ecrit B. Rosen
Internet-Draft October 23, 2018
Intended status: Standards Track
Expires: April 26, 2019
Validation of Locations Around a Planned Change
draft-ietf-ecrit-lost-planned-changes-02
Abstract
This document defines an extension to LoST (RFC5222) that allows a
planned change to the data in the LoST server to occur. Records that
previously were valid will become invalid at a date in the future,
and new locations will become valid after the date. The extension
adds two elements to the <findservice> request: A URI to be used to
inform the LIS that previously valid locations will be invalid after
the planned change date, and add a date which requests the server to
perform validation as of the date specified. It also adds an
optional Time-To-Live element to the response, which informs clients
about the current expected lifetime of the validation. This document
also provides a conventional XML schema for LoST, as backwards
compatible alternative to the RelaxNG schema in RFC5222
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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."
This Internet-Draft will expire on April 26, 2019.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 4
3. <plannedChange> element . . . . . . . . . . . . . . . . . . . 4
4. <locationInvalidated> object . . . . . . . . . . . . . . . . 4
5. URI Not Stored Warning . . . . . . . . . . . . . . . . . . . 5
6. Time-To-Live (TTL) in Response . . . . . . . . . . . . . . . 5
7. Replacement XML schema . . . . . . . . . . . . . . . . . . . 6
8. Extension XML schema . . . . . . . . . . . . . . . . . . . . 14
9. Security Considerations . . . . . . . . . . . . . . . . . . . 15
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
10.1. Replacement Schema Registration . . . . . . . . . . . . 16
10.2. Replacement Schema Registration . . . . . . . . . . . . 16
10.3. LoST Namespace Registration . . . . . . . . . . . . . . 16
11. Normative References . . . . . . . . . . . . . . . . . . . . 17
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
This document describes an update to the LoST protocol + which allows
a <findservice> request to optionally add a URI and a date to be used
with planned changes to the underlying location information in the
server. The URI is retained by the LoST server, associated with the
data record that was validated, and used to notify the LIS (the LoST
client) when a location which was previously valid will become
invalid. The date is used by the client to ask the server to perform
validation as of a future date. In addition to this mechanism, the
<findserviceResponse> is also extended to provide a Time-To-Live
(TTL) for validation, after which the client should revalidate the
location.
Validation of civic locations involves dealing with data that changes
over time. A typical example is a portion of a county or province
that was not part of a municipality is "annexed" to a municipality.
Prior to the change, the content of the PIDF-LO A3 element would be
blank, or represent some other value and after the change would be
the municipality that annexed that part of the county/province. This
kind of annexation has an effective date and time (typically 00:00 on
the first or last day of a month).
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Records in a LIS must change around these kinds of events. The old
record must be discarded, and a new, validated record must be loaded
into the LIS. It is often difficult for the LIS operator to know
that records must be changed around such events. There are other
circumstances where locations that were previously valid become
invalid, such as a street renaming or renumbering event. As RFC5222
defines validation, the only way for a LIS to discover such changes
was to periodically revalidate its entire database. Of course, this
would not facilitate timely changes, is not coordinated with the
actual change event, and also adds significant load to the LoST
server. Even if re-validation is contemplated, the server has no
mechanism to control, or even suggest the time period for
revalidation
This extension allows the client to provide a stable URI that is
retained by the server associated with the location information used
in the request. In the event of a planned change, or any other
circumstance where the location becomes invalid, the server sends a
notification to the URI informing it of a change. The notification
contains the date and time when the location becomes invalid.
Ideally, following such a notification, the LIS will prepare a new
record to be inserted in its active database, that becomes active at
the precise planned event date and time, at which point it would also
delete the old record. However, the new record has to be valid, and
the LIS would like to validate it prior to the planned change event.
If it requests validation before the planned event, the server
(without this extension) would inform the client that the location
was invalid. This extension includes an optional "as of" date and
time in the request that allows the LoST server to provide validation
as of the date and time specified, as opposed to the "as of now"
implied in the current LoST protocol.
