 1393 Optional parameters: charset 1395 Indicates the character encoding of the XML content. 1397 Encoding considerations: Uses XML, which can employ 8-bit 1398 characters, depending on the character encoding used. See 1399 Section 3.2 of RFC 7303 [RFC7303]. 1401 Security considerations: 1403 This media type carries metadata and control information and 1404 requests, such as from a Public Safety Answering Point (PSAP) 1405 to an In-Vehicle System (IVS) during an emergency call. 1407 Metadata (such as an acknowledgment that data sent by the IVS 1408 to the PSAP was successfully received) has limited privacy and 1409 security implications. Control information (such as requests 1410 from the PSAP that the vehicle perform an action) has some 1411 privacy and security implications. The privacy concern arises 1412 from the ability to request the vehicle to transmit a data set, 1413 which as described in Section 14.3, can contain personal 1414 information. The security concern is the ability to request 1415 the vehicle to perform an action. Control information needs to 1416 originate only from a PSAP or other emergency services 1417 provider, and not be modified en-route. The level of integrity 1418 of the cellular network over which the emergency call is placed 1419 is a consideration: when the IVS initiates an eCall over a 1420 cellular network, in most cases it relies on the MNO to route 1421 the call to a PSAP. (Calls placed using other means, such as 1422 Wi-Fi or over-the-top services, generally incur somewhat higher 1423 levels of risk than calls placed "natively" using cellular 1424 networks.) A call-back from a PSAP merits additional 1425 consideration, since current mechanisms are not ideal for 1426 verifying that such a call is indeed a call-back from a PSAP in 1427 response to an emergency call placed by the IVS. See the 1428 discussion in Section 11 and the PSAP Callback document 1429 [RFC7090]. 1431 Sections 7 and Section 8 of [RFC7852] contain more discussion. 1433 Interoperability considerations: None 1435 Published specification: This document 1437 Applications which use this media type: Pan-European eCall 1438 compliant systems 1440 Additional information: None 1442 Magic Number: None 1444 File Extension: .xml 1446 Macintosh file type code: 'TEXT' 1448 Person and email address for further information: Randall Gellens, 1449 rg+ietf@randy.pensive.org 1451 Intended usage: LIMITED USE 1453 Author: The IETF ECRIT WG. 1455 Change controller: The IETF ECRIT WG. 1457 14.5. Registration of the 'eCall.MSD' entry in the Emergency Call 1458 Additional Data Types registry 1460 This specification requests IANA to add the 'eCall.MSD' entry to the 1461 Emergency Call Additional Data Types registry, with a reference to 1462 this document; the 'Data About' value is 'The Call'. 1464 14.6. Registration of the 'control' entry in the Emergency Call 1465 Additional Data Types registry 1467 This specification requests IANA to add the 'control' entry to the 1468 Emergency Call Additional Data Types registry, with a reference to 1469 this document; the 'Data About' value is 'The Call'. 1471 14.7. URN Sub-Namespace Registration 1473 14.7.1. Registration for urn:ietf:params:xml:ns:eCall 1475 This section registers a new XML namespace, as per the guidelines in 1476 RFC 3688 [RFC3688]. 1478 URI: urn:ietf:params:xml:ns:eCall 1480 Registrant Contact: IETF, ECRIT working group, , as 1481 delegated by the IESG . 1483 XML: 1485 BEGIN 1486 1487 1489 1490 1491 1493 Namespace for eCall Data 1494 1495 1496

Namespace for eCall Data

1497

See [TBD: This document].

1498 1499 1500 END 1502 14.7.2. Registration for urn:ietf:params:xml:ns:control 1504 This section registers a new XML namespace, as per the guidelines in 1505 RFC 3688 [RFC3688]. 1507 URI: urn:ietf:params:xml:ns:control 1509 Registrant Contact: IETF, ECRIT working group, , as 1510 delegated by the IESG . 1512 XML: 1514 BEGIN 1515 1516 1518 1519 1520 1522 Namespace for eCall Data: 1523 Control Block 1524 1525 1526

Namespace for eCall Data

1527

Control Block

1528

See [TBD: This document].

