GeoPriv M. Linsner Internet Draft Cisco Systems Intended status: Standards Track A. Thomson Expires: January 2009 Cisco Systems July 14, 2008 Campus/Building Relative Location for Civic Location Format draft-linsner-geopriv-relativeloc-02.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on January 15, 2009. Copyright Notice Copyright (C) The IETF Trust (2008). Abstract This document defines additional civic address parameters for use in Location Objects [1], [2], and [4]. The format is based on the civic address definition of PIDF-LO. These additional parameters allow expression of a relative location within a building or campus. Linsner & Thomson Expires January 15, 2009 [Page 1] Internet-Draft Civic Relative Location for PIDF-LO July 2008 Conventions used in this document In examples, "C:" and "S:" indicate lines sent by the client and server respectively. 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 [1]. Table of Contents 1. Introduction...................................................2 2. Additions to PIDF-LO...........................................3 3. Additions to DHCP Civic Location Option........................3 4. Relative Location..............................................3 4.1. Examples of the relative location parameters..............5 5. Example Schema.................................................6 6. Security Considerations........................................7 7. IANA Considerations............................................7 7.1. XML Schema Registration...................................7 7.2. CAType Registry Update....................................7 8. Acknowledgments................................................7 9. References.....................................................8 9.1. Normative References......................................8 9.2. Informative References....................................8 Author's Addresses................................................8 Intellectual Property Statement...................................8 Disclaimer of Validity............................................9 1. Introduction Campus wireless LAN technologies are adding capabilities to locate serving hosts via radio frequency measurement technologies. This new capability is able to provide additional and more accurate location information when used inside a building, or on a campus in conjunction with civic addressing. The data produced from these technologies is most useful if expressed as relative position as opposed to expressing as a globally anchored geo location (latitude, longitude). Relative position dictates the expression of a civic anchor point within the confines of the building or campus (a starting point for measurement) hence providing both the relative position and relative location offset from the relative position is provided. The data included within the relative position parameters is supplementary to, not exclusive of, the existing civic location data Linsner & Thomson Expires January 15, 2009 [Page 2] Internet-Draft Civic Relative Location for PIDF-LO July 2008 expressed in PIDF-LO [1], [2] and DHCP Civic Location option [4]. An example of this may be a popular wireless hotspot located at 234 N. Main St. It is reasonable to expect that 234 N. Main St. covers a geographic area that encompasses several hundred square meters. The wireless network architecture for this hotspot could include several wireless infrastructure access points. The supplementary data provided via relative location would enable a more granular location expression. In addition to providing 234 N. Main St., a relative position like "20 feet south and 40 feet east of the main entrance" could be added. It is expected this supplementary civic location data will be used within the confines of the associated civic location and SHOULD not be used to represent locations that are off-campus, or outside the boundary of the expressed civic address. In other words, using the cited example, providing a street address of 234 N. Main St. and then provide this relative location data that result in the location residing at another street address SHOULD not be allowed. Although [1] and [4] currently supports additional elements, like CAtypes 28 (room), 32 (additional code), or 33 (seat), results from the radio frequency measurement technologies are alternatives to these existing elements and in some cases the resultant location can be more accurate. 2. Additions to PIDF-LO PIDF-LO, as updated by [2], includes a full set of parameters used to describe civic locations. The new parameters defined here are additional to the updated set and provide a means to describe a host's civic location with added granularity. 3. Additions to DHCP Civic Location Option The new parameters defined here are additional and will update DHCP Civic Location Option [4] 4. Relative Location Relative location is defined by 2 new parameters, reference point and relative position. Reference point, similar to geodetic datum, defines the anchor point (0,0 point) used for measurement of the relative position parameter. Measurement from the anchor point is provided in 3 dimensions, X, Y and Z. The east-west dimension is labeled X and north-south dimension is labeled Y. A positive Y value is considered north of the reference point, a negative Y value south of the reference point, a positive X value for east of the reference Linsner & Thomson Expires January 15, 2009 [Page 3] Internet-Draft Civic Relative Location for PIDF-LO July 2008 point and a negative X value for west of the reference point. An additional value in this relative position parameter defines the unit of measure (UoM). Lack of expressing a measurement unit defaults the unit value to meters. The fourth, height or altitude parameter (Z) found in normal geodetic systems can be optionally expressed via these new parameters but might be more useful converted to floor values and expressed in via CAtype 27, the FLR or Floor parameter, previously defined for [1] and [4]. If the altitude (Z) parameter is expressed, it is assumed to utilize locally significant ground level (the ground directly below the relative location) as the reference point from which to measure. To provide the most accurate location and due to the uniqueness of earth curvature with respect to perpendicular lines, the east-west measurement SHOULD be calculated/plotted first, followed by the north-south value. For this usage, defining the reference point of local significance is completely subjective, but utilizing intuitively obviously locations, like 'Elevator', 'Exit Door', 'Stairwell', etc. is suggested. Linsner & Thomson Expires January 15, 2009 [Page 4] Internet-Draft Civic Relative Location for PIDF-LO July 2008 New Civic CAtype Description Example Field REFPT 40 Reference Point Elevator RELPOS-X 41 Relative Position X -12 RELPOS-Y 42 Relative Position Y 35 RELPOS-Z 43 Relative Position Z 60 optional RELPOS-UOW 44 Units of measurement for feet relative position Optional, default value meters. Table 1: New Civic CAtypes 4.1. Examples of the relative location parameters A location that is 20 meters west and 31 meters south of elevator-1 elevator-1 -20 -31 A location that is 51 feet north and 23 feet east of the corner office corner_office 23 51 Linsner & Thomson Expires January 15, 2009 [Page 5] Internet-Draft Civic Relative Location for PIDF-LO July 2008 feet 5. Example Schema Linsner & Thomson Expires January 15, 2009 [Page 6] Internet-Draft Civic Relative Location for PIDF-LO July 2008 6. Security Considerations The XML parameters defined in the document are additions to the current PIDF-LO specification. Therefore the parameters defined here are subject to the same security considerations of [1]. 7. IANA Considerations 7.1. XML Schema Registration IANA will update the registered XML schema with additions as shown in section 5. of this document. URI: urn:ietf:params:xml:schema:pidf:geopriv10:civicAddr 7.2. CAType Registry Update IANA will update the civic address type registry established by RFC4776. The additions to the registry are shown in Table 1 of the document. 8. Acknowledgments This document was prepared using 2-Word-v2.0.template.dot. The authors would like to thank Martin Thomson and Carl Reed for their contributions to this draft. Linsner & Thomson Expires January 15, 2009 [Page 7] Internet-Draft Civic Relative Location for PIDF-LO July 2008 9. References 9.1. Normative References [1] Petersen, J., "A Presence-based GEOPRIV Location Object Format", RFC 4119, December 2005. [2] Thomson, M. & Winterbottom, J., "Revised Civic Location Format for Presence Identifier Format Location Object (PIDF-LO)", RFC 5139, February 2008. [3] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [4] Schulzrinne, H., "Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Option for Civic Addresses Configuration Information", RFC4776, November 2006 9.2. Informative References Author's Addresses Marc Linsner Cisco Systems, Inc. Marco Island, Florida, USA Email: mlinsner@cisco.com Allan Thomson Cisco Systems, Inc. San Jose, California, USA Email: althomso@cisco.com Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Linsner & Thomson Expires January 15, 2009 [Page 8] Internet-Draft Civic Relative Location for PIDF-LO July 2008 Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Statement Copyright (C) The IETF Trust (2008). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Martin Thomson and Carl Reed made significant contributions to both the usage and technical aspects of the relative location addition to civic locations. 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