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2 GEOPRIV R. Barnes
3 Internet-Draft BBN Technologies
4 Intended status: Informational M. Thomson
5 Expires: December 22, 2011 J. Winterbottom
6 Andrew Corporation
7 H. Tschofenig
8 Nokia Siemens Networks
9 June 20, 2011
11 Location Configuration Extensions for Policy Management
12 draft-ietf-geopriv-policy-uri-01.txt
14 Abstract
16 Current location configuration protocols are capable of provisioning
17 an Internet host with a location URI that refers to the host's
18 location. These protocols lack a mechanism for the target host to
19 inspect or set the privacy rules that are applied to the URIs they
20 distribute. This document extends the current location configuration
21 protocols to provide hosts with a reference to the rules that are
22 applied to a URI, so that the host can view or set these rules.
24 Status of this Memo
26 This Internet-Draft is submitted in full conformance with the
27 provisions of BCP 78 and BCP 79.
29 Internet-Drafts are working documents of the Internet Engineering
30 Task Force (IETF). Note that other groups may also distribute
31 working documents as Internet-Drafts. The list of current Internet-
32 Drafts is at http://datatracker.ietf.org/drafts/current/.
34 Internet-Drafts are draft documents valid for a maximum of six months
35 and may be updated, replaced, or obsoleted by other documents at any
36 time. It is inappropriate to use Internet-Drafts as reference
37 material or to cite them other than as "work in progress."
39 This Internet-Draft will expire on December 22, 2011.
41 Copyright Notice
43 Copyright (c) 2011 IETF Trust and the persons identified as the
44 document authors. All rights reserved.
46 This document is subject to BCP 78 and the IETF Trust's Legal
47 Provisions Relating to IETF Documents
48 (http://trustee.ietf.org/license-info) in effect on the date of
49 publication of this document. Please review these documents
50 carefully, as they describe your rights and restrictions with respect
51 to this document. Code Components extracted from this document must
52 include Simplified BSD License text as described in Section 4.e of
53 the Trust Legal Provisions and are provided without warranty as
54 described in the Simplified BSD License.
56 Table of Contents
58 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
59 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 4
60 3. Policy URIs . . . . . . . . . . . . . . . . . . . . . . . . . 4
61 3.1. Policy URI Usage . . . . . . . . . . . . . . . . . . . . . 5
62 3.2. Policy URI Allocation . . . . . . . . . . . . . . . . . . 6
63 4. Location Configuration Extensions . . . . . . . . . . . . . . 7
64 4.1. HELD . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
65 4.2. DHCP . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
66 4.3. Client Processing . . . . . . . . . . . . . . . . . . . . 8
67 5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
68 5.1. HELD . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
69 5.2. DHCP . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
70 5.3. Basic Access Control Policy . . . . . . . . . . . . . . . 10
71 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 11
72 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
73 7.1. URN Sub-Namespace Registration for
74 urn:ietf:params:xml:ns:geopriv:held:policy . . . . . . . . 12
75 7.2. XML Schema Registration . . . . . . . . . . . . . . . . . 12
76 7.3. DHCP LuriType Registration . . . . . . . . . . . . . . . . 13
77 8. Security Considerations . . . . . . . . . . . . . . . . . . . 13
78 8.1. Integrity and Confidentiality for Authorization Policy
79 Data . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
80 8.2. Access Control for Authorization Policy . . . . . . . . . 14
81 8.3. Location URI Allocation . . . . . . . . . . . . . . . . . 14
82 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
83 9.1. Normative References . . . . . . . . . . . . . . . . . . . 15
84 9.2. Informative References . . . . . . . . . . . . . . . . . . 15
85 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
87 1. Introduction
89 A critical step in enabling Internet hosts to access location-based
90 services is to provision those hosts with information about their own
91 location. This is accomplished via a Location Configuration Protocol
92 (LCP) [RFC5687], which allows a location provider (e.g., a local
93 access network) to inform a host about its location.