1529 1530 1531 END 1533 14.8. Registry Creation 1535 This document creates a new registry called "Emergency Call Metadata/ 1536 Control Data". The following sub-registries are created for this 1537 registry. 1539 14.8.1. Emergency Call Action Registry 1541 This document creates a new sub-registry called "Emergency Call 1542 Action". As defined in [RFC5226], this registry operates under 1543 "Expert Review" rules. The expert should determine that the proposed 1544 action is within the purview of a vehicle, is sufficiently 1545 distinguishable from other actions, and the action is clearly and 1546 fully described. In most cases, a published and stable document is 1547 referenced for the description of the action. 1549 The content of this registry includes: 1551 Name: The identifier to be used in the 'action' attribute of a 1552 control element. 1554 Description: A description of the action. In most cases this will 1555 be a reference to a published and stable document. The 1556 description MUST specify if any attributes or child elements are 1557 optional or mandatory, and describe the action to be taken by the 1558 vehicle. 1560 The initial set of values is listed in Table 2. 1562 +-----------+--------------------------------------+ 1563 | Name | Description | 1564 +-----------+--------------------------------------+ 1565 | send-data | See Section 9.1.3.1 of this document | 1566 +-----------+--------------------------------------+ 1568 Table 2: Emergency Call Action Registry Initial Values 1570 14.8.2. Emergency Call Action Failure Reason Registry 1572 This document creates a new sub-registry called "Emergency Call 1573 Action Failure Reason" which contains values for the 'reason' 1574 attribute of the element. As defined in [RFC5226], 1575 this registry operates under "Expert Review" rules. The expert 1576 should determine that the proposed reason is sufficiently 1577 distinguishable from other reasons and that the proposed description 1578 is understandable and correctly worded. 1580 The content of this registry includes: 1582 ID: A short string identifying the reason, for use in the 'reason' 1583 attribute of an element. 1585 Description: A description of the reason. 1587 The initial set of values is listed in Table 3. 1589 +------------------+------------------------------------------------+ 1590 | ID | Description | 1591 +------------------+------------------------------------------------+ 1592 | damaged | Required components are damaged. | 1593 | | | 1594 | data-unsupported | The data item referenced in a 'send-data' | 1595 | | request is not supported. | 1596 | | | 1597 | security-failure | The authenticity of the request or the | 1598 | | authority of the requestor could not be | 1599 | | verified. | 1600 | | | 1601 | unable | The action could not be accomplished (a | 1602 | | generic error for use when no other code is | 1603 | | appropriate). | 1604 | | | 1605 | unsupported | The 'action' value is not supported. | 1606 +------------------+------------------------------------------------+ 1608 Table 3: Emergency Call Action Failure Reason Registry Initial Values 1610 14.9. The emergencyCallData.eCall.MSD INFO package 1612 This document registers the 'emergencyCallData.eCall.MSD' INFO 1613 package. 1615 Both endpoints (the IVS and the PSAP equipment) include 1616 'emergencyCallData.eCall.MSD' in a Recv-Info header field per 1617 [RFC6086] to indicate ability to receive INFO requests carrying data 1618 as described here. 1620 Support for the 'emergencyCallData.eCall.MSD' INFO package indicates 1621 the ability to receive eCall related body parts as specified in [TBD: 1622 THIS DOCUMENT]. 1624 An INFO request message carrying body parts related to an emergency 1625 call as described in [TBD: THIS DOCUMENT] has an Info-Package header 1626 field set to 'emergencyCallData.eCall.MSD' per [RFC6086]. 