When it is not practical or advisable for the LIS to maintain stable
URIs for all of its records, periodic revalidation can be still used
to maintain the data in the LIS. However, the server should be able
to control the rate of such revalidation. For this purpose, a new
TTL element is included in the <findserviceResponse> which provides
advice from the server to the LIS of when validation is suggested.
There are quite a few implementations of LoST. Experience with these
implementations indicates that the RelaxNG schema is very difficult
to deal with, because the tools that the implementors use don't
support it, and their staff is unfamiliar with it. Alternative
schemas have been circulated, which is undesirable, as they may not
be in conformance to the RelaxNG schema in [RFC5222]. This document
provides an XML schema that replaces the RelaxNG schema. It can be
used by any implementation interchangeably with the RelaxNG schema.
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2. Conventions used in this document
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 [RFC2119].
"Server" in this document refers to the LoST server and "Client" is
the LoST client, even when the server is performing an operation on
the client.
3. <plannedChange> element
This document defines a new element to <findService> called
"plannedChange". This element contains two attributes: 'uri' and
'asOf'. The 'uri' attribute MUST be a URI with a scheme of HTTPS.
The URI will be stored by the server against the location in the
request for subsequent use with the notification function defined
below. To minimize storage requirements of at the server, the length
of the URI MUST be 256 bytes or less. Each client of the server may
only store one URI against a location, where "location" is defined by
policy at the server, since a given unique location may have many
combinations of location elements that resolve to the same location.
If the server receives a 'uri' for the same location from the same
client, the URI in the request replaces the URI it previously
retained. Policy at the server may limit how many URIs it retains
for a given location. A new warning is defined below to be used to
indicate that the URI has not been stored. If the location in the
request is invalid, the URI will not be stored and the warning will
be returned.
The 'asOf' attribute contains a date and time. The server will
validate the location in the request as of the date specified, taking
into account planned changes. This allows the client to verify that
it can make changes in the LIS commensurate with changes in the LoST
server by validating locations in advance of a change.
4. <locationInvalidated> object
When the server needs to invalidate a location where the client
provided a URI in <plannedChange>, the server executes an HTTPS POST
containing <locationInvalidated> to the URI previously provided.
This is the notice from the server to the client that the location
may be invalid and should be revalidated. <locationInvalidated>
contains an 'invalidAsOf' attribute that specifies when the location
may become invalid. If the date/time in 'invalidAsOf' is earlier
than the time the <locationInvalidated> was sent, the location may
already be invalid and the LIS should take immediate action. If the
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POST operation fails, the server MAY retry the operation immediately,
and if it fails again, retry the operation at a later time.
5. URI Not Stored Warning
A new warning is added to the exceptionContainer, 'uriNotStored'.
This warning MUST NOT be returned unless the <plannedChange> element
was found in the corresponding request. The warning is returned when
the server decides not to store the URI found in the <plannedChange>
element. As discussed above, this may occur because, among other
reasons, the policy at the server limits how many URIs will be stored
against a specific location, the URI is not well formed or the policy
at the server has some other restriction on the feature.
6. Time-To-Live (TTL) in Response
A new <ttl> element is added to the <findserviceResponse>. The <ttl>
element contains a date and time after which the client may wish to
revalidate the location at the server. This element MAY be added by
the server if validation is requested in the response. The form of
the element is the 'expires' attribute pattern, which allows explicit
'NO CACHE' and 'NO EXPIRATION' values to be returned in the <ttl>
element. 'NO CACHE' has no meaning and MUST NOT be returned in TTL.
'NO EXPIRATION' means the server does not have any suggested
revalidation period.
Selecting a revalidation interval is a complex balancing of
timeliness, server load, stability of the underlying data, and policy
of the LoST server. Too short, and load on the server may overwhelm
it. Too long and invalid data may persist in the server for too
long. The URI mechanism provides timely notice to coordinate
changes, but even with it, it is often advisable to revalidate data
eventually.
In areas that have little change in data, such as fully built out,
stable communities already part of a municipality, it may be
reasonable to set revalidation periods of 6 months or longer,
especially if the URI mechanism is widely deployed at both the server
and the clients. In areas that are quickly growing, 20-30 day
revalidation may be more appropriate even though such revalidation
would be the majority of the traffic on the LoST server.
