Network Working Group T. Hardie Internet-Draft Qualcomm, Inc. Intended status: Standards Track A. Newton Expires: March 8, 2007 SunRocket H. Schulzrinne Columbia U. H. Tschofenig Siemens September 4, 2006 LoST: A Location-to-Service Translation Protocol draft-ietf-ecrit-lost-01.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on March 8, 2007. Copyright Notice Copyright (C) The Internet Society (2006). Hardie, et al. Expires March 8, 2007 [Page 1] Internet-Draft LoST September 2006 Abstract This document describes an XML-based protocol for mapping service identifiers and geospatial or civic location information to service contact URIs. In particular, it can be used to determine the location-appropriate PSAP for emergency services. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Requirements Notation . . . . . . . . . . . . . . . . . . . . 6 3. Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4. Resolving Service URNs Using LoST . . . . . . . . . . . . . . 8 5. Query . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5.1. Location Information Element . . . . . . . . . . . . . . . 9 5.2. Service Element . . . . . . . . . . . . . . . . . . . . . 9 5.3. Validate Attribute . . . . . . . . . . . . . . . . . . . . 9 5.4. Query Message Examples . . . . . . . . . . . . . . . . . . 9 6. Response . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 6.1. Uniform Resource Identifiers (URI) Element . . . . . . . . 11 6.2. Display Name Element . . . . . . . . . . . . . . . . . . . 11 6.3. Service Element . . . . . . . . . . . . . . . . . . . . . 11 6.4. ServiceBoundary Element . . . . . . . . . . . . . . . . . 12 6.5. ServiceNumber Element . . . . . . . . . . . . . . . . . . 12 6.6. TimeToLive Attribute . . . . . . . . . . . . . . . . . . . 12 6.7. Validation Element . . . . . . . . . . . . . . . . . . . . 12 6.8. Response Message Examples . . . . . . . . . . . . . . . . 12 7. List Services Query and Response . . . . . . . . . . . . . . . 15 7.1. List Service Query . . . . . . . . . . . . . . . . . . . . 15 7.2. List Service Response . . . . . . . . . . . . . . . . . . 15 8. Status Code Definitions . . . . . . . . . . . . . . . . . . . 17 8.1. Informational 1xx . . . . . . . . . . . . . . . . . . . . 17 8.2. Successful 2xx . . . . . . . . . . . . . . . . . . . . . . 17 8.2.1. 200 OK . . . . . . . . . . . . . . . . . . . . . . . . 17 8.2.2. 201 Service Substitution . . . . . . . . . . . . . . . 17 8.3. Redirection 3xx . . . . . . . . . . . . . . . . . . . . . 17 8.3.1. 301 Move Permanently . . . . . . . . . . . . . . . . . 17 8.3.2. 302 Moved Temporarily . . . . . . . . . . . . . . . . 18 8.3.3. Example . . . . . . . . . . . . . . . . . . . . . . . 18 8.4. Client Error 4xx . . . . . . . . . . . . . . . . . . . . . 18 8.4.1. 400 Bad Request . . . . . . . . . . . . . . . . . . . 18 8.4.2. 403 Forbidden . . . . . . . . . . . . . . . . . . . . 18 8.4.3. 404 Not Found . . . . . . . . . . . . . . . . . . . . 18 8.4.4. 414 Location Error . . . . . . . . . . . . . . . . . . 18 8.4.5. Example . . . . . . . . . . . . . . . . . . . . . . . 18 8.5. Server Error 5xx . . . . . . . . . . . . . . . . . . . . . 20 8.5.1. 500 Server Internal Error . . . . . . . . . . . . . . 20 Hardie, et al. Expires March 8, 2007 [Page 2] Internet-Draft LoST September 2006 8.5.2. 501 Service Not Implemented . . . . . . . . . . . . . 20 8.5.3. 504 Server Time-Out . . . . . . . . . . . . . . . . . 21 8.5.4. Example . . . . . . . . . . . . . . . . . . . . . . . 21 9. LoST Transport . . . . . . . . . . . . . . . . . . . . . . . . 22 10. LoST Uniform Resource Locators . . . . . . . . . . . . . . . . 23 11. Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 12. Deployment Methods . . . . . . . . . . . . . . . . . . . . . . 26 13. Relax NG Schema . . . . . . . . . . . . . . . . . . . . . . . 28 14. Internationalization Considerations . . . . . . . . . . . . . 33 15. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 34 15.1. Content-type registration for 'application/lost+xml' . . . 34 15.2. LoST Relax NG Schema Registration . . . . . . . . . . . . 35 15.3. LoST Namespace Registration . . . . . . . . . . . . . . . 36 15.4. Registration Template . . . . . . . . . . . . . . . . . . 36 16. Security Considerations . . . . . . . . . . . . . . . . . . . 38 17. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 39 18. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 40 19. References . . . . . . . . . . . . . . . . . . . . . . . . . . 41 19.1. Normative References . . . . . . . . . . . . . . . . . . . 41 19.2. Informative References . . . . . . . . . . . . . . . . . . 42 Appendix A. Non-Normative RELAX NG Schema in XML Syntax . . . . . 43 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 51 Intellectual Property and Copyright Statements . . . . . . . . . . 