One document matched: draft-ietf-ecrit-lost-sync-07.xml


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<rfc ipr="trust200902" category="exp" docName="draft-ietf-ecrit-lost-sync-07.txt">
    <front>
        <title abbrev="LoST Sync">Synchronizing Location-to-Service Translation (LoST) Protocol
            based Service Boundaries and Mapping Elements</title>

        <author initials="H." surname="Schulzrinne" fullname="Henning Schulzrinne">
            <organization>Columbia University</organization>
            <address>
                <postal>
                    <street>Department of Computer Science</street>
                    <street>450 Computer Science Building</street>
                    <city>New York</city>
                    <region>NY</region>
                    <code>10027</code>
                    <country>US</country>
                </postal>
                <phone>+1 212 939 7004</phone>
                <email>hgs+ecrit@cs.columbia.edu</email>
                <uri>http://www.cs.columbia.edu</uri>
            </address>
        </author>

        <author fullname="Hannes Tschofenig" initials="H." surname="Tschofenig">
            <organization>Nokia Siemens Networks</organization>
            <address>
                <postal>
                    <street>Linnoitustie 6</street>
                    <city>Espoo</city>
                    <code>02600</code>
                    <country>Finland</country>
                </postal>
                <phone>+358 (50) 4871445</phone>
                <email>Hannes.Tschofenig@gmx.net</email>
                <uri>http://www.tschofenig.priv.at</uri>
            </address>
        </author>

        <date year="2009"/>
        <area>RAI</area>
        <workgroup>ECRIT</workgroup>
        <keyword>Internet-Draft</keyword>
        <keyword>Location</keyword>
        <abstract>
            <t>The Location-to-Service Translation (LoST) protocol is an XML-based protocol for
                mapping service identifiers and geodetic or civic location information to service
                URIs and service boundaries. In particular, it can be used to determine the
                location-appropriate Public Safety Answering Point (PSAP) for emergency services. </t>
            <t>The main data structure, the <mapping> element, used for encapsulating
                information about service boundaries is defined in the LoST protocol specification
                and circumscribes the region within which all locations map to the same service
                Uniform Resource Identifier (URI) or set of URIs for a given service.</t>
            <t>This document defines an XML protocol to exchange these mappings between two nodes.
                This mechanism is designed for the exchange of authoritative <mapping>
                elements between two entities. Exchanging cached <mapping> elements,
                i.e. non-authoritative elements, is possible but not envisioned. In any case, this
                document can also be used without the LoST protocol even though the format of the
                <mapping> element is re-used from the LoST specification.</t>
        </abstract>

    </front>
    <middle>

        <section title="Introduction">

            <t>The <xref target="RFC5222">LoST (Location-to-Service Translation) protocol</xref>
                maps service identifiers and geodetic or civic location information to service URIs.
                The main data structure, the <mapping> element, used for encapsulating
                information about service boundaries is defined in the LoST protocol specification
                and circumscribes the region within which all locations map to the same service
                Uniform Resource Identifier (URI) or set of URIs for a given service.</t>

            <t>This mechanism is designed for the exchange of authoritative <mapping>
                elements between two entities (the LoST Sync source and the LoST Sync destination).</t>
            <t> The LoST Sync mechanism can, for example, be used in the LoST architecture, as
                specified in the <xref target="I-D.ietf-ecrit-mapping-arch"/>. There, LoST servers
                act in different roles that cooperate to provide an ubiquitous, globally scalable
                and resilient mapping service. In the LoST mapping architecture, LoST servers can
                peer, i.e., have an on-going data exchange relationship. Peering relationships are
                set up manually, based on local policies. A server can peer with any number of other
                servers. Forest guides peer with other forest guides; resolvers peer with forest
                guides and other resolvers (in the same cluster); authoritative mapping servers peer
                with forest guides and other authoritative servers, either in the same cluster or
                above or below them in the tree. Authoritative mapping servers push coverage regions
                "up" the tree, i.e., from child nodes to parent nodes. The child informs the parent
                of the geospatial or civic region that it covers for a specific service.</t>