95 There are two basic patterns for location configuration, namely
96 configuration "by value" and "by reference" [RFC5808]. Configuration
97 by value provisions a host directly with its location, by providing
98 it location information that is directly usable (e.g., coordinates or
99 a civic address). Configuration by reference provides a host with a
100 URI that references the host's location, i.e., one that can be
101 dereferenced to obtain the location (by value) of the host.
103 In some cases, location by reference offers a few benefits over
104 location by value. From a privacy perspective, the required
105 dereference transaction provides a policy enforcement point, so that
106 the opaque URI itself can be safely conveyed over untrusted media
107 (e.g., SIP through untrusted proxies [RFC5606]). If the target host
108 is mobile, an application provider can use a single reference to
109 obtain the location of the host multiple times, saving bandwidth to
110 the host. For some configuration protocols, the location object
111 referenced by a location URI provides a much more expressive syntax
112 for location values than the configuration protocol itself (e.g.,
113 DHCP geodetic location [I-D.ietf-geopriv-rfc3825bis] versus GML in a
114 PIDF-LO [RFC4119]).
116 From a privacy perspective, however, current LCPs are limited in
117 their flexibility, in that they do not provide hosts (the clients in
118 an LCP) with a way to inform the Location Server with policy for how
119 his location information should be handled. This document addresses
120 this gap by defining a simple mechanism for referring to and
121 manipulating policy, and by extending current LCPs to carry policy
122 references. Using the mechanisms defined in this document, an LCP
123 server (acting for the Location Server) can inform a host as to which
124 policy document controls a given location resource, and the host (in
125 its Rule Maker role) can inspect this document and modify it as
126 necessary.
128 In the following figure, adapted from RFC 5808, this document extends
129 the Location Configuration Protocols (1) and defines a simple
130 protocol for policy exchange (4).
132 +---------+---------+ Location +-----------+
133 | | | Dereference | Location |
134 | LIS/LS +---------------+ Recipient |
135 | | | Protocol | |
136 +----+----+----+----+ (3) +-----+-----+
137 | | |
138 | | |
139 Policy| |Location |Location
140 Exchange| |Configuration |Conveyance
141 (4)| |Protocol |Protocol
142 | |(1) |(2)
143 | | |
144 +------+----+----+----+ |
145 | Rule | Target/ | |
146 | Maker | Host +---------------------+
147 | | |
148 +-----------+---------+
150 The remainder of this document is structured as follows: After
151 introducing a few relevant terms, we define policy URIs as a channel
152 for referencing, inspecting, and updating policy documents. We then
153 define extensions to the HELD protocol and the DHCP option for
154 location by reference to allow these protocols to carry policy URIs.
155 Examples are given that demonstrate how policy URIs are carried in
156 these protocols and how they can be used by clients.
158 2. Definitions
160 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
161 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
162 document are to be interpreted as described in RFC 2119 [RFC2119].
164 3. Policy URIs
166 A policy URI is an HTTP [RFC2616] or HTTPS [RFC2818]URI that
167 identifies a policy resource that contains the authorization policy
168 for a linked location resource. Access to the location resource is
169 governed by the contents of the authorization policy.
171 A policy URI identifies an HTTP resource that a Rule Maker can use to
172 inspect and install policy documents that tell a Location Server how
173 it should protect the associated location resource. A policy URI
174 always identifies a resource that can be represented as a common-
175 policy document [RFC4745] (possibly including some extensions; e.g.,
176 for geolocation policy [I-D.ietf-geopriv-policy]).
178 Note: RFC 3693 [RFC3693] identified the Rule Holder role as the one
179 that stores policy information. In this document, the Location
180 Server is also a Rule Holder.
182 3.1. Policy URI Usage
184 A Location Server that is the authority for policy URIs MUST support
185 GET, PUT, and DELETE requests to these URIs, in order to allow
186 clients to inspect, replace, and delete policy documents. Clients
187 support the three request methods as they desire to perform these
188 operations.