52 Hardie, et al. Expires March 8, 2007 [Page 3] Internet-Draft LoST September 2006 1. Introduction This document describes a protocol for mapping a service identifier [6] and location information compatible with PIDF-LO [11] to one or more service contact URIs. Example contact URI schemes include sip, xmpp, and tel. While the initial focus is on providing mapping functions for emergency services, it is likely that the protocol is applicable to any service URN. For example, in the United States, the "2-1-1" and "3-1-1" services follow a similar location-to-service behavior as emergency services. This document names this protocol usage "LoST" for Location-to- Service Translation Protocol. The features of LoST are: o Supports queries using civic as well as geospatial location information. o Support for recursive and iterative resolution. o Support for address validation. o A hierarchical deployment of mapping servers is independent of civic location labels. o Indication of errors in the location data to facilitate debugging and proper user feedback while simultaneously providing best- effort answers. o Mapping can be based on either civic or geospatial location information, with uniform protocol treatment of both. o Support for overlapping service regions. o Satisfies the requirements [5] for mapping protocols. o Minimizes round trips by caching individual mappings and by supporting return of coverage regions ("hinting"). o Facilitates reuse of Transport Layer Security (TLS). This document focuses on the description of the protocol between the mapping client (seeker or resolver) and the mapping server (resolver or other servers). The relationship between other functions, such as discovery of mapping servers, data replication and the overall mapping server architecture in general, will be described in a separate document. [20] is a first attempt to describe such a mapping server architecture. Hardie, et al. Expires March 8, 2007 [Page 4] Internet-Draft LoST September 2006 The high-level protocol operation can be described as follows: Location Info +----------+ --------> | | Service | LoST | URN | Server | --------> | | +----------+ Query URI +----------+ <------- | | Optional | LoST | Info (hints)| Server | <------- | | +----------+ Response Figure 1: Overview The query message carries location information and a service identifier encoded as a Uniform Resource Name (URN) (see [6]) from the LoST client to the LoST server. The LoST server uses its database to map the input values to a Uniform Resource Identifiers (URI) and returns it including optional information such as hints about the service boundary in a response message back to the LoST client. Hardie, et al. Expires March 8, 2007 [Page 5] Internet-Draft LoST September 2006 2. Requirements Notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [3]. Hardie, et al. Expires March 8, 2007 [Page 6] Internet-Draft LoST September 2006 3. Usage The client queries a server, indicating the desired service and location information. If the query succeeds, the server returns a result that includes one or more URIs for reaching the appropriate service for the location indicated. Depending on the query, the result may contain a service boundary where the same mapping would apply, a reference to another server to which the client should send a query, or an error messages indicating problems. The combination of these components are left to the needs and policy of the jurisdiction where the server is being operated. The client may perform the mapping at any time. Among the common triggers for mapping are: 1. When the client starts up and/or attaches to a new network location. 2. When the client detects that its location has changed sufficiently that it is outside the bounds of the region returned in an earlier query. 3. When cached mapping information has expired. 4. When calling for a particular service. During such calls, a client may want to request a short response that contains only the mapping data, omitting service boundary information. Cached answers are expected to be used by clients only after failing to accomplish a location-to-URI mapping at call time. Cache entries may expire according to their time-to-live value, or they may become invalid if the location of the caller's device moves outside the boundary limits of the cache entry. Boundaries for cache entries may be set in both geospatial and civic terms. Hardie, et al. Expires March 8, 2007 [Page 7] Internet-Draft LoST September 2006 4. Resolving Service URNs Using LoST If a LoST URL contains a host name rather than an IP address, clients need to perform an U-NAPTR [17] lookup to obtain a DNS A record and IP address. These records map the 'host' part of the LoST URL to one or more URLs indicating the protocol to carry the LoST request. In this document, only the HTTP and HTTPS URL schemes are defined. Note that the HTTP URL can be any valid HTTP URL, including those containing path elements. Here is an example: example.com. IN NAPTR 100 10 "u" "LoST:https" "!*.!https://lostserver.example.com/secure!" "" IN NAPTR 200 10 "u" "LoST:http" "!*.!http://lostserver.example.com!" "" Hardie, et al. Expires March 8, 2007 [Page 8] Internet-Draft LoST September 2006 5. Query LoST provides the ability to use civic or geospatial location information in the query message. In addition to location information the query also contains a service identifier. An optional parameter might furthermore request the LoST server to validate location information. 