            <t>As an example consider the following two forest guides for two countries, country Foo
                and country Bar. Country Foo has only 5 PSAPs and the boundaries for fire, police
                and ambulance are identical. Country Bar has a large number of PSAPs but their
                emergency services architecture is designed in a way that all emergency calls are
                served by a small number of replicated and highly available Emergency Services
                Routing Proxies (ESRPs). These ESRPs give outside countries the illusion of a single
                PSAP. From a call routing point of view a ESRP receiving an emergency call performs
                location based routing to forward calls to one of the large number of PSAPs. </t>

            <t>Country Foo and country Bar utilize LoST Sync to keep their mappings up-to-date.
                Every country is responsible for maintaining their own mapping information and hence
                they configure their LoST Sync nodes in a way that they exchange the respective
                mapping information. In this case, the mapping data will be synchronized in both
                directions. Since the amount of data being exchanged is small and the expected rate
                of change is low the LoST Sync nodes are configured to always exchange all their
                mapping information whenever a change happens. </t>

            <t>This document defines two types of exchanges and those are best described by the
                exchange between two nodes as shown in <xref target="overview1"/> and <xref
                    target="overview2"/>. The protocol exchange always runs between a LoST Sync
                source and a LoST Sync destination. Node A in the examples of <xref
                    target="overview1"/> and <xref target="overview2"/> has mappings that Node B is
                going to retrieve. Node A acts as the source for the data and Node B is the
                destination.</t>

            <t> The <getMappingsRequest> request allows a LoST Sync source to request
                mappings from a LoST Sync destination.<figure anchor="overview1"
                    title="Querying for Mappings with a <getMappingsRequest> Message">
                    <artwork><![CDATA[
   +---------+                   +---------+
   | Node B  |                   | Node A  |
   | acting  |                   | acting  |
   | as      |                   | as      |
   | LoST    |                   | LoST    |
   | Sync    |                   | Sync    |
   | Dest.   |                   | Source  |
   +---------+                   +---------+
       |                              |
       |                              |
       |                              |
       | <getMappingsRequest>         |
       |----------------------------->|
       |                              |
       | <getMappingsResponse>        |
       |<-----------------------------|
       |                              |
       |                              |
       |                              |
]]></artwork>
                </figure>
            </t>

            <t>Note that in the exchange illustrated in <xref target="overview1"/> Node B issuing
                the first request and plays the role of the HTTP/HTTPS client (with HTTP as selected
                transport) and Node A plays the role of the HTTP/HTTPS server.</t>

            <t> The <pushMappingsRequest> exchange allows a LoST Sync source to push mappings
                to LoST Sync destination. The assumption is being made that Node A and B have
                previously been configured in a way that they push mappings in such a fashion and
                that Node A maintains state about the mappings have to be pushed to Node B. No
                subscribe mechanism is defined in this document that would allow Node B to tell Node
                A about what mappings it is interested nor a mechanism for learning to which
                entities mappings have to be pushed. <figure anchor="overview2"
                    title="Pushing Mappings with a <pushMappingsRequest> Message">
                    <artwork><![CDATA[
    +---------+                   +---------+
    | Node A  |                   | Node B  |
    | acting  |                   | acting  |
    | as      |                   | as      |
    | LoST    |                   | LoST    |
    | Sync    |                   | Sync    |
    | Source  |                   | Dest.   |
    +---------+                   +---------+
        |                              |
        |                              |
        |                              |
        | <pushMappingsRequest>        |
        |----------------------------->|
        |                              |
        | <pushMappingsResponse>       |
        |<-----------------------------|
        |                              |
        |                              |
        |                              |
]]></artwork>
                </figure>
            </t>
            <t>Note that in the exchange illustrated in <xref target="overview2"/> Node A issuing
                the first request and plays the role of the HTTP/HTTPS client (with HTTP as selected
                transport) and Node B plays the role of the HTTP/HTTPS server.</t>
        </section>

        <!-- ******************************************************************************** -->

        <section anchor="terminology" title="Terminology">
            <t>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 RFC 2119 <xref target="RFC2119"/>.</t>

            <t>This document reuses terminology introduced by the <xref
                    target="I-D.ietf-ecrit-mapping-arch">mapping architecture document</xref>.</t>

            <t>Throughout this document we use the term LoST Sync source and LoST Sync destination
                to denote the protocol end points of the exchange. The protocol is referred as LoST
                Sync within the text.</t>
        </section>

        <!-- ******************************************************************************** -->