190 Knowledge of the policy URI can be considered adequate evidence of
191 authorization. A Location Server SHOULD allow all requests, but it
192 MAY deny certain requests based on local policy. For instance, a
193 Location Server might allow clients to inspect policy (GET), but not
194 to update it (PUT).
196 A GET request to a policy URI is a request for the referenced policy
197 information. If the request is authorized, then the Location Server
198 sends an HTTP 200 response containing the complete policy identified
199 by the URI.
201 A PUT request to a policy URI is a request to replace the current
202 policy. The entity-body of a PUT request includes a complete policy
203 document. When a Location Server receives a PUT request, it MUST
204 validate the policy document included in the body of the request. If
205 the request is valid and authorized, then the Location Server
206 replaces the current policy with the policy provided in the request.
208 A DELETE request to a policy URI is a request to delete the
209 referenced policy document. If the request is authorized, then the
210 Location Server MUST delete the policy referenced by the URI and
211 disallow access to the location URIs it governs until a new policy
212 document has been put in place via a PUT request.
214 A policy URI is only valid while the corresponding location URI set
215 is valid. A location server MUST NOT respond to any requests to a
216 policy URIs once the corresponding location URI set has expired.
217 This expiry time is specified by the 'expires' attribute in the HELD
218 locationResponse or the 'Valid-For' LuriType in DHCP.
220 A location URI can thus become invalid in three ways: By the
221 expiration of a validity interval in policy, by the removal of a
222 policy document with a DELETE request, or by the expiry of the
223 LCP-specified validity interval. The former two are temporary,
224 since the policy URI can be used to update the policy. The latter
225 one is permanent, since the expiry causes the policy URI to be
226 invalidated as well.
228 The Location Server MUST support policy documents in the common-
229 policy format [RFC4745], as identified by the MIME media type of
230 "application/auth-policy+xml". The common-policy format MUST be
231 provided as the default format in response to GET requests that do
232 not include specific "Accept" headers, but content negotiation MAY be
233 used to allow for other formats.
235 This usage of HTTP is generally compatible with the use of XCAP
236 [RFC4825] or WebDAV [RFC4918] to manage policy documents, but this
237 document does not define or require the use of these protocols.
239 3.2. Policy URI Allocation
241 A Location Server creates a policy URI for a specific location
242 resource at the time that the location resource is created; that is,
243 a policy URI is created at the same time as the location URI that it
244 controls. The URI of the policy resource MUST be different to the
245 location URI.
247 A policy URI is provided in response to location configuration
248 requests. A policy URI MUST NOT be provided to an entity that is not
249 authorized to view or set policy. This document does not describe
250 how policy might be provided to entities other than for location
251 configuration. In responses to dereferencing requests
252 [I-D.ietf-geopriv-deref-protocol] or requests from third parties
253 [RFC6155].
255 Each location URI has either one policy URI or no policy URI. The
256 initial policy that is referenced by a policy URI MUST be identical
257 to the policy that would be applied in the absence of a policy URI.
258 A client that does not support policy URIs can continue to use the
259 location URI as they would have if no policy URI were provided.
261 For DHCP and HELD, the client assumes that the default policy
262 grants any requester access to location information, as long as
263 the request possesses the location URI. To ensure that the
264 authorization policy is less permissive, a client updates the
265 policy prior to distributing the location URI.
267 A Location Server chooses whether or not to provide a policy URI
268 based on local policy. A HELD-specific extension also allows a
269 requester to specifically ask for a policy URI.
271 A policy URI is effectively a shared secret between Location Server
272 and its clients. Knowledge of a policy URI is all that is required
273 to perform any operations allowed on the policy. Thus, a policy URI
274 should be constructed so that it is hard to predict and
275 confidentiality-protected when transmitted (see Section 8). To avoid
276 re-using these shared secrets, the Location Server MUST generate a
277 new policy URI whenever it generates a new location URI set.