1628 The requirements of Section 10 of [RFC6086] are addressed in the 1629 following sections. 1631 14.9.1. Overall Description 1633 This section describes "what type of information is carried in INFO 1634 requests associated with the Info Package, and for what types of 1635 applications and functionalities UAs can use the Info Package." 1637 INFO requests associated with the emergencyCallData.eCall.MSD INFO 1638 package carry data associated with emergency calls as defined in 1639 [TBD: THIS DOCUMENT]. The application is vehicle-initiated emergency 1640 calls established using SIP. The functionality is to carry vehicle 1641 data and metadata/control information between vehicles and PSAPs. 1642 Refer to [TBD: THIS DOCUMENT] for more information. 1644 14.9.2. Applicability 1646 This section describes "why the Info Package mechanism, rather than 1647 some other mechanism, has been chosen for the specific use-case...." 1649 The use of the SIP INFO method is based on an analysis of the 1650 requirements against the intent and effects of the INFO method versus 1651 other approaches (which included the SIP MESSAGE method, the SIP 1652 OPTIONS method, the SIP re-INVITE method, media plane transport, and 1653 non-SIP protocols). In particular, the transport of emergency call 1654 data blocks occurs within a SIP emergency dialog, per Section 6, and 1655 is normally carried in the initial INVITE request and response; the 1656 use of the SIP INFO method only occurs when emergency-call-related 1657 data needs to be sent mid-call. While the SIP MESSAGE method could 1658 be used, it is not tied to a SIP dialog as is the SIP INFO method and 1659 thus might not be associated with the dialog. Either the SIP OPTIONS 1660 or re-INVITE methods could also be used, but is seen as less clean 1661 than the SIP INFO method. The SIP SUBSCRIBE/NOTIFY method could be 1662 coerced into service, but the semantics are not a good fit, e.g., the 1663 subscribe/notify mechanism provides one-way communication consisting 1664 of (often multiple) notifications from notifier to subscriber 1665 indicating that certain events in notifier have occurred, whereas 1666 what's needed here is two-way communication of data related to the 1667 emergency dialog. Use of the media plane mechanisms was discounted 1668 because the number of messages needing to be exchanged in a dialog is 1669 normally zero or very few, and the size of the data is likewise very 1670 small. The overhead caused by user plane setup (e.g., to use MSRP as 1671 transport) would be disproportionately large. 1673 Based on the analyses, the SIP INFO method was chosen to provide for 1674 mid-call data transport. 1676 14.9.3. Info Package Name 1678 The info package name is emergencyCallData.eCall.MSD 1680 14.9.4. Info Package Parameters 1682 None 1684 14.9.5. SIP Option-Tags 1686 None 1688 14.9.6. INFO Request Body Parts 1690 The body for an emergencyCallData.eCall.MSD info package is a 1691 multipart (normally multipart/mixed) body containing zero or one 1692 application/emergencyCallData.eCall.MSD+per part (containing an MSD) 1693 and zero or more application/emergencyCallData.control+xml 1694 (containing a metadata/control object) parts. At least one MSD or 1695 metadata/control body part is expected; the behavior upon receiving 1696 an INFO request with neither is undefined. 1698 The body parts are sent per [RFC6086], and in addition, to align with 1699 with how these body parts are sent in SIP messages other than INFO 1700 requests, each associated body part is referenced by a Call-Info 1701 header field at the top level of the SIP message. The body part has 1702 a Content-Disposition header field set to "By-Reference". 