        <section anchor="query"
            title="Querying for Mappings with a <getMappingsRequest> / <getMappingsResponse> Exchange ">

            <section title="Behavior of the LoST Sync Source">

                <t>A LoST Sync destination has two ways to retrieve mapping elements from a LoST
                    Sync source. </t>
                <t>
                    <list style="numbers">
                        <t>A mechanisms that is suitable when no mappings are available on the LoST
                            Sync destination is to submit an empty <getMappingsRequest>
                            message, as shown in <xref target="empty-request"/>. The intent by the
                            LoST Sync destination thereby is to retrieve all mappings from the LoST
                            Sync source. Note that the request does not propagate further to other
                            nodes.</t>

                        <t>In case a LoST Sync destination node has already obtained mappings in
                            previous exchanges then it may want to check whether these mappings have
                            been updated in the meanwhile. The policy when to poll for updated
                            mapping information is outside the scope of this document. The
                            <getMappingsRequest> message with one or multiple
                            <exists> child element(s) allows to reduce the number of
                            returned mappings to those that have been updated and also to those that
                            are missing. </t>
                    </list>
                </t>

                <t>In response to the <getMappingsRequest> message the LoST Sync destination
                    waits for the <getMappingsResponse> message. In case of a successful
                    response the LoST Sync destination stores the received mappings and determines
                    which mappings to replace.</t>
            </section>

            <section title="Behavior of the LoST Sync Source">

                <t>When a LoST Sync source receives an empty <getMappingsRequest> message
                    then all locally available mappings MUST be returned.</t>

                <t>When a LoST Sync source receives a <getMappingsRequest> message with one
                    or multiple <exists> child element(s) then it MUST consult with
                    the local mapping database to determine whether any of the mappings of the
                    client is stale and whether there are mappings locally that the client does not
                    yet have. The former can be determined by finding mappings corresponding to the
                    'source' and 'sourceID' attribut where a mapping with a more recent lastUpdated
                    date exists. </t>

                <t>Processing a <getMappingsRequest> message MAY lead to a successful
                    response in the form of a <getMappingsResponse> or an <errors>
                    message. Only the <badRequest>, <forbidden>,
                    <internalError>, <serverTimeout> errors, defined in <xref
                        target="RFC5222"/>, are utilized by this specification. Neither the
                    <redirect> nor the <warnings> messages are reused by this
                message.</t>
            </section>

            <section title="Examples">

                <t>The first example shows an empty <getMappingsRequest> message that would
                    retrieve all locally stored mappings at the LoST Sync source. <figure
                        anchor="empty-request"
                        title="Example of empty <getMappingsRequest> message">
                        <artwork><![CDATA[
<?xml version="1.0" encoding="UTF-8"?>
<getMappingsRequest xmlns="urn:ietf:params:xml:ns:lostsync1"/> 
]]></artwork>
                    </figure>
                </t>

                <t>A further example request is shown in <xref target="getMappings"/> and the
                    corresponding response is depicted in <xref target="getMappingsResponse"/>. In
                    this example a request is made for a specific mapping (with
                    source="authoritative.bar.example" and
                    sourceId="7e3f40b098c711dbb6060800200c9a66") that is more recent than
                    "2006-11-01T01:00:00Z". </t>

                <t>
                    <figure anchor="getMappings" title="Example <getMappingsRequest> Message">
                        <artwork><![CDATA[
<?xml version="1.0" encoding="UTF-8"?>
<getMappingsRequest xmlns="urn:ietf:params:xml:ns:lostsync1">
    <exists>
        <mapping-fingerprint source="authoritative.bar.example"
        sourceId="7e3f40b098c711dbb6060800200c9a66"
        lastUpdated="2006-11-01T01:00:00Z">
        </mapping-fingerprint>
    </exists>
</getMappingsRequest>

]]></artwork>
                    </figure>
                </t>
                <t>The response to the above request is shown in <xref target="getMappingsResponse"
                    />. A more recent mapping was available with the identification of
                    source="authoritative.bar.example" and
                    sourceId="7e3f40b098c711dbb6060800200c9a66". Only one mapping that matched
                    source="authoritative.foo.example" was found and returned. </t>
                <t>
                    <figure anchor="getMappingsResponse"
                        title="Example <getMappingsResponse> Message">
                        <artwork><![CDATA[
<?xml version="1.0" encoding="UTF-8"?>
<sync:getMappingsResponse 
    xmlns:sync="urn:ietf:params:xml:ns:lostsync1"
    xmlns="urn:ietf:params:xml:ns:lost1"
    xmlns:p2="http://www.opengis.net/gml">
    