5.1. Location Information Element LoST supports a query using geospatial and civic location information using the query. Geospatial location information uses GML format [10] and civic location information utilizes the format defined in [16]. This document does not define location formats. 5.2. Service Element The type of service desired is specified by the element. The (emergency) service identifiers listed in the registry established with [6] will be used in this document. The element is a mandatory element. In case the database at the LoST server does not provided service for the specific geographical region the LoST server has various choices with regard to the response: o It can send an error response. o It can map one service to another one, if appropriate, and return a different service identifier as described in Section 6.3. o It can populate the URIs of one service to another service. The operation of the LoST server is largely a policy issue. No behavior is mandated in this document. Guidelines for operating a LoST server for emergency services is provided in [21]. 5.3. Validate Attribute The 'validate' attribute implements the validation behavior described in [5]. 5.4. Query Message Examples This section shows an example of a query message providing geospatial and civic location information. Hardie, et al. Expires March 8, 2007 [Page 9] Internet-Draft LoST September 2006 37:46:30N 122:25:10W urn:service:sos.police Figure 3: Query Message Example using Geospatial Location Information The example above shows a query using geospatial location information with no validation required and asking for the 'urn:service:sos.police' service. Germany Bavaria Munich Neu Perlach 96 81675 urn:service:sos.police Figure 4: Query Message Example using Civic Location Information The example above shows a query using a civic location in Munich asking for the 'urn:service:sos.police' service. The query indicates that validation is not desired and the query has to be executed recursively. Hardie, et al. Expires March 8, 2007 [Page 10] Internet-Draft LoST September 2006 6. Response A response message might either contain civic or geospatial location information depending on the type of the query. If the findServiceByLocation query message contained civic location information then the element of the response message will also contain civic information. If the findServiceByLocation query message contained geospatial location information then the element of the response message will contain a GML polygon. More information about the element can be found at Section 6.4. 6.1. Uniform Resource Identifiers (URI) Element Each element contains an appropriate contact URI for the service for which mapping was requested. elements are of type xs:anyURI. In the emergency service context operators are strongly discouraged from using relative URIs, even though these are permitted by the type. 6.2. Display Name Element Each element contains a string that is suitable for display. elements are of type "text" that is suitable for internationalized human-readable text. 6.3. Service Element The element is an optional element in the response message. The (emergency) service identifiers listed in the registry established with [6] will be used in this document. If the service that was requested by the LoST client is not available for a particular location then the server MAY return an alternate service. If it does so, it MUST indicate the actual service returned (i.e., its service URN). Alternatively, the LoST server MAY return an error response indicating that the requested service is not available. The following example illustrates the main idea. If there is a region that only understands the 'urn:service:sos' service and not 'urn:service:sos.fire', 'urn:service:sos.ambulance', and 'urn:service:sos.police'. If a LoST client asks for the 'urn:service:sos.fire' service then the LoST server could, depending on the local policy at the LoST server, return: 1. 'urn:service:sos', or 2. 'urn:service:sos.fire' with the values of 'urn:service:sos' being populated to 'urn:service:sos.fire', or Hardie, et al. Expires March 8, 2007 [Page 11] Internet-Draft LoST September 2006 3. an error message In case of (1) the element carries the value of 'urn:service:sos'. 6.4. ServiceBoundary Element Each element contains either one or more civic location elements derived from the GeoPriv civic address schema or a GML-based polygon. The element indicates where the same query would yield to the same response, i.e., it provides information about the service boundary. 6.5. ServiceNumber Element TBD: This element contains the (emergency) service number, which is a string of digits used to reach the (emergency) service. 6.6. TimeToLive Attribute Each timeToLive attribute is a positive integer, expressing the validity period of the response in seconds. The LoST client MUST NOT consider the returned location current after the expiration of the validity period. 