279 4. Location Configuration Extensions
281 Location configuration protocols can provision hosts with location
282 URIs that refer to the host's location. If the target host is to
283 control policy on these URIs, it needs a way to access the policy
284 that the Location Server uses to guide how it serves location URIs.
285 This section defines extensions to LCPs to carry policy URIs that the
286 target can use to control access to location resources.
288 4.1. HELD
290 The HELD protocol [RFC5985] defines a "locationUriSet" element, which
291 contain a set of one or more location URIs that reference the same
292 resource and share a common access control policy. The schema in
293 Figure 1 defines two extension elements for HELD: an empty
294 "requestPolicyUri" element that is added to a location request to
295 indicate that a Device desires that a policy URI be allocated; and a
296 "policyUri" element that is included in the location response.
298
299
305
306
307
309
311
313 Figure 1
315 The URI carried in a "policyUri" element refers to the common access
316 control policy for location URIs in the location response. The URI
317 MUST be a policy URI as described in Section 3. A policy URI MUST
318 use the "http:" or "http:" scheme, and the Location Server MUST
319 support the specified operations on the URI.
321 A HELD request MAY contain an explicit request for a policy URI. The
322 presence of the "requestPolicyUri" element in a location request
323 indicates that a policy URI is desired.
325 4.2. DHCP
327 The DHCP location by reference option
328 [I-D.ietf-geopriv-dhcp-lbyr-uri-option] provides location URIs in
329 sub-options called LuriElements. This document defines a new
330 LuriElement type for policy URIs.
332 LuriType=TBD Policy-URI - This is a policy URI that refers to the
333 access control policy for the location URIs.
335 [NOTE TO IANA/RFC-EDITOR: Please replace TBD above with the assigned
336 LuriType value and remove this note]
338 A Policy-URI LuriElement uses a UTF-8 character encoding.
340 A Policy-URI LuriElement identifies the policy resource for all
341 location URIs included in the location URI option. The URI MUST be a
342 policy URI as described in Section 3: It MUST use either the "http:"
343 or "https:" scheme, and the Location Server MUST support the
344 specified operations on the URI.
346 4.3. Client Processing
348 It is possible that this document will be updated to allow the use of
349 policy URIs that use protocols other than the HTTP-based protocol
350 described above. To ensure that they fail safely when presented with
351 such a URI, clients implementing this specification MUST verify that
352 a policy URI received from either HELD or DHCP uses either the
353 "http:" or "https:" scheme. If the URI does not match those schemes,
354 then the client MUST discard the URI and behave as if no policy URI
355 was provided.
357 5. Examples
359 In this section, we provide some brief illustrations of how policy
360 URIs are delivered to target hosts and used by those hosts to manage
361 policy.
363 5.1. HELD
365 A HELD request that explicitly requests the creation of a policy URI
366 has the following form:
368
369 locationURI
370
372
374 A HELD response providing a single "locationUriSet", containing two
375 URIs under a common policy, would have the following form:
377
378
379
380 https://ls.example.com:9768/357yc6s64ceyoiuy5ax3o
381
382
383 sip:9769+357yc6s64ceyoiuy5ax3o@ls.example.com:
384
385
386
387 https://ls.example.com:9768/policy/357lp6f64prlbvhl5nk3b
388
389
391 5.2. DHCP
393 A DHCP option providing one of the location URIs and the
394 corresponding policy URI from the previous example would have the
395 following form:
397 0 1 2 3
398 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
399 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
400 | option-code | 110 |
401 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