        <mapping source="authoritative.bar.example"
            sourceId="7e3f40b098c711dbb6060800200c9a66"
            lastUpdated="2008-11-26T01:00:00Z"
            expires="2009-12-26T01:00:00Z">
            <displayName xml:lang="en"> 
                Leonia Police Department
            </displayName>
            <service>urn:service:sos.police</service>
            <serviceBoundary
profile="urn:ietf:params:lost:location-profile:basic-civic">
                <civicAddress
xmlns="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr">
                    <country>US</country>
                    <A1>NJ</A1>
                    <A3>Leonia</A3>
                    <PC>07605</PC>
                </civicAddress>
            </serviceBoundary>
            <uri>sip:police@leonianj2.example.org</uri>
            <serviceNumber>911</serviceNumber>
        </mapping>
        
        <mapping expires="2009-01-01T01:44:33Z"
            lastUpdated="2008-11-01T01:00:00Z"
            source="authoritative.foo.example"
            sourceId="7e3f40b098c711dbb606011111111111">
            <displayName xml:lang="en"> 
                New York City Police Department
            </displayName>
            <service>urn:service:sos.police</service>
            <serviceBoundary profile="geodetic-2d">
                <p2:Polygon srsName="urn:ogc:def::crs:EPSG::4326">
                    <p2:exterior>
                        <p2:LinearRing>
                            <p2:pos>37.775 -122.4194</p2:pos>
                            <p2:pos>37.555 -122.4194</p2:pos>
                            <p2:pos>37.555 -122.4264</p2:pos>
                            <p2:pos>37.775 -122.4264</p2:pos>
                            <p2:pos>37.775 -122.4194</p2:pos>
                        </p2:LinearRing>
                    </p2:exterior>
                </p2:Polygon>
            </serviceBoundary>
            <uri>sip:nypd@example.com</uri>
            <uri>xmpp:nypd@example.com</uri>
            <serviceNumber>911</serviceNumber>
        </mapping>
    
</sync:getMappingsResponse>
]]></artwork>
                    </figure>
                </t>
            </section>
        </section>


        <!-- ******************************************************************************** -->

        <section
            title="Pushing Mappings via <pushMappings> and
<pushMappingsResponse>">

            <section title="Behavior of the LoST Sync Source">

                <t>When a LoST Sync source obtains new information that is of interest to its peers,
                    it may push the new mappings to its peers. Configuration settings at both peers
                    decide whether this functionality is used and what mappings are pushed to which
                    other peers. New mappings may arrive through various means, such as a manual
                    addition to the local mapping database, or through the interaction with other
                    entities. Deleting mappings may also trigger a protocol interaction.</t>

                <t>The LoST Sync source SHOULD keep track to which LoST Sync destination it has
                    pushed mapping elements. If it does not keep state information then it always
                    has to push the complete data set. As discussed in Section 5.1 of <xref
                        target="RFC5222"/>, mapping elements are identified by the 'source',
                    'sourceID' and 'lastUpdated' attributes. A mapping is considered the same if
                    these three attributes match. It is RECOMMENDED not to push the same information
                    to the same peer more than once.</t>