6.7. Validation Element The element contains a string that is composed of concatenated tokens separated by a whitespace. These tokens refer to the civic location labels used in child elements of the element from the request that have been recognized as valid by the server. The following code snippet indicates that the civic address labels 'country', 'A1', 'A3', 'A6, 'PC' have been valided by the LoST server. country A1 A3 A6 PC 6.8. Response Message Examples This section shows an example of a query message providing geospatial and civic location information. Hardie, et al. Expires March 8, 2007 [Page 12] Internet-Draft LoST September 2006 New York City Police Department urn:service:sos.police 37.775 -122.4194 37.555 -122.4194 37.555 -122.4264 37.775 -122.4264 37.775 -122.4194 sip:nypd@example.com xmpp:nypd@example.com 911 Figure 6: Response Message Example using Geospatial Location Service Boundary Hints This example shows a response with two URIs for the previously queried service URN. Information about the service boundary is provided by a GML polygon. The element indicates the valid service number for the expressed location and service URN. Hardie, et al. Expires March 8, 2007 [Page 13] Internet-Draft LoST September 2006 Munich Police Department urn:service:sos.police Germany Bavaria Munich 81675 sip:munich-police@example.com xmpp:munich-police@example.com 110 Figure 7: Response Message Example providing Civic Location Service Boundary Hints This example shows a response that returns two URIs (one for SIP and another one for XMPP), a distring that indicates the valid distring for the location provided in the query, a hint about the service boundary in the element and information about the validated civic address fields. The timeToLive attribute indicates that the returned information can be cached for 10000 seconds and provides a * element with additional, textual information about the returned information. Hardie, et al. Expires March 8, 2007 [Page 14] Internet-Draft LoST September 2006 7. List Services Query and Response 7.1. List Service Query This subsection describes a mechanism that offers the LoST client to query for available service identifiers supported by the LoST server. The listServices query MUST carry the and the element. The LoST server MUST return only immediate child elements of the service identifier specified in the element of the listServices query available for the provided location information. 37:46:30N 122:25:10W urn:service:sos Figure 8: Example for a List Service Query This listService query aims to query the immediate child elements of the 'urn:service:sos' URN. 7.2. List Service Response This subsection describes the response message that provides the LoST client with the list of immediate child service identifiers based on the service identifier provided by LoST client with respect to the location information provided in the listService query. The following example shows the response to the listServices query example of Figure 8 listing the available services offered by the LoST server starting with 'urn:service:sos.ambulance' and finishing with 'urn:service:sos.suicide'. Hardie, et al. Expires March 8, 2007 [Page 15] Internet-Draft LoST September 2006 urn:service:sos.ambulance urn:service:sos.animal-control urn:service:sos.fire urn:service:sos.gas urn:service:sos.mountain urn:service:sos.marine urn:service:sos.physician urn:service:sos.poison urn:service:sos.police urn:service:sos.suicide Figure 9: Example for the Response to a List Service Query Hardie, et al. Expires March 8, 2007 [Page 16] Internet-Draft LoST September 2006 8. Status Code Definitions Each response contains a element that conveys a numeric status code and a reason phrase indicating the success or failure of the response. The appearance of other elements in the response depends on the status code. Hence, different elements are used for groups of status codes. Status codes always have three digits; the list of status codes is meant to be extensible by IANA registration and follows the general pattern of the Session Initiation Protocol (SIP) [22] and HTTP [14]. The first digit indicates the type of response, with '2' signaling a successful request, '3' a redirection, '4' a request failure due to client behavior, and '5' a server failure. If used within HTTP, LoST also utilizes the normal HTTP status codes. However, the HTTP request can succeed, while the LoST request caused an error. All LoST status codes appear in HTTP 200 (OK) responses. For example, a LoST 404, 414 or 500 status would occur in an HTTP 200 response. Temporary unavailability of the service should be indicated by an HTTP 505 (Service Unavailable) status code. [Editor's Note: Does this make any sense or should all or some LoST errors occur in a non-200 HTTP response?] 8.1. Informational 1xx This document does not define informational status codes. 8.2. Successful 2xx 8.2.1. 200 OK The query completed successfully. 8.2.2. 201 Service Substitution The service requested is not available for the location requested, but the server is configured to provide a replacement service. 8.3. Redirection 3xx 8.3.1. 301 Move Permanently The requested location is being mapped by a different server and all future requests for that location (and locations in the service area) Hardie, et al. Expires March 8, 2007 [Page 17] Internet-Draft LoST September 2006 should be directed to that server. 8.3.2. 