When a planned change is made, typically the TTL value for the
affected records is lowered, so that revalidation is forced soon
after the change is implemented. It is not advisable to set the
expiration precisely at the planned change time if a large number of
records will be changed, since that would cause a large spike in
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traffic at the change time. Rather, the expiration time should have
a random additional time added to it to spread out the load.
7. Replacement XML schema
The Relax NG schema in [RFC5222] is replaced with the following XML
schema:
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns="urn:ietf:params:xml:ns:lost1"
targetNamespace="urn:ietf:params:xml:ns:lost1"
elementFormDefault="qualified">
<xs:element name="findService">
<xs:complexType>
<xs:sequence>
<xs:group ref="requestLocation"/>
<xs:group ref="commonRequestPattern"/>
</xs:sequence>
<xs:attribute name="validateLocation" type="xs:boolean"/>
<xs:attribute name="serviceBoundary">
<xs:simpleType>
<xs:restriction base="xs:token">
<xs:enumeration value="reference"/>
<xs:enumeration value="value"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="recursive" type="xs:boolean"/>
</xs:complexType>
</xs:element>
<xs:element name="listServices">
<xs:complexType>
<xs:group ref="commonRequestPattern"/>
</xs:complexType>
</xs:element>
<xs:element name="listServicesByLocation">
<xs:complexType>
<xs:sequence>
<xs:group ref="requestLocation"/>
<xs:group ref="commonRequestPattern"/>
</xs:sequence>
<xs:attribute name="recursive" type="xs:boolean"/>
</xs:complexType>
</xs:element>
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<xs:element name="getServiceBoundary">
<xs:complexType>
<xs:group ref="extensionPoint"/>
<xs:attributeGroup ref="serviceBoundaryKey"/>
</xs:complexType>
</xs:element>
<xs:element name="findServiceResponse">
<xs:complexType>
<xs:sequence>
<xs:element ref="mapping" maxOccurs="unbounded"/>
<xs:element ref="locationValidation" minOccurs="0"/>
<xs:group ref="commonResponsePattern"/>
<xs:group ref="locationUsed"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="listServicesResponse">
<xs:complexType>
<xs:sequence>
<xs:element ref="serviceList"/>
<xs:group ref="commonResponsePattern"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="listServicesByLocationResponse">
<xs:complexType>
<xs:sequence>
<xs:element ref="serviceList"/>
<xs:group ref="commonResponsePattern"/>
<xs:group ref="locationUsed"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="getServiceBoundaryResponse">
<xs:complexType>
<xs:sequence>
<xs:group ref="serviceBoundary"/>
<xs:group ref="commonResponsePattern"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:group name="commonRequestPattern">
<xs:sequence>
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<xs:group ref="service"/>
<xs:element ref="path" minOccurs="0"/>
<xs:group ref="extensionPoint"/>
</xs:sequence>
</xs:group>
<xs:group name="commonResponsePattern">
<xs:sequence>
<xs:element ref="warnings" minOccurs="0" maxOccurs="unbounded"/>
<xs:element ref="path"/>
<xs:group ref="extensionPoint"/>
</xs:sequence>
</xs:group>
<xs:group name="requestLocation">
<xs:sequence>
<xs:element ref="location" maxOccurs="unbounded"/>
</xs:sequence>
</xs:group>
<xs:element name="location">
<xs:complexType>
<xs:complexContent>
<xs:extension base="locationInformation">
<xs:attribute name="id" type="xs:token" use="required"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
</xs:element>
<xs:complexType name="locationInformation">
<xs:group ref="extensionPoint" maxOccurs="unbounded"/>
<xs:attribute name="profile" type="xs:NMTOKEN"/>
</xs:complexType>
<xs:group name="serviceBoundary">
<xs:sequence>
<xs:element ref="serviceBoundary" maxOccurs="unbounded"/>
</xs:sequence>
</xs:group>
<xs:element name="serviceBoundary" type="locationInformation"/>
<xs:element name="serviceBoundaryReference">