                <t>A <pushMappings> request sent by a LoST Sync source MUST containing one or
                    more <mapping> elements. </t>
                <t>To delete a mapping, the content of the mapping is left empty. The node can
                    delete the mapping from its internal mapping database, but has to remember which
                    peers it has distributed this update to. The 'expires' attribute is required,
                    but ignored. If an attempt is made to delete a non-existent mapping, the request
                    is silently ignored.</t>
            </section>
            <section title="Behavior of the LoST Sync Destination">
                <t>When a LoST Sync destination receives a <pushMappingsRequest> message then
                    a newly received mapping M' MUST replace an existing mapping M if all of the
                    following conditions hold: <list style="numbers">
                        <t>M'.source equals M.source</t>
                        <t>M'.sourceID' equals M.sourceID</t>
                        <t>M'.lastUpdated is greater than M.lastUpdated</t>
                    </list>
                </t>
                <t>If the received mapping M' does not update any existing mapping M then it MUST be
                    added to the local cache as an independent mapping.</t>
                <t>If a <pushMappingsRequest> message with an empty <mapping>
                    element is received then a corresponding mapping has to be determined based on
                    the 'source', 'sourceID' and 'lastUpdated' attributes. If a mapping has been
                    found then it MUST be deleted. If no mapping can be identified then an
                    <errors> response MUST be returned that contains the <notDeleted>
                    child element. The <notDeleted> element MAY carry a
                    <message> element and MUST contain the <mapping>
                    element(s) that caused the error.</t>
                <t>The response to a <pushMappingsRequest> request is a
                    <pushMappingsResponse> message. With this specification, a successful
                    response message returns no additional elements, whereas an <errors>
                    response is returned in the response message, if the request failed. Only the
                    <badRequest>, <forbidden>, <internalError> or
                    <serverTimeout> errors defined in Section 13.1 of <xref target="RFC5222"
                    />, are used. The <redirect> and <warnings> messages are not used
                    for this query/response.</t>

                <t>If the set of nodes that are synchronizing their data does not form a tree, it is
                    possible that the same information arrives through several other nodes. This is
                    unavoidable, but generally only imposes a modest overhead. (It would be possible
                    to create a spanning tree in the same fashion as IP multicast, but the
                    complexity does not seem warranted, given the relatively low volume of
                data.)</t>
            </section>

            <section title="Example">
                <t> An example is shown in <xref target="pushMappings"/>. Image a LoST node that
                    obtained two new mappings identified as follows: <list style="symbols">
                        <t> source="authoritative.example"
                            sourceId="7e3f40b098c711dbb6060800200c9a66"
                            lastUpdated="2008-11-26T01:00:00Z" </t>
                        <t>source="authoritative.example"
                            sourceId="7e3f40b098c711dbb606011111111111"
                            lastUpdated="2008-11-01T01:00:00Z" </t>
                    </list>
                </t>
                <t> These two mappings have to be added to the peer's mapping database. </t>
                <t> Additionally, the following mapping has to be deleted: <list style="symbols">
                        <t> source="nj.us.example" sourceId="123" lastUpdated="2008-11-01T01:00:00Z"
                        </t>
                    </list>
                </t>

                <t>
                    <figure anchor="pushMappings"
                        title="Example <pushMappingsRequest> Message">
                        <artwork><![CDATA[
<?xml version="1.0" encoding="UTF-8"?>
<sync:pushMappingsRequest 
    xmlns:sync="urn:ietf:params:xml:ns:lostsync1"
    xmlns="urn:ietf:params:xml:ns:lost1"
    xmlns:p2="http://www.opengis.net/gml">
            
        <mapping source="authoritative.example"
            sourceId="7e3f40b098c711dbb6060800200c9a66"
            lastUpdated="2008-11-26T01:00:00Z"
            expires="2009-12-26T01:00:00Z">
            <displayName xml:lang="en"> 
                Leonia Police Department
            </displayName>
            <service>urn:service:sos.police</service>
            <serviceBoundary
     profile="urn:ietf:params:lost:location-profile:basic-civic">
                <civicAddress
     xmlns="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr">
                    <country>US</country>
                    <A1>NJ</A1>
                    <A3>Leonia</A3>
                    <PC>07605</PC>
                </civicAddress>
            </serviceBoundary>
            <uri>sip:police@leonianj.example.org</uri>
            <serviceNumber>911</serviceNumber>
        </mapping>
        
        <mapping expires="2009-01-01T01:44:33Z"
            lastUpdated="2008-11-01T01:00:00Z"
            source="authoritative.example"
            sourceId="7e3f40b098c711dbb606011111111111">
            <displayName xml:lang="en"> 
                New York City Police Department
            </displayName>
            <service>urn:service:sos.police</service>
            <serviceBoundary profile="geodetic-2d">
                <p2:Polygon srsName="urn:ogc:def::crs:EPSG::4326">
                    <p2:exterior>
                        <p2:LinearRing>
                            <p2:pos>37.775 -122.4194</p2:pos>
                            <p2:pos>37.555 -122.4194</p2:pos>
                            <p2:pos>37.555 -122.4264</p2:pos>
                            <p2:pos>37.775 -122.4264</p2:pos>
                            <p2:pos>37.775 -122.4194</p2:pos>
                        </p2:LinearRing>
                    </p2:exterior>
                </p2:Polygon>
            </serviceBoundary>
            <uri>sip:nypd@example.com</uri>
            <uri>xmpp:nypd@example.com</uri>
            <serviceNumber>911</serviceNumber>
        </mapping>
        