1704 An MSD or metadata/control block is always enclosed in a multipart 1705 body part (even if it would otherwise be the only body part in the 1706 SIP message), since as of the date of this document, the use of 1707 Content-ID as a SIP header field is not defined (while it is defined 1708 for use as a MIME header field). The innermost multipart that 1709 contains only body parts associated with the INFO package has a 1710 Content-Disposition value of Info-Package. 1712 See [TBD: THIS DOCUMENT] for more information. 1714 14.9.7. Info Package Usage Restrictions 1716 Usage is limited to vehicle-initiated emergency calls as defined in 1717 [TBD: THIS DOCUMENT]. 1719 14.9.8. Rate of INFO Requests 1721 The SIP INFO request is used within an established emergency call 1722 dialog for the PSAP to request the IVS to send an updated MSD, and 1723 for the IVS to send a requested MSD. Because this is normally done 1724 only on manual request of the PSAP call taker (who suspects some 1725 aspect of the vehicle state has changed), the rate of SIP INFO 1726 requests associated with the emergencyCallData.eCall.MSD info package 1727 is normally quite low (most dialogs are likely to contain zero INFO 1728 requests, while others might carry an occasional request). 1730 14.9.9. Info Package Security Considerations 1732 The MIME media type registrations specified for use with this INFO 1733 package (Section 14.3 and Section 14.4) contain a discussion of the 1734 security and/or privacy considerations specific to that data block. 1735 The "Security Considerations" and "Privacy Considerations" sections 1736 of [TBD: THIS DOCUMENT] discuss security and privacy considerations 1737 of the data carried in eCalls. 1739 14.9.10. Implementation Details 1741 See [TBD: THIS DOCUMENT] for protocol details. 1743 14.9.11. Examples 1745 See [TBD: THIS DOCUMENT] for protocol examples. 1747 15. Contributors 1749 Brian Rosen was a co-author of the original document upon which this 1750 document is based. 1752 16. Acknowledgements 1754 We would like to thank Bob Williams and Ban Al-Bakri for their 1755 feedback and suggestion; Rex Buddenberg, Lena Chaponniere, Alissa 1756 Cooper, Keith Drage, Stephen Edge, Wes George, Allison Mankin, Ivo 1757 Sedlacek, and James Winterbottom for their review and comments; 1758 Robert Sparks and Paul Kyzivat for their help with the SIP 1759 mechanisms; Mark Baker and Ned Freed for their help with the media 1760 subtype registration issue. We would like to thank Michael Montag, 1761 Arnoud van Wijk, Gunnar Hellstrom, and Ulrich Dietz for their help 1762 with the original document upon which this document is based. 1763 Christer Holmberg deserves special mention for his many detailed 1764 reviews. 1766 17. Changes from Previous Versions 1768 RFC Editor: Please remove this section prior to publication. 1770 17.1. Changes from draft-ietf-19 to draft-ietf-20 1772 o Fixed various nits 1774 17.2. Changes from draft-ietf-18 to draft-ietf-19 1776 o Added additional text to "Rate of Info Requests" 1777 o Added additional text to "Security Considerations" 1778 o Further corrected "content type" to "media type" 1780 17.3. Changes from draft-ietf-17 to draft-ietf-18 1782 o Added reference to 3GPP TS24.229 1783 o Clarified that an INFO request is expected to have at least one 1784 MSD or metadata/control body part 1785 o Fixed minor errors in examples 1786 o Corrected "content type" to "media type" 1787 o Deleted "xsi:schemaLocation" from examples 1789 17.4. Changes from draft-ietf-16 to draft-ietf-17 1791 o Clarify Content-Disposition value in INFO requests 1793 17.5. Changes from draft-ietf-15 to draft-ietf-16 1795 o Various clarifications and simplifications 1796 o Added reference to 3GPP 23.167 1798 17.6. Changes from draft-ietf-14 to draft-ietf-15 1800 o eCall body parts now always sent enclosed in multipart (even if 1801 only body part in SIP message) and hence always have a Content- 1802 Disposition of By-Reference 1803 o Fixed errors in attribute directionality text 1804 o Fixed typos. 