402 | 1 | 0 | 1 | 49 | 'h' |
403 +---------------+---------------+---------------+---------------|
404 | 't' | 't' | 'p' | 's' |
405 +---------------+---------------+---------------+---------------|
406 | ':' | '/' | '/' | 'l' |
407 +---------------+---------------+---------------+---------------|
408 | 's' | '.' | ... |
409 +---------------+---------------+---------------+---------------|
410 | TBD | 56 | 'h' 't' |
411 +---------------+---------------+---------------+---------------|
412 | 't' | 'p' | 's' | ':' |
413 +---------------+---------------+---------------+---------------|
414 | '/' | '/' | ... |
415 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
417 [NOTE TO IANA/RFC-EDITOR: Please replace TBD above with the assigned
418 LuriType value and remove this note]
420 5.3. Basic Access Control Policy
422 Consider a client that gets the policy URI
423 , as in the
424 above LCP example. The first thing this allows the client to do is
425 inspect the default policy that the LS has assigned to this URI:
427 GET /policy/357lp6f64prlbvhl5nk3b HTTP/1.1
428 Host: ls.example.com:9768
430 HTTP/1.1 200 OK
431 Content-type: application/auth-policy+xml
432 Content-length: 388
434
435
437
438
439
440 2011-01-01T13:00:00.0Z
441
442
443
444
445
446
447 false
448
449 0
450
451
452
454 This policy allows any requester to obtain location information, as
455 long as they know the location URI. If the user disagrees with this
456 policy, and prefers for example, to only provide location to one
457 friend, at a city level of granularity, then the client can install
458 this policy on the Location Server:
460 PUT /policy/357lp6f64prlbvhl5nk3b HTTP/1.1
461 Host: ls.example.com:9768
462 Content-type: application/auth-policy+xml
463 Content-length: 462
465
466
467
468
469
470
471
472
473 2011-01-01T13:00:00.0Z
474
475
476
477
478
480 city
481
482
483
484
486 HTTP/1.1 200 OK
488 Finally, after using the URI for a period, the user wishes to
489 permanently invalidate the URI.
491 DELETE /policy/357lp6f64prlbvhl5nk3b HTTP/1.1
492 Host: ls.example.com:9768
494 HTTP/1.1 200 OK
496 6. Acknowledgements
498 Thanks to Mary Barnes, Alissa Cooper, and Hannes Tschofenig for
499 providing critical commentary and input on the ideas described in
500 this document.
502 7. IANA Considerations
504 This document requires several IANA registrations, detailed below.
506 7.1. URN Sub-Namespace Registration for
507 urn:ietf:params:xml:ns:geopriv:held:policy
509 This section registers a new XML namespace,
510 "urn:ietf:params:xml:ns:geopriv:held:policy", per the guidelines in
511 [RFC3688].
513 URI: urn:ietf:params:xml:ns:geopriv:held:policy
515 Registrant Contact: IETF, GEOPRIV working group,
516 (geopriv@ietf.org), Richard Barnes (rbarnes@bbn.com).
518 XML:
520 BEGIN
521
522
524
525
526 HELD Policy URI Extension
527
528
529 Namespace for HELD Policy URI Extension
530 urn:ietf:params:xml:ns:geopriv:held:policy
531 [NOTE TO IANA/RFC-EDITOR: Please replace XXXX
532 with the RFC number for this specification.]
533 See RFCXXXX
534
535
536 END
538 7.2. XML Schema Registration
540 This section registers an XML schema as per the guidelines in
541 [RFC3688].
543 URI: urn:ietf:params:xml:schema:geopriv:held:policy
545 Registrant Contact: IETF, GEOPRIV working group (geopriv@ietf.org),
546 Richard Barnes (rbarnes@bbn.com)
548 Schema: The XML for this schema can be found in Section Section 4.1.
550 7.3. DHCP LuriType Registration
552 IANA is requested to add a value to the LuriTypes registry, as
553 follows:
555 +------------+----------------------------------------+-----------+
556 | LuriType | Name | Reference |
557 +------------+----------------------------------------+-----------+
558 | TBD* | Policy-URI | RFC XXXX**|
559 +------------+----------------------------------------+-----------+
561 * TBD is to be replaced with the assigned value
562 ** RFC XXXX is to be replaced with this document's RFC number.