        <mapping source="nj.us.example" 
            sourceId="123"
            lastUpdated="2008-11-01T01:00:00Z"
            expires="2008-11-01T01:00:00Z"/>
    
</sync:pushMappingsRequest>
]]></artwork>
                    </figure>
                </t>

                <t>In response, the peer performs the necessary operation and updates its mapping
                    database. In particular, it will check whether the other peer is authorized to
                    perform the update and whether the elements and attributes contain values that
                    it understands. In our example, a positive response is returned as shown in
                        <xref target="pushMappingsResponse"/>.</t>

                <t>
                    <figure anchor="pushMappingsResponse"
                        title="Example <pushMappingsResponse>">
                        <artwork><![CDATA[
<?xml version="1.0" encoding="UTF-8"?>
<pushMappingsResponse xmlns="urn:ietf:params:xml:ns:lostsync1" />
]]></artwork>
                    </figure>
                </t>

                <t>In case that a mapping could not be deleted as requested the following error
                    response might be returned instead. <figure anchor="error"
                        title="Example <errors> Message">
                        <artwork><![CDATA[
<?xml version="1.0" encoding="UTF-8"?>
<errors xmlns="urn:ietf:params:xml:ns:lost1"
    xmlns:sync="urn:ietf:params:xml:ns:lostsync1" 
    source="nodeA.example.com">

    <sync:notDeleted 
        message="Could not delete the indicated mapping." 
        xml:lang="en"> 
        
        <mapping source="nj.us.example" 
            sourceId="123"
            lastUpdated="2008-11-01T01:00:00Z"
            expires="2008-11-01T01:00:00Z"/>
        
    </sync:notDeleted>
</errors>
]]></artwork>
                    </figure>
                </t>
            </section>
        </section>

        <!-- ******************************************************************************** -->

        <section title="Transport">
            <t> LoST Sync needs an underlying protocol transport mechanism to carry requests and
                responses. This document defines an XML protocol over HTTP and over HTTP-over-TLS.
                Client and server developers are reminded that full support of RFC 2616 HTTP
                facilities is expected. If clients or servers re-implement HTTP, rather than using
                available servers or client code as a base, careful attention must be paid to full
                interoperability. Other transport mechanisms are left to future documents. The
                selection of the transport mechanism will in most cases be determined through manual
                configuration although the usage of the U-NAPTR application defined in the LoST
                specification is possible. In protocols that support content type indication, LoST
                Sync uses the media type application/lostsync+xml.</t>

            <t>When using HTTP <xref target="RFC2616"/> and HTTP-over-TLS <xref target="RFC2818"/>,
                LoST Sync messages use the HTTP POST method. The HTTP request MUST use the
                Cache-Control response directive "no-cache" to HTTP-level caching even by caches
                that have been configured to return stale responses to client requests.</t>


            <t>All LoST Sync responses, including those indicating a LoST warning or error, are
                carried in 2xx responses, typically 200 (OK). Other 2xx responses, in particular 203
                (Non-authoritative information) may be returned by HTTP caches that disregard the
                caching instructions. 3xx, 4xx and 5xx HTTP response codes indicates that the HTTP
                request itself failed or was redirected; these responses do not contain any LoST
                Sync XML elements. </t>

        </section>

        <!-- ******************************************************************************** -->

        <section anchor="schema" title="RelaxNG">
            <t>
                <figure>
                    <artwork><![CDATA[
<?xml version="1.0" encoding="utf-8"?>
 
     <grammar ns="urn:ietf:params:xml:ns:lostsync1"
     xmlns="http://relaxng.org/ns/structure/1.0"
     xmlns:a="http://relaxng.org/ns/compatibility/annotations/1.0"
     datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
         
         <include href="lost.rng"/>
         
         <start combine="choice">
             
          <a:documentation> Location-to-Service Translation (LoST)
            Synchronization Protocol</a:documentation>
             