1806 17.7. Changes from draft-ietf-13 to draft-ietf-14 1808 o Added text to the IANA Considerations to formalize the 1809 EmergencyCallData media subtree 1810 o Fixed some typos 1812 17.8. Changes from draft-ietf-12 to draft-ietf-13 1814 o Clarifications suggested by Christer 1815 o Corrections to Content-Disposition text and examples as suggested 1816 by Paul Kyzivat 1817 o Clarifications to Content-Disposition text and examples to clarify 1818 that handling=optional is only used in the initial INVITE 1820 17.9. Changes from draft-ietf-11 to draft-ietf-12 1822 o Fixed errors in examples found by Dale 1823 o Removed enclosing sub-section of INFO package registration section 1824 o Added text per Christer and Dale's suggestions that the MSD and 1825 metadata/control blocks are sent in INFO with a Call-Info header 1826 field referencing them 1827 o Deleted Call Routing section (7.1) in favor of a statement that 1828 call routing is outside the scope of the document 1829 o Other text changes per comments received from Christer and Ivo. 1831 17.10. Changes from draft-ietf-09 to draft-ietf-11 1833 o Renamed INFO package to emergencyCallData.eCall.MSD 1834 o Changed INFO package to only permit MSD and metadata/control MIME 1835 types 1836 o Moved element back from car-crash but made it 1837 OPTIONAL 1838 o Moved other extension points back from car-crash so that extension 1839 points are in base spec (and also to get XML schema to compile) 1840 o Text changes for clarification. 1842 17.11. Changes from draft-ietf-08 to draft-ietf-09 1844 o Created a new "Data Transport" section that describes how the MSD 1845 and metadata/control blocks are attached, and then referred to 1846 that section rather than repeat the information about the CID and 1847 Call-Info and so forth, which means most references to the 1848 additional-data draft have now been deleted 1849 o Mentioned edge cases where a PSAP response to INVITE isn't 1850 received by the IVS 1851 o Reworded description of which status codes are used when a PSAP 1852 wishes to reject a call but inform the vehicle occupants that it 1853 is aware of the situation to be more definite 1854 o Added examples showing INFO 1855 o Added references for eCall test call requirement 1856 o Described meaning of eCall URNs in Section 8 as well as in IANA 1857 registration 1859 17.12. Changes from draft-ietf-07 to draft-ietf-08 1861 o eCall MSD now encoded as ASN.1 PER, using binary content transfer 1862 encoding 1863 o Added text to point out aspects of call handling and metadata/ 1864 control usage, such as use in rejected calls, and solicited MSDs 1865 o Revised use of INFO to require that when a request for an MSD is 1866 sent in INFO, the MSD sent in response is in its own INFO, not the 1867 response to the requesting INFO 1868 o Added material to INFO package registation to comply with 1869 Section 10 of [RFC6086] 1870 o Moved material not required by 3GPP into 1871 [I-D.ietf-ecrit-car-crash], e.g., some of the eCall metadata/ 1872 control elements, attributes, and values 1873 o Revised test call wording to clarify that specific handling is out 1874 of scope 1875 o Revised wording throughout the document to simplify 1876 o Moved new Section 7.1 to be a subsection of 7 1877 o Moved new Section Section 14.9 to be a main section instead of a 1878 subsection of Section 9 1879 o Revised SIP INFO usage and package registration per advice from 1880 Robert Sparks and Paul Kyzivat 1882 17.13. Changes from draft-ietf-06 to draft-ietf-07 1884 o Fixed typo in Acknowledgements 1886 17.14. Changes from draft-ietf-05 to draft-ietf-06 1888 o Added additional security and privacy clarifications regarding 1889 signed and encrypted data 1890 o Additional security and privacy text 1891 o Deleted informative section on ESINets as unnecessary. 