302 Moved Temporarily The requested location is being mapped by a different server, but future requests should continue to use this server. 8.3.3. Example This is an example of an error message with a 302 status code: 8.4. Client Error 4xx 8.4.1. 400 Bad Request The request could not be understood due to malformed syntax. 8.4.2. 403 Forbidden The server understood the request, but is refusing to fulfill it. Authorization will not help, and the request SHOULD NOT be repeated. 8.4.3. 404 Not Found The server has definitive information that there is no service mapping for the location specified. 8.4.4. 414 Location Error The location provided does not exist or fields within the location information are contradictory. 8.4.5. Example The first example shows an error message with a 414 status code that is attached to the response message indicating that there was a problem with the postal code: Hardie, et al. Expires March 8, 2007 [Page 18] Internet-Draft LoST September 2006 New York City Police Department unknown US New York New York sip:nypd@example.com xmpp:nypd@example.com 911 The second example shows an error message with a 414 status code that is attached to the response message indicating that there was a problem with the provided geospatial location information: Hardie, et al. Expires March 8, 2007 [Page 19] Internet-Draft LoST September 2006 New York City Police Department urn:service:sos.police 37.775 -122.4194 37.555 -122.4194 37.555 -122.4264 37.775 -122.4264 37.775 -122.4194 sip:nypd@example.com xmpp:nypd@example.com 911 8.5. Server Error 5xx 8.5.1. 500 Server Internal Error The server encountered an unexpected condition that prevented it from fulfilling the request. The client MAY retry the request after several seconds. 8.5.2. 501 Service Not Implemented The server does not implement mapping for the service requested and cannot provide an alternate service. Hardie, et al. Expires March 8, 2007 [Page 20] Internet-Draft LoST September 2006 8.5.3. 504 Server Time-Out A server time-out occurs if the server contacted tries to recursively resolve the query, but cannot get an answer within the time limit set for the query. 8.5.4. Example This is an example of an error message with a 500 status code: Server failure Hardie, et al. Expires March 8, 2007 [Page 21] Internet-Draft LoST September 2006 9. LoST Transport LoST needs an underlying protocol transport mechanisms to carry requests and responses. This document defines the use of LoST over HTTP and HTTP-over-TLS; other mechanisms are left to future documents. The available transport mechanisms are indicated in the LoST U-NAPTR DNS resource record. In protocols that support content type indication, LoST uses the media type application/lost+xml. When using HTTP [14] and HTTP-over-TLS [15], LoST requests use the HTTP POST method. All HTTP responses are applicable. The HTTP URL is derived from the LoST URL via U-NAPTR translation, as discussed in Section 4. Hardie, et al. Expires March 8, 2007 [Page 22] Internet-Draft LoST September 2006 10. LoST Uniform Resource Locators LoST Uniform Resource Locators (URLs) follow the format of URLs defined in RFC 3986 [9], with the following ABNF: LoST-URI = "lost:" host 'host' is defined in Section 3.2.2 of RFC 3986 [9]. An example is 'lost:lostserver.example.com' Hardie, et al. Expires March 8, 2007 [Page 23] Internet-Draft LoST September 2006 11. Example After performing link layer attachment and end host performs stateful address autoconfiguration (in our example) using DHCP. Then, DHCP provides the end host with civic location as described in [19]. +--------+---------------+ | CAtype | CAvalue | +--------+---------------+ | 0 | US | | 1 | New York | | 3 | New York | | 6 | Broadway | | 22 | Suite 75 | | 24 | 10027-0401 | +--------+---------------+ Figure 14: DHCP Civic Information Example Additionally, DHCP may provide information about the LoST server that can be contacted. Alternatively, an additional step of indirection is possible, for example by having DHCP return a domain name that has to be resolved to one or more IP addresses hosting LoST servers. Both at attachment time and call time, the client places a LoST request, including its civic location and the desired service. The request is shown below: US New York New York Broadway Suite 75 10027-0401 urn:service:sos.police Mapping Request Hardie, et al. Expires March 8, 2007 [Page 24] Internet-Draft LoST September 2006 Since the contacted LoST server has the requested information available the following response is returned. The element indicates, as a human readable display string, that the 'New York City Police Department' is responsible for the given geographical area. The indicated URI allows the user to start communication using SIP or XMPP. The element indicates which parts of the civic address were matched successfully against a database and represent a known address. Other parts of the address, here, the suite number, were ignored and not validated. The element indicates that all of New York City would result in the same response. The element indicates that the service can be reached via the emergency service number 911. New York City Police Department unknown US New York New York sip:nypd@example.com