             <choice>
                 <ref name="pushMappings"/>
                 <ref name="pushMappingsResponse"/>
                 <ref name="getMappingsRequest"/>
                 <ref name="getMappingsResponse"/>
             </choice>
         </start>
         
         
         <define name="pushMappings">
             <element name="pushMappings">
                     <oneOrMore>
                         <ref name="mapping"/>
                     </oneOrMore>
                 
                 <ref name="extensionPoint"/>
             </element>
         </define>
         
         <define name="pushMappingsResponse">
             <element name="pushMappingsResponse">
                 <ref name="extensionPoint"/>
             </element>
         </define>
         
          <define name="getMappingsRequest">
               <element name="getMappingsRequest">
                 <choice>
                      <ref name="exists"></ref>
                      <ref name="extensionPoint"/>
                 </choice>
             </element>
         </define>
         
          <define name="exists">
               <element name="exists">
                    <oneOrMore>
                         <element name="mapping-fingerprint">
                              <attribute name="source">
                                   <data type="token"/>
                              </attribute>
                              <attribute name="sourceId">
                                   <data type="token"/>
                              </attribute>
                              <attribute name="lastUpdated">
                                   <data type="dateTime"/>
                              </attribute>
                              <ref name="extensionPoint"/>
                         </element>
                    </oneOrMore>
               </element>
          </define>
                    
         <define name="getMappingsResponse">
             <element name="getMappingsResponse">
                     <oneOrMore>
                         <ref name="mapping"/>
                     </oneOrMore>                 
                 <ref name="extensionPoint"/>
             </element>
         </define>         
         
          <!-- error messages --> 
          
          <define name="notDeleted">
               <element name="notDeleted">
                    <ref name="basicException"/>
                    <oneOrMore>
                         <ref name="mapping"/>
                    </oneOrMore>
               </element>
          </define>
     </grammar>
	]]></artwork>
                </figure>
            </t>
        </section>

        <!-- ******************************************************************************** -->

        <section title="Security Considerations">
            <t>This document defines a protocol for exchange of mapping information between two
                entities. Hence, the operations described in this document involve mutually-trusting
                LoST nodes. These nodes need to authenticate each other, using mechanisms such as
                    <xref target="RFC2617">HTTP Digest</xref>, <xref target="RFC2617">HTTP
                Basic</xref> over <xref target="RFC5246">TLS</xref> or TLS client and server
                certificates. Manual configuration for the setup of the peering relationships is
                required and hence the choice of the security mechanisms used between the two
                entities is a deployment specific decision. In any case, it MUST be ensured that the
                two end points are authenticated and that a secure communication channel (i.e., an
                integrity protected exchange of data with the help of the TLS Record Layer) is setup
                to avoid the possibility of injecting bogus mappings. If an adversary manages to
                inject false mappings then this could lead to denial of service attacks. If the
                mapping data contains a URL that does not exist then emergency services for the
                indicated area are not reachable. If all mapping data contains URLs that point to a
                single PSAP (rather than a large number) then this PSAP is likely to experience
                overload conditions. If the mapping data contains a URL that points to a server
                controlled by the adversary itself then it might impersonate PSAPs.</t>
        </section>

        <!-- ******************************************************************************** -->

        <section title="IANA Considerations">

            <section title="Content-type registration for 'application/lostsync+xml'">

                <t>This specification requests the registration of a new MIME type according to the
                    procedures of RFC 4288 <xref target="RFC4288"/> and guidelines in RFC 3023 <xref
                        target="RFC3023"/>.</t>

                <t>
                    <list style="hanging">
                        <t hangText="MIME media type name:">application <vspace blankLines="1"/>
                        </t>

                        <t hangText="MIME subtype name:">lostsync+xml <vspace blankLines="1"/>
                        </t>

                        <t hangText="Mandatory parameters:">none<vspace blankLines="1"/>
                        </t>

                        <t hangText="Optional parameters:">charset<vspace blankLines="1"/> Indicates
                            the character encoding of enclosed XML.<vspace blankLines="1"/>
                        </t>

                        <t hangText="Encoding considerations:"> Uses XML, which can employ 8-bit
                            characters, depending on the character encoding used. See RFC 3023 <xref
                                target="RFC3023"/>, Section 3.2.<vspace blankLines="1"/></t>