564 8. Security Considerations
566 There are two main classes of risks associated with access control
567 policy management: The risk of unauthorized disclosure of the
568 protected resource via manipulation of the policy management process,
569 and the risk of disclosure of policy information itself.
571 Protecting the policy management process from manipulation entails
572 two primary requirements: First, the policy URI has to be faithfully
573 and confidentially transmitted to the client, and second, the policy
574 document has to be faithfully and confidentially transmitted to the
575 Location Server. The mechanism also needs to ensure that only
576 authorized entities are able to acquire or alter policy.
578 8.1. Integrity and Confidentiality for Authorization Policy Data
580 Each LCP ensures integrity and confidentiality through different
581 means (see [RFC5985] and [I-D.ietf-geopriv-dhcp-lbyr-uri-option]).
582 These measures ensure that a policy URI is conveyed to the client
583 without modification or interception.
585 To protect the integrity and confidentiality of policy data during
586 management, the Location Server SHOULD provide policy URIs with the
587 "https:" scheme and require the use of HTTP over TLS [RFC2818]. The
588 cipher suites required by TLS [RFC5246] provide both integrity
589 protection and confidentiality. If other means of protection are
590 available, an "http:" URI MAY be used.
592 8.2. Access Control for Authorization Policy
594 Access control for the policy resource is based on knowledge of its
595 URI. The URI of a policy resource operates under the same
596 constraints as a possession model location URI [RFC5808] and is
597 subject to the same constraints:
599 o Knowledge of a policy URI MUST be restricted to authorized Rule
600 Makers. Confidentiality is required for its conveyance in the
601 location configuration protocol, and in the requests that are used
602 to inspect, change or delete the policy resource.
604 o The Location Server MUST ensure that the URI cannot be easily
605 predicted. The policy URI MUST NOT be derived solely from
606 information that might be public, including the Target identity or
607 any location URI. The addition of random entropy increases the
608 difficulty of guessing a policy URI.
610 8.3. Location URI Allocation
612 A policy URI enables the authorization by access control lists model
613 [RFC5808] for associated location URIs. Under this model, it might
614 be possible to more widely distribute a location URI, relying on the
615 authorization policy to constrain access to location information.
617 To allow for wider distribution, authorization by access control
618 lists places additional constraints on the construction of location
619 URIs.
621 If multiple Targets share a location URI, an unauthorized location
622 recipient that acquires location URIs for the Targets can determine
623 that the Targets are at the same location by comparing location URIs.
624 With shared policy URIs, Targets are able to see and modify
625 authorization policy for other Targets.
627 To allow for the creation of Target-specific authorization policies
628 that are adequately privacy-protected, each location URI and policy
629 URI that is issued to a different Target MUST be different from other
630 location URIs and policy URIs. That is, two clients MUST NOT receive
631 the same location URI or the same policy URI.
633 In some deployments, it is not always apparent to a LCP server that
634 two clients are different. In particular, where a middlebox
635 [RFC3234] exists two or more clients might appear as a single client.
636 An example of a deployment scenario of this nature is described in
637 [RFC5687]. An LCP server MUST create a different location URI and
638 policy URI for every request, unless the requests can be reliably
639 identified as being from the same client.
641 9. References
643 9.1. Normative References
645 [I-D.ietf-geopriv-dhcp-lbyr-uri-option]
646 Polk, J., "Dynamic Host Configuration Protocol (DHCP) IPv4
647 and IPv6 Option for a Location Uniform Resource Identifier
648 (URI)", draft-ietf-geopriv-dhcp-lbyr-uri-option-11 (work
649 in progress), February 2011.
651 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
652 Requirement Levels", BCP 14, RFC 2119, March 1997.
654 [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
655 Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
656 Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
658 [RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
660 [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
661 January 2004.
663 [RFC4745] Schulzrinne, H., Tschofenig, H., Morris, J., Cuellar, J.,
664 Polk, J., and J. Rosenberg, "Common Policy: A Document
665 Format for Expressing Privacy Preferences", RFC 4745,
666 February 2007.
668 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
669 (TLS) Protocol Version 1.2", RFC 5246, August 2008.