xmpp:nypd@example.com 911 Mapping Response Hardie, et al. Expires March 8, 2007 [Page 25] Internet-Draft LoST September 2006 12. Deployment Methods Because services for emergency contact resolution may differ depending on local or service needs, this document only specifies the "wire format" for LoST services and explicitly leaves open the possibility for many different types of deployment. For instance: During discovery, a client may be directed to issue all queries to an LoST service completely authoritative for a given jurisdiction. A client may be directed to issue queries to an LoST server that acts as a reflector. In such a case, the LoST server analyzes the query to determine the best server to which to refer the client. Or the client may be directed to a server that performs further resolution on behalf of the client. A LoST service may also be represented by multiple LoST servers, either grouped together or at multiple network locations. Using S-NAPTR [24], clients may be given a list of multiple servers to which queries can be sent for a single service. For instance, the service at emergency.example.com may advertise LoST service at local1.emergency.example.com, local2.emergency.example.com, and master.emergency.example.com. Each server may given a different preference. In this case, 'local-1' and 'local-2' may be given a lower preference (more preferred) than 'master', which might be a busier server or located further away. +-----------+ pref 10 +-----------+ | |-------------------->+ | | client |------ | local-1 | | |--- \ | | +-----------+ \ \ +-----------+ \ \ \ \ +-----------+ \ \ pref 10 | | \ --------->| local-2 | \ | | \ +-----------+ \ \ +-----------+ \ pref 20 | | ------------------------->| master | Hardie, et al. Expires March 8, 2007 [Page 26] Internet-Draft LoST September 2006 | | +-----------+ Hardie, et al. Expires March 8, 2007 [Page 27] Internet-Draft LoST September 2006 13. Relax NG Schema This section provides the Relax NG schema used by LoST protocol in the compact form. The verbose form is included in Appendix A. default namespace = "urn:ietf:params:xml:ns:lost1" namespace a = "http://relaxng.org/ns/compatibility/annotations/1.0" namespace ns1 = "urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" namespace ns2 = "http://www.opengis.net/gml" ## ## Location-to-Service Translation Protocol (LoST) ## ## A LoST XML instance has three "root" types: ## the findServiceByLocation query, the listServices query, ## and the response to these queries. ## start = findServiceByLocation | listServices | response ## ## The queries. ## div { findServiceByLocation = element findServiceByLocation { query, attribute validate { xsd:boolean >> a:defaultValue [ "false" ] }? } listServices = element listServices { query } } ## ## The response. ## div { response = element response { ## ## 2xx responses. ## (result | element serviceList { list { xsd:anyURI* }, status })?, Hardie, et al. Expires March 8, 2007 [Page 28] Internet-Draft LoST September 2006 ## ## 3xx, 4xx, and 4xx responses. ## ((error | redirect | failure)?), extensionPoint } } ## ## Query pattern. ## div { query = element locationInfo { anyElement* }, element service { xsd:anyURI }, extensionPoint, [ a:defaultValue [ "recursive" ] ] attribute operation { text }? } ## ## A result. ## div { ## ## 2xx response. ## result = element result { element displayName { xsd:string, attribute xml:lang { xsd:language } }?, element service { xsd:anyURI }, element serviceBoundary { (civicLocation, polygon?) | (civicLocation?, polygon) }?, element uri { xsd:anyURI }+, element serviceNumber { xsd:string { pattern = "[0-9]+" } }?, element validation { list { xsd:QName* } }?, extensionPoint, attribute timeToLive { xsd:positiveInteger }, status } Hardie, et al. Expires March 8, 2007 [Page 29] Internet-Draft LoST September 2006 } ## ## Non-result responses. ## div { ## ## 5xx response. ## error = element error { status, extensionPoint } ## ## 3xx response. ## redirect = element redirect { status, attribute redirect { xsd:anyURI }, extensionPoint } ## ## 4xx response. ## failure = element failure { status, element cause { attribute name { xsd:QName }, attribute message { xsd:string }, attribute xml:lang { xsd:language } }*, extensionPoint } } ## ## Status pattern. ## div { status = attribute status { xsd:positiveInteger }, attribute extendedStatus { xsd:positiveInteger }?, (attribute message { xsd:string }, attribute xml:lang { xsd:language })? } Hardie, et al. Expires March 8, 2007 [Page 30] Internet-Draft LoST September 2006 ## ## Patterns for inclusion of elements from schemas in ## other namespaces. ## div { ## ## A wildcard pattern for including any element ## from any other namespace. ## anyElement = element * { (attribute * { text } | text | anyElement)* } ## ## A point where future extensions ## (elements from other namesapces) ## can be added. ## extensionPoint = anyElement* ## ## A pattern to include the GEOPRIV civil location elements. ## civicAddress = element ns1:* { (attribute * { text } | text | anyElement)* } ## ## A definition of civic location from GEOPRIV. ## civicLocation = element civicLocation { civicAddress*, anyElement* } ## ## A pattern to