                        <t hangText="Security considerations:"> This content type is designed to
                            carry LoST Syncronization protocol payloads.<vspace blankLines="1"/></t>

                        <t hangText="Interoperability considerations:">None<vspace blankLines="1"
                                /><vspace blankLines="1"/></t>

                        <t hangText="Published specification:">RFCXXXX [NOTE TO IANA/RFC-EDITOR:
                            Please replace XXXX with the RFC number of this specification.]<vspace
                                blankLines="1"/>
                        </t>

                        <t hangText="Applications which use this media type:"> Emergency and
                            Location-based Systems<vspace blankLines="1"/>
                        </t>

                        <t hangText="Additional information:">
                            <list style="hanging">
                                <t hangText="Magic Number:">None<vspace blankLines="1"/>
                                </t>

                                <t hangText="File Extension:">.lostsyncxml<vspace blankLines="1"/>
                                </t>

                                <t hangText="Macintosh file type code:">'TEXT'<vspace blankLines="1"
                                    />
                                </t>
                            </list>
                        </t>

                        <t hangText="Personal and email address for further information:">Hannes
                            Tschofenig, Hannes.Tschofenig@nsn.com<vspace blankLines="1"/>
                        </t>

                        <t hangText="Intended usage:">LIMITED USE<vspace blankLines="1"/>
                        </t>

                        <t hangText="Author:">
                            <vspace blankLines="1"/> This specification is a work item of the IETF
                            ECRIT working group, with mailing list address
                                <ecrit@ietf.org>.<vspace blankLines="1"/>
                        </t>
                        <t hangText="Change controller:">
                            <vspace blankLines="1"/>The IESG <iesg@ietf.org> </t>
                    </list>
                </t>
            </section>

            <section title="LoST Sync Relax NG Schema Registration">

                <t>
                    <list style="hanging">
                        <t hangText="URI:">urn:ietf:params:xml:schema:lostsync1</t>
                        <t hangText="Registrant Contact:">IETF ECRIT Working Group, Hannes
                            Tschofenig (Hannes.Tschofenig@gmx.net).</t>
                        <t hangText="Relax NG Schema:">The Relax NG schema to be registered is
                            contained in <xref target="schema"/>. </t>
                    </list>
                </t>
            </section>



            <section title="LoST Synchronization Namespace Registration">
                <t>
                    <list style="hanging">
                        <t hangText="URI:">urn:ietf:params:xml:ns:lostsync1</t>

                        <t hangText="Registrant Contact:">IETF ECRIT Working Group, Hannes
                            Tschofenig (Hannes.Tschofenig@gmx.net).</t>

                        <t hangText="XML:">
                            <figure>
                                <artwork><![CDATA[
BEGIN
<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
  "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
  <meta http-equiv="content-type"
        content="text/html;charset=iso-8859-1"/>
  <title>LoST Synchronization Namespace</title>
</head>
<body>
  <h1>Namespace for LoST server synchronization</h1>
  <h2>urn:ietf:params:xml:ns:lost1:sync</h2>
<p>See <a href="[URL of published RFC]">RFCXXXX
    [NOTE TO IANA/RFC-EDITOR:
     Please replace XXXX with the RFC number of this
    specification.]</a>.</p>
</body>
</html>
END
]]></artwork>
                            </figure>
                        </t>
                    </list>
                </t>
            </section>


        </section>

        <!-- ******************************************************************************** -->

        <section title="Acknowledgments">
            <t>Robins George, Cullen Jennings, Karl Heinz Wolf, Richard Barnes, Mayutan Arumaithurai
                and Andrew Newton provided helpful input. Jari Urpalainen assisted with the Relax NG
                schema. We would also like to thank our PROTO shepherd Roger Marshall for his help
                with the document.</t>
        </section>

        <!-- ******************************************************************************** -->

    </middle>
    <back>

        <references title="Normative References"> &rfc2119; &rfc2617; &rfc5222;
            &rfc5246; &RFC3023; &RFC4288; &RFC2616; &RFC2818; </references>

        <references title="Informative References"> &I-D.ietf-ecrit-mapping-arch; </references>

    </back>
</rfc>

PAFTECH AB 2003-20262026-04-23 04:32:19