<xs:complexType>
<xs:group ref="extensionPoint"/>
<xs:attributeGroup ref="source"/>
<xs:attributeGroup ref="serviceBoundaryKey"/>
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</xs:complexType>
</xs:element>
<xs:attributeGroup name="serviceBoundaryKey">
<xs:attribute name="key" type="xs:token" use="required"/>
</xs:attributeGroup>
<xs:element name="path">
<xs:complexType>
<xs:sequence>
<xs:element ref="via" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="via">
<xs:complexType>
<xs:group ref="extensionPoint"/>
<xs:attributeGroup ref="source"/>
</xs:complexType>
</xs:element>
<xs:group name="locationUsed">
<xs:sequence>
<xs:element ref="locationUsed" minOccurs="0"/>
</xs:sequence>
</xs:group>
<xs:element name="locationUsed">
<xs:complexType>
<xs:attribute name="id" type="xs:token" use="required"/>
</xs:complexType>
</xs:element>
<xs:attributeGroup name="expires">
<xs:attribute name="expires" use="required">
<xs:simpleType>
<xs:union memberTypes="xs:dateTime">
<xs:simpleType>
<xs:restriction base="xs:token">
<xs:enumeration value="NO-CACHE"/>
</xs:restriction>
</xs:simpleType>
<xs:simpleType>
<xs:restriction base="xs:token">
<xs:enumeration value="NO-EXPIRATION"/>
</xs:restriction>
</xs:simpleType>
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</xs:union>
</xs:simpleType>
</xs:attribute>
</xs:attributeGroup>
<xs:simpleType name="qnameList">
<xs:list itemType="xs:QName"/>
</xs:simpleType>
<xs:element name="mapping">
<xs:complexType>
<xs:sequence>
<xs:element ref="displayName"
minOccurs="0" maxOccurs="unbounded"/>
<xs:group ref="service"/>
<xs:choice minOccurs="0">
<xs:group ref="serviceBoundary"/>
<xs:element ref="serviceBoundaryReference"/>
</xs:choice>
<xs:element ref="uri"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element ref="serviceNumber" minOccurs="0"/>
<xs:group ref="extensionPoint"/>
</xs:sequence>
<xs:attributeGroup ref="expires"/>
<xs:attribute name="lastUpdated" type="xs:dateTime"
use="required"/>
<xs:attributeGroup ref="source"/>
<xs:attribute name="sourceId" type="xs:token"
use="required"/>
<xs:attributeGroup ref="message"/>
</xs:complexType>
</xs:element>
<xs:element name="displayName">
<xs:complexType>
<xs:simpleContent>
<xs:extension base="xs:string">
<xs:attribute ref="xml:lang" use="required"/>
</xs:extension>
</xs:simpleContent>
</xs:complexType>
</xs:element>
<xs:element name="uri" type="xs:anyURI"/>
<xs:element name="serviceNumber">
<xs:simpleType>
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<xs:restriction base="xs:token">
<xs:pattern value="[0-9*#]+"/>
</xs:restriction>
</xs:simpleType>
</xs:element>
<xs:element name="locationValidation">
<xs:complexType>
<xs:sequence>
<xs:element ref="valid" minOccurs="0"/>
<xs:element ref="invalid" minOccurs="0"/>
<xs:element ref="unchecked" minOccurs="0"/>
<xs:group ref="extensionPoint"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="valid" type="qnameList"/>
<xs:element name="invalid" type="qnameList"/>
<xs:element name="unchecked" type="qnameList"/>
<xs:complexType name="exceptionContainer">
<xs:sequence>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element ref="badRequest"/>
<xs:element ref="internalError"/>
<xs:element ref="serviceSubstitution"/>
<xs:element ref="defaultMappingReturned"/>
<xs:element ref="forbidden"/>
<xs:element ref="notFound"/>
<xs:element ref="loop"/>
<xs:element ref="serviceNotImplemented"/>
<xs:element ref="serverTimeout"/>
<xs:element ref="serverError"/>
<xs:element ref="locationInvalid"/>
<xs:element ref="locationProfileUnrecognized"/>
</xs:choice>
<xs:group ref="extensionPoint"/>
</xs:sequence>
<xs:attributeGroup ref="source"/>
</xs:complexType>
<xs:element name="errors" type="exceptionContainer"/>
<xs:element name="warnings" type="exceptionContainer"/>
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<xs:complexType name="basicException">
<xs:annotation>
<xs:documentation>
Exception pattern.