include GML elements. ## GML = element ns2:* { (attribute * { text } | text | anyElement)* } Hardie, et al. Expires March 8, 2007 [Page 31] Internet-Draft LoST September 2006 polygon = element ns2:Polygon { attribute * { text }*, GML } } Hardie, et al. Expires March 8, 2007 [Page 32] Internet-Draft LoST September 2006 14. Internationalization Considerations This mechanism is largely for passing protocol information from one subsystem to another; as such, most of its elements are tokens not meant for direct human consumption. If these tokens are presented to the end user, some localization may need to occur. The content of the element may be displayed to the end user, and it is thus a complex type designed for this purpose. Hardie, et al. Expires March 8, 2007 [Page 33] Internet-Draft LoST September 2006 15. IANA Considerations 15.1. Content-type registration for 'application/lost+xml' This specification requests the registration of a new MIME type according to the procedures of RFC 4288 [13] and guidelines in RFC 3023 [12]. MIME media type name: application MIME subtype name: lost+xml Mandatory parameters: none Optional parameters: charset Indicates the character encoding of enclosed XML. Encoding considerations: Uses XML, which can employ 8-bit characters, depending on the character encoding used. See RFC 3023 [12], Section 3.2. Security considerations: This content type is designed to carry LoST protocol payloads. Interoperability considerations: None Published specification: RFCXXXX [NOTE TO IANA/RFC-EDITOR: Please replace XXXX with the RFC number of this specification.] this document Applications which use this media type: Emergency and Location-based Systems Hardie, et al. Expires March 8, 2007 [Page 34] Internet-Draft LoST September 2006 Additional information: Magic Number: None File Extension: .lostxml Macintosh file type code: 'TEXT' Personal and email address for further information: Hannes Tschofenig, Hannes.Tschofenig@siemens.com Intended usage: LIMITED USE Author: This specification is a work item of the IETF ECRIT working group, with mailing list address . Change controller: The IESG 15.2. LoST Relax NG Schema Registration URI: urn:ietf:params:xml:ns:lost Registrant Contact: IETF ECRIT Working Group, Hannes Tschofenig (Hannes.Tschofenig@siemens.com). Relax NG Schema: The Relax NG schema to be registered is contained in Section 13. Its first line is default namespace = "urn:ietf:params:xml:ns:lost1" and its last line is } Hardie, et al. Expires March 8, 2007 [Page 35] Internet-Draft LoST September 2006 15.3. LoST Namespace Registration URI: urn:ietf:params:xml:ns:lost Registrant Contact: IETF ECRIT Working Group, Hannes Tschofenig (Hannes.Tschofenig@siemens.com). XML: BEGIN LoST Namespace

Namespace for LoST

urn:ietf:params:xml:ns:lost

See RFCXXXX [NOTE TO IANA/RFC-EDITOR: Please replace XXXX with the RFC number of this specification.].

END 15.4. Registration Template This registration template is in accordance with [8]. URL scheme name: lost URL scheme syntax: See Section 10 Character encoding considerations: See Section 10 Hardie, et al. Expires March 8, 2007 [Page 36] Internet-Draft LoST September 2006 Intended Use: The intended usage is described in this document. Application and protocols which use this scheme: The usage of the LoST URL scheme is targeted for this document and hence for location-based services that make use of the mapping protocol specified in this document. Interoperability considerations: None Security considerations: See Section 16 Relevant publications: This document provides the relevant context for this URL scheme. Contact: Hannes Tschofenig, Hannes.Tschofenig@siemens.com Author/Change controller: The IESG Hardie, et al. Expires March 8, 2007 [Page 37] Internet-Draft LoST September 2006 16. Security Considerations There are multiple threats to the overall system of which service mapping forms a part. An attacker that can obtain service contact URIs can use those URIs to attempt to disrupt those services. An attacker that can prevent the lookup of contact URIs can impair the reachability of such services. An attacker that can eavesdrop on the communication requesting this lookup can surmise the existence of an emergency and possibly its nature, and may be able to use this to launch a physical attack on the caller. To avoid that an attacker can modify the query or its result, the authors RECOMMEND the use of channel security, such as TLS, with LoST. A more detailed description of threats and security requirements are provided in [4]. Hardie, et al. Expires March 8, 2007 [Page 38] Internet-Draft LoST September 2006 17. Acknowledgments [Editor's Note: Names need to be added here. Forgot it...Sorry.] Hardie, et al. Expires March 8, 2007 [Page 39] Internet-Draft LoST September 2006 18. Open Issues Please find open issues at: http://www.ietf-ecrit.org:8080/lost/ Hardie, et al. Expires March 8, 2007 [Page 40] Internet-Draft LoST September 2006 19. References 19.1. Normative References [1] World Wide Web Consortium, "XML Schema Part 2: Datatypes", W3C XML Schema, October 2000, . [2] World Wide Web Consortium, "XML Schema Part 1: Structures", W3C XML Schema, October 