1893 17.15. Changes from draft-ietf-04 to draft-ietf-05 1895 o Reworked the security and privacy considerations material in the 1896 document as a whole and in the MIME registation sections of the 1897 MSD and control objects 1898 o Clarified that the element can appear multiple 1899 times within an element 1900 o Fixed IMS definition 1901 o Added clarifying text for the 'msgid' attribute 1903 17.16. Changes from draft-ietf-03 to draft-ietf-04 1905 o Added Privacy Considerations section 1906 o Reworded most uses of non-normative "may", "should", "must", and 1907 "recommended." 1908 o Fixed nits in examples 1910 17.17. Changes from draft-ietf-02 to draft-ietf-03 1912 o Added request to enable cameras 1913 o Improved examples and XML schema 1914 o Clarifications and wording improvements 1916 17.18. Changes from draft-ietf-01 to draft-ietf-02 1918 o Added clarifying text reinforcing that the data exchange is for 1919 small blocks of data infrequently transmitted 1920 o Clarified that dynamic media is conveyed using SIP re-INVITE to 1921 establish a one-way media stream 1922 o Clarified that the scope is the needs of eCall within the SIP 1923 emergency call environment 1924 o Added informative statement that the document may be suitable for 1925 reuse by other ACN systems 1926 o Clarified that normative language for the control block applies to 1927 both IVS and PSAP 1928 o Removed 'ref', 'supported-mime', and elements 1929 o Minor wording improvements and clarifications 1931 17.19. Changes from draft-ietf-00 to draft-ietf-01 1933 o Added further discussion of test calls 1934 o Added further clarification to the document scope 1935 o Mentioned that multi-region vehicles may need to support other 1936 crash notification specifications in addition to eCall 1937 o Added details of the eCall metadata and control functionality 1938 o Added IANA registration for the MIME media type for the control 1939 object 1940 o Added IANA registries for protocol elements and tokens used in the 1941 control object 1942 o Minor wording improvements and clarifications 1944 17.20. Changes from draft-gellens-03 to draft-ietf-00 1946 o Renamed from draft-gellens- to draft-ietf-. 1947 o Added mention of and reference to ETSI TR "Mobile Standards Group 1948 (MSG); eCall for VoIP" 1949 o Added text to Introduction regarding migration/co-existence being 1950 out of scope 1951 o Added mention in Security Considerations that even if the network- 1952 supplied location is just the cell site, this can be useful as a 1953 sanity check on the IVS-supplied location 1954 o Minor wording improvements and clarifications 1956 17.21. Changes from draft-gellens-02 to -03 1958 o Clarifications and editorial improvements. 1960 17.22. Changes from draft-gellens-01 to -02 1962 o Minor wording improvements 1963 o Removed ".automatic" and ".manual" from 1964 "urn:service:test.sos.ecall" registration and discussion text. 1966 17.23. Changes from draft-gellens-00 to -01 1968 o Now using 'EmergencyCallData' for purpose parameter values and 1969 MIME subtypes, in accordance with changes to [RFC7852] 1970 o Added reference to RFC 6443 1971 o Fixed bug that caused Figure captions to not appear 1973 18. References 1974 18.1. Normative References 1976 [msd] CEN, , "Intelligent transport systems -- eSafety -- eCall 1977 minimum set of data (MSD), EN 15722", April 2015. 1979 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1980 Requirement Levels", BCP 14, RFC 2119, 1981 DOI 10.17487/RFC2119, March 1997, 1982 . 1984 [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, 1985 DOI 10.17487/RFC3688, January 2004, 1986 . 