</xs:documentation>
</xs:annotation>
<xs:group ref="extensionPoint"/>
<xs:attributeGroup ref="message"/>
</xs:complexType>
<xs:element name="badRequest" type="basicException"/>
<xs:element name="internalError" type="basicException"/>
<xs:element name="serviceSubstitution" type="basicException"/>
<xs:element name="defaultMappingReturned" type="basicException"/>
<xs:element name="forbidden" type="basicException"/>
<xs:element name="notFound" type="basicException"/>
<xs:element name="loop" type="basicException"/>
<xs:element name="serviceNotImplemented" type="basicException"/>
<xs:element name="serverTimeout" type="basicException"/>
<xs:element name="serverError" type="basicException"/>
<xs:element name="locationInvalid" type="basicException"/>
<xs:element name="locationValidationUnavailable"
type="basicException"/>
<xs:element name="locationProfileUnrecognized">
<xs:complexType>
<xs:complexContent>
<xs:extension base="basicException">
<xs:attribute name="unsupportedProfiles"
type="xs:NMTOKENS" use="required"/>
</xs:extension>
</xs:complexContent>
</xs:complexType>
</xs:element>
<xs:element name="redirect">
<xs:complexType>
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<xs:group ref="extensionPoint"/>
<xs:attribute name="target" type="appUniqueString"
use="required"/>
<xs:attributeGroup ref="source"/>
<xs:attributeGroup ref="message"/>
</xs:complexType>
</xs:element>
<xs:attributeGroup name="message">
<xs:attribute name="message" type="xs:token"/>
<xs:attribute ref="xml:lang"/>
</xs:attributeGroup>
<xs:group name="service">
<xs:sequence>
<xs:element ref="service" minOccurs="0"/>
</xs:sequence>
</xs:group>
<xs:element name="service" type="xs:anyURI"/>
<xs:simpleType name="appUniqueString">
<xs:restriction base="xs:token">
<xs:pattern value="([a-zA-Z0-9\-]+\.)+[a-zA-Z0-9]+"/>
</xs:restriction>
</xs:simpleType>
<xs:attributeGroup name="source">
<xs:attribute name="source" type="appUniqueString" use="required"/>
</xs:attributeGroup>
<xs:element name="serviceList">
<xs:simpleType>
<xs:list itemType="xs:anyURI"/>
</xs:simpleType>
</xs:element>
<xs:group name="notLost">
<xs:annotation>
<xs:documentation>
Any element not in the LoST namespace.
</xs:documentation>
</xs:annotation>
<xs:choice>
<xs:any namespace="##other" processContents="skip"/>
<xs:any namespace="##local" processContents="skip"/>
</xs:choice>
</xs:group>
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<xs:group name="anyElement">
<xs:annotation>
<xs:documentation>
A wildcard pattern for including any element
from any other namespace.
</xs:documentation>
</xs:annotation>
<xs:sequence>
<xs:any processContents="skip"
minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
</xs:group>
<xs:attributeGroup name="anyElement">
<xs:annotation>
<xs:documentation>
A wildcard pattern for including any element
from any other namespace.
</xs:documentation>
</xs:annotation>
<xs:anyAttribute processContents="skip"/>
</xs:attributeGroup>
<xs:group name="extensionPoint">
<xs:annotation>
<xs:documentation>
A point where future extensions
(elements from other namespaces)
can be added.