2000, . [3] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [4] Taylor, T., "Security Threats and Requirements for Emergency Call Marking and Mapping", draft-ietf-ecrit-security-threats-03 (work in progress), July 2006. [5] Schulzrinne, H. and R. Marshall, "Requirements for Emergency Context Resolution with Internet Technologies", draft-ietf-ecrit-requirements-12 (work in progress), August 2006. [6] Schulzrinne, H., "A Uniform Resource Name (URN) for Services", draft-ietf-ecrit-service-urn-05 (work in progress), August 2006. [7] Mealling, M., "The IETF XML Registry", draft-mealling-iana-xmlns-registry-05 (work in progress), June 2003. [8] Petke, R. and I. King, "Registration Procedures for URL Scheme Names", BCP 35, RFC 2717, November 1999. [9] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, January 2005. [10] OpenGIS, "Open Geography Markup Language (GML) Implementation Specification", OGC OGC 02-023r4, January 2003. [11] Peterson, J., "A Presence-based GEOPRIV Location Object Format", RFC 4119, December 2005. [12] Murata, M., St. Laurent, S., and D. Kohn, "XML Media Types", RFC 3023, January 2001. Hardie, et al. Expires March 8, 2007 [Page 41] Internet-Draft LoST September 2006 [13] Freed, N. and J. Klensin, "Media Type Specifications and Registration Procedures", BCP 13, RFC 4288, December 2005. [14] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. [15] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000. [16] Thomson, M. and J. Winterbottom, "Revised Civic Location Format for PIDF-LO", draft-ietf-geopriv-revised-civic-lo-02 (work in progress), April 2006. [17] Daigle, L., "Domain-based Application Service Location Using URIs and the Dynamic Delegation Discovery Service (DDDS)", draft-daigle-unaptr-00 (work in progress), June 2006. 19.2. Informative References [18] Schulzrinne, H., "The tel URI for Telephone Numbers", RFC 3966, December 2004. [19] Schulzrinne, H., "Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Option for Civic Addresses Configuration Information", draft-ietf-geopriv-dhcp-civil-09 (work in progress), January 2006. [20] Schulzrinne, H., "Location-to-URL Mapping Architecture and Framework", draft-ietf-ecrit-mapping-arch-00 (work in progress), August 2006. [21] Rosen, B. and J. Polk, "Best Current Practice for Communications Services in support of Emergency Calling", draft-rosen-sos-phonebcp-01 (work in progress), June 2006. [22] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, June 2002. [23] Rosenberg, J., "Interactive Connectivity Establishment (ICE): A Methodology for Network Address Translator (NAT) Traversal for Offer/Answer Protocols", draft-ietf-mmusic-ice-10 (work in progress), August 2006. [24] Daigle, L. and A. Newton, "Domain-Based Application Service Location Using SRV RRs and the Dynamic Delegation Discovery Service (DDDS)", RFC 3958, January 2005. Hardie, et al. Expires March 8, 2007 [Page 42] Internet-Draft LoST September 2006 Appendix A. Non-Normative RELAX NG Schema in XML Syntax Location-to-Service Translation Protocol (LoST) A LoST XML instance has three "root" types: the findServiceByLocation query, the listServices query, and the response to these queries.
The queries. false
Hardie, et al. Expires March 8, 2007 [Page 43] Internet-Draft LoST September 2006
The response. 2xx responses. 3xx, 4xx, and 4xx responses.
Query pattern. Hardie, et al. Expires March 8, 2007 [Page 44] Internet-Draft LoST September 2006 recursive
A result. 2xx response. Hardie, et al. Expires March 8, 2007 [Page 45] Internet-Draft LoST September 2006 [0-9]+
Non-result responses. 5xx response. Hardie, et al. Expires March 8, 2007 [Page 46] Internet-Draft LoST September 2006 3xx response. 4xx response.
Status pattern. Hardie, et al. Expires March 8, 2007 [Page 47] Internet-Draft LoST September 2006
Patterns for inclusion of elements from schemas in other namespaces. A wildcard pattern for including any element from any other namespace. Hardie, et al. Expires March 8, 2007 [Page 48] Internet-Draft LoST September 2006 A point where future extensions (elements from other namespaces) can be added. A pattern to include the GEOPRIV civil location elements. A definition of civic location from GEOPRIV. A pattern to include GML elements. Hardie, et al. Expires March 8, 2007 [Page 49] Internet-Draft LoST September 2006
Hardie, et al. Expires March 8, 2007 [Page 50] Internet-Draft LoST September 2006 Authors' Addresses Ted Hardie Qualcomm, Inc. Email: hardie@qualcomm.com Andrew Newton SunRocket 8045 Leesburg Pike, Suite 300 Vienna, VA 22182 US Phone: +1 703 636 0852 Email: andy@hxr.us Henning Schulzrinne Columbia University Department of Computer Science 450 Computer Science Building New York, NY 10027 US Phone: +1 212 939 7004 Email: hgs+ecrit@cs.columbia.edu URI: http://www.cs.columbia.edu Hannes Tschofenig Siemens Otto-Hahn-Ring 6 Munich, Bavaria 81739 Germany Phone: +49 89 636 40390 Email: Hannes.Tschofenig@siemens.com URI: http://www.tschofenig.com Hardie, et al. Expires March 8, 2007 [Page 51] Internet-Draft LoST September 2006 Full Copyright Statement Copyright (C) The Internet Society (2006). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Hardie, et al. Expires March 8, 2007 [Page 52]