1988 [RFC5031] Schulzrinne, H., "A Uniform Resource Name (URN) for 1989 Emergency and Other Well-Known Services", RFC 5031, 1990 DOI 10.17487/RFC5031, January 2008, 1991 . 1993 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 1994 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 1995 DOI 10.17487/RFC5226, May 2008, 1996 . 1998 [RFC6086] Holmberg, C., Burger, E., and H. Kaplan, "Session 1999 Initiation Protocol (SIP) INFO Method and Package 2000 Framework", RFC 6086, DOI 10.17487/RFC6086, January 2011, 2001 . 2003 [RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type 2004 Specifications and Registration Procedures", BCP 13, 2005 RFC 6838, DOI 10.17487/RFC6838, January 2013, 2006 . 2008 [RFC6881] Rosen, B. and J. Polk, "Best Current Practice for 2009 Communications Services in Support of Emergency Calling", 2010 BCP 181, RFC 6881, DOI 10.17487/RFC6881, March 2013, 2011 . 2013 [RFC7303] Thompson, H. and C. Lilley, "XML Media Types", RFC 7303, 2014 DOI 10.17487/RFC7303, July 2014, 2015 . 2017 [RFC7852] Gellens, R., Rosen, B., Tschofenig, H., Marshall, R., and 2018 J. Winterbottom, "Additional Data Related to an Emergency 2019 Call", RFC 7852, DOI 10.17487/RFC7852, July 2016, 2020 . 2022 18.2. Informative references 2024 [CEN] "European Committee for Standardization", 2025 . 2027 [EN_16062] 2028 CEN, , "Intelligent transport systems - eSafety - eCall 2029 High Level Application Requirements (HLAP) Using GSM/UMTS 2030 Circuit Switched Networks, EN 16062", April 2015. 2032 [EN_16072] 2033 CEN, , "Intelligent transport systems - eSafety - Pan- 2034 European eCall operating requirements, EN 16072", April 2035 2015. 2037 [I-D.ietf-ecrit-car-crash] 2038 Gellens, R., Rosen, B., and H. Tschofenig, "Next- 2039 Generation Vehicle-Initiated Emergency Calls", draft-ietf- 2040 ecrit-car-crash-20 (work in progress), December 2016. 2042 [MSG_TR] ETSI, , "ETSI Mobile Standards Group (MSG); eCall for 2043 VoIP", ETSI Technical Report TR 103 140 V1.1.1 (2014-04), 2044 April 2014. 2046 [RFC5012] Schulzrinne, H. and R. Marshall, Ed., "Requirements for 2047 Emergency Context Resolution with Internet Technologies", 2048 RFC 5012, DOI 10.17487/RFC5012, January 2008, 2049 . 2051 [RFC5069] Taylor, T., Ed., Tschofenig, H., Schulzrinne, H., and M. 2052 Shanmugam, "Security Threats and Requirements for 2053 Emergency Call Marking and Mapping", RFC 5069, 2054 DOI 10.17487/RFC5069, January 2008, 2055 . 2057 [RFC6443] Rosen, B., Schulzrinne, H., Polk, J., and A. Newton, 2058 "Framework for Emergency Calling Using Internet 2059 Multimedia", RFC 6443, DOI 10.17487/RFC6443, December 2060 2011, . 2062 [RFC7090] Schulzrinne, H., Tschofenig, H., Holmberg, C., and M. 2063 Patel, "Public Safety Answering Point (PSAP) Callback", 2064 RFC 7090, DOI 10.17487/RFC7090, April 2014, 2065 . 2067 [RFC7378] Tschofenig, H., Schulzrinne, H., and B. Aboba, Ed., 2068 "Trustworthy Location", RFC 7378, DOI 10.17487/RFC7378, 2069 December 2014, . 2071 [SDO-3GPP] 2072 "3d Generation Partnership Project", 2073 . 2075 [SDO-ETSI] 2076 "European Telecommunications Standards Institute (ETSI)", 2077 . 2079 [TS22.101] 2080 3GPP, , "3GPP TS 22.101: Technical Specification Group 2081 Services and System Aspects; Service aspects; Service 2082 principles". 2084 [TS23.167] 2085 3GPP, , "3GPP TS 23.167: IP Multimedia Subsystem (IMS) 2086 emergency sessions". 2088 [TS24.229] 2089 3GPP, , "3GPP TS 24.229: IP multimedia call control 2090 protocol based on Session Initiation Protocol (SIP) and 2091 Session Description Protocol (SDP); Stage 3". 2093 Authors' Addresses 2095 Randall Gellens 2096 Core Technology Consulting 2098 Email: rg+ietf@randy.pensive.org 2100 Hannes Tschofenig 2101 Individual 2103 Email: Hannes.Tschofenig@gmx.net 2104 URI: http://www.tschofenig.priv.at