</xs:documentation>
</xs:annotation>
<xs:sequence>
<xs:group ref="notLost"
minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
</xs:group>
</xs:schema>
8. Extension XML schema
This schema provides the extension to the prior section schema for
planned changes:
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<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns="urn:ietf:params:xml:ns:lostPlannedChange1"
targetNamespace="urn:ietf:params:xml:ns:lostPlannedChange1"
elementFormDefault="qualified">
<!-- Import base Lost -->
<xs:import namespace="urn:ietf:params:xml:ns:lost1"/>
<!-- extend the extensionPoint of commonRequestPattern of findService
to include: -->
xs:group ref="plannedChange" minOccurs="1"/>
<!-- where -->
<xs:group name="plannedChange">
<xs:sequence>
<xs:element ref="uri" type="xs:anyURI" />
<xs:element ref="invalidAsOf" type="xs:dateTime" />
<xs:any namespace="##other" processContents="lax"
minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
</xs:group>
<!-- extend the extensionPoint of commonResponsePattern in
findServiceResponse to include: -->
<xs:atttribute name="asOf" type="xs:dateTime" minOccurs="0"/>
<xs:element ref="ttl" type="expires" minOccurs="0" />
<!-- extend the extensionPoint of extensionContainer to include: -->
<xs:element ref="uriNotStored"/>
<!-- where -->
<xs:element name="uriNotStored" type="basicException"/>
</xs:schema>
9. Security Considerations
As an extension to LoST, this document inherits the security issues
raised in [RFC5222]. The server could be tricked into storing a
malicious URI which, when sent the locationInvalidated object could
trigger something untoward. The server MUST NOT accept any data from
the client in response to POSTing the locationInvalidated.
The server is subject to abuse by clients because it is being asked
to store something and may need to send data to an uncontrolled URI.
Clients could request many URIs for the same location for example.
The server MUST have policy that limits use of this mechanism by a
given client. If the policy is exceeded, the server returns the
'uriNotStored' warning. The server MUST validate that the content of
the 'uri' attribute sent is syntactically valid and meets the 256
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bytes limit. When sending the locationInvalidated object to the URI
stored, the server MUST protect itself against common HTTP
vulnerabilities.
The mutual authentication between client and server is RECOMMENDED
for both the initial <findService> operation that requests storing
the URI and the sending of the 'locationInvalidated' object. The
server should be well known to the client, and its credential should
be learned in a reliable way. For example, a public safety system
operating the LoST server may have a credential traceable to a well
known Certificate Authority known to provide credentials for public
safety agencies. Many of the clients will be operated by local ISPs
or other service providers where the server operator can reasonably
obtain a good credential to use for the URI. Where the server does
not recognize the client, its policy MAY limit the use of this
feature beyond what it would limit a client it recognized.
10. IANA Considerations
10.1. Replacement Schema Registration
URI: urn:ietf:params:xml:schema:lost3
Registrant Contact: IETF ECRIT Working Group, Brian Rosen
(br@brianrosen.net).
The XML Schema is found in <xref target="schema"/>.
10.2. Replacement Schema Registration
URI: urn:ietf:params:xml:schema:lostPlannedChange1
Registrant Contact: IETF ECRIT Working Group, Brian Rosen
(br@brianrosen.net).
The XML Schema is found in <xref target="extSchema"100/>.
10.3. LoST Namespace Registration
Rosen Expires April 26, 2019 [Page 16]
Internet-Draft LoST Planned Changes October 2018
URI: urn:ietf:params:xml:ns:lost-plannedChange1
Registrant Contact: IETF ECRIT Working Group, Brian Rosen
(br@brianrosen.net).
XML:
BEGIN
<?xml version="2.0"?>
<!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 Planned Change Namespace</title>
</head>
<body>
<h1>Namespace for LoST Planned Change extension</h1>
<h2>urn:ietf:params:xml:ns:lost-plannedChange1</h2>
<p>See <a href="http://www.rfc-editor.org/rfc/rfc????.txt">
RFC????</a>.</p>
</body>
</html>
END
11. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC5222] Hardie, T., Newton, A., Schulzrinne, H., and H.
Tschofenig, "LoST: A Location-to-Service Translation
Protocol", RFC 5222, DOI 10.17487/RFC5222, August 2008,
<https://www.rfc-editor.org/info/rfc5222>.
Author's Address
Brian Rosen
470 Conrad Dr
Mars, PA 16046
US
EMail: br@brianrosen.net
Rosen Expires April 26, 2019 [Page 17]