671 [RFC5985] Barnes, M., "HTTP-Enabled Location Delivery (HELD)",
672 RFC 5985, September 2010.
674 9.2. Informative References
676 [I-D.ietf-geopriv-deref-protocol]
677 Winterbottom, J., Tschofenig, H., Schulzrinne, H.,
678 Thomson, M., and M. Dawson, "A Location Dereferencing
679 Protocol Using HELD", draft-ietf-geopriv-deref-protocol-02
680 (work in progress), December 2010.
682 [I-D.ietf-geopriv-policy]
683 Schulzrinne, H., Tschofenig, H., Morris, J., Cuellar, J.,
684 and J. Polk, "Geolocation Policy: A Document Format for
685 Expressing Privacy Preferences for Location Information",
686 draft-ietf-geopriv-policy-23 (work in progress),
687 March 2011.
689 [I-D.ietf-geopriv-rfc3825bis]
690 Polk, J., Linsner, M., Thomson, M., and B. Aboba, "Dynamic
691 Host Configuration Protocol Options for Coordinate-based
692 Location Configuration Information",
693 draft-ietf-geopriv-rfc3825bis-17 (work in progress),
694 February 2011.
696 [RFC3234] Carpenter, B. and S. Brim, "Middleboxes: Taxonomy and
697 Issues", RFC 3234, February 2002.
699 [RFC3693] Cuellar, J., Morris, J., Mulligan, D., Peterson, J., and
700 J. Polk, "Geopriv Requirements", RFC 3693, February 2004.
702 [RFC4119] Peterson, J., "A Presence-based GEOPRIV Location Object
703 Format", RFC 4119, December 2005.
705 [RFC4825] Rosenberg, J., "The Extensible Markup Language (XML)
706 Configuration Access Protocol (XCAP)", RFC 4825, May 2007.
708 [RFC4918] Dusseault, L., "HTTP Extensions for Web Distributed
709 Authoring and Versioning (WebDAV)", RFC 4918, June 2007.
711 [RFC5606] Peterson, J., Hardie, T., and J. Morris, "Implications of
712 'retransmission-allowed' for SIP Location Conveyance",
713 RFC 5606, August 2009.
715 [RFC5687] Tschofenig, H. and H. Schulzrinne, "GEOPRIV Layer 7
716 Location Configuration Protocol: Problem Statement and
717 Requirements", RFC 5687, March 2010.
719 [RFC5808] Marshall, R., "Requirements for a Location-by-Reference
720 Mechanism", RFC 5808, May 2010.
722 [RFC6155] Winterbottom, J., Thomson, M., Tschofenig, H., and R.
723 Barnes, "Use of Device Identity in HTTP-Enabled Location
724 Delivery (HELD)", RFC 6155, March 2011.
726 Authors' Addresses
728 Richard Barnes
729 BBN Technologies
730 9861 Broken Land Parkway
731 Columbia, MD 21046
732 US
734 Phone: +1 410 290 6169
735 Email: rbarnes@bbn.com
737 Martin Thomson
738 Andrew Corporation
739 Andrew Building (39)
740 Wollongong University Campus
741 Northfields Avenue
742 Wollongong, NSW 2522
743 AU
745 Phone: +61 2 4221 2915
746 Email: martin.thomson@andrew.com
748 James Winterbottom
749 Andrew Corporation
750 Andrew Building (39)
751 Wollongong University Campus
752 Northfields Avenue
753 Wollongong, NSW 2522
754 AU
756 Phone: +61 242 212938
757 Email: james.winterbottom@andrew.com
759 Hannes Tschofenig
760 Nokia Siemens Networks
761 Linnoitustie 6
762 Espoo 02600
763 Finland
765 Phone: +358 (50) 4871445
766 Email: Hannes.Tschofenig@gmx.net
767 URI: http://www.tschofenig.priv.at