Network Working Group A. Lindem, Ed. Internet-Draft N. Shen Intended status: Standards Track E. Chen Expires: April 21, 2018 Cisco Systems October 18, 2017 OSPF Extensions for Advertising/Signaling Geo Location Information draft-acee-ospf-geo-location-05.txt Abstract This document specifies an OSPF Router Information (RI) TLV to advertise the current Geo Coordinates of the OSPF router. For Point- to-Point (P2P)) and Point-to-Multi-Point (P2MP) networks, the Geo Coordinates can be used to dynamically computing the cost to neighbors. This is useful both from the standpoint of auto- configuration and situations where the OSPF routers are moving. The Geo Coordinates are also useful for other applications such as Traffic Engineering (TE) and network management. 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 http://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 21, 2018. Copyright Notice Copyright (c) 2017 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 (http://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 Lindem, et al. Expires April 21, 2018 [Page 1] Internet-Draft OSPF Geo Location Extensions October 2017 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 1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 2 2. OSPF Geo Coordinates TLV . . . . . . . . . . . . . . . . . . 2 3. Link Advertisement of the OSPF Geo-Coordinates . . . . . . . 4 4. OSPFv2 Router Information (RI) Opaque LSA . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. Privacy Considerations . . . . . . . . . . . . . . . . . . . 5 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 6 8.1. Normative References . . . . . . . . . . . . . . . . . . 6 8.2. Informative References . . . . . . . . . . . . . . . . . 6 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 1. Introduction This document specifies an OSPF Router Information (RI) [OSPF-RI] TLV to advertise the current Geo Coordinates of the OSPF router. For Point-to-Point (P2P)) and Point-to-Multi-Point (P2MP) networks, the Geo Coordinates can be used to dynamically computing the cost to neighbors. This is useful both from the standpoint of auto- configuration and situations where the OSPF routers are moving. The Geo Coordinates are also useful for other applications such as Traffic Engineering (TE)and network management. 1.1. Requirements Notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC-KEYWORDS]. 2. OSPF Geo Coordinates TLV The Geo Coordinates TLV can be used to advertise the current location of an OSPFv2 [OSPF] or OSPFv3 [OSPFV3] router using the OSPF Router Information LSA [OSPF-RI]. The OSPF Router Information LSA can be advertised in both link-scoped and area or AS scoped RI LSAs. The fields specify the location of the OSPF router using the WGS-84 (World Geodetic System) reference coordinate system [WGS84]. The value of the Geo Coordinates TLV consists of the following fields: Lindem, et al. Expires April 21, 2018 [Page 2] Internet-Draft OSPF Geo Location Extensions October 2017 0 1 2 3 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |U|N|E|A|M|R|K| Reserved | Location Uncertainty | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Lat Degrees | Latitude Milliseconds | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Long Degrees | Longitude Milliseconds | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Altitude | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Radius | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | .. Optional Sub-TLVs +-+-+-+-+-+-+-+-+-.... Where: U-bit: If the U-bit is set, it indicates that the "Location Uncertainty" field is specified. If the U-bit is clear, it indicates the "Location Uncertainty" field is unspecified. N-bit: If the N-bit is set, it indicates the Latitude is north relative to the Equator. If the N-bit is clear, it indicates the Latitude is south of the Equator. E-bit: If the E-bit is set, it indicates the Longitude is east of the Prime Meridian. If the E-bit is clear, it indicates the Longitude is west of the Prime Meridian. A-bit: If the A-bit is set, it indicates the "Altitude" field is specified. If the A-bit is clear, it indicates the "Altitude" field is unspecified. M-bit: If the M-bit is set, it indicates the "Altitude" is specified in meters. If the M-bit is clear, it indicates the "Altitude" is in centimeters. R-bit: If the R-bit is set, it indicates the "Radius" field is specified and the encoding is for a circular area. If the R-bit is clear, it indicates the "Radius" field is unspecified and the encoding is for a single point. K-bit: If the K-bit is set, it indicates the "Radius" is specified in kilometers. If the K-bit is clear, it indicates the "Radius" is in meters. Lindem, et al. Expires April 21, 2018 [Page 3] Internet-Draft OSPF Geo Location Extensions October 2017 Reserved: These bits are reserved. They SHOULD be set to 0 when sending protocol packets and MUST be ignored when receiving protocol packets. Location Uncertainty: Unsigned 16-bit integer indicating the number of centimeters of uncertainty for the location. Latitude Degrees: Unsigned 8-bit integer with a range of 0 - 90 degrees north or south of the Equator (northern or southern hemisphere, respectively). Latitude Milliseconds: Unsigned 24-bit integer with a range of 0 - 3,599,999 (i.e., less than 60 minutes). Longitude Degrees: Unsigned 8-bit integer with a range of 0 - 180 degrees east or west of the Prime Meridian. Longitude Milliseconds: Unsigned 24-bit integer with a range of 0 - 3,599,999 (i.e., less than 60 minutes). Altitude: Signed 32-bit integer containing the Height relative to sea level in centimeters or meters. A negative height indicates that the location is below sea level. Radius: Unsigned 16-bit integer containing the radius of a circle centered at the specified coordinates. The radius is specified in meters unless the K-bit is specified indicating specification in kilometers. If the radius is specified, the geo-coordinates specify the entire area of the circle defined by the radius and center point. While the use cases herein do not make use of this field, future use cases may. Optional Sub-TLVs: No additional Sub-TLVs are defined in this document. OSPF Geo Coordinates TLV 3. Link Advertisement of the OSPF Geo-Coordinates When the Geo Coordinates are used for cost computation, the coordinates need to be advertised on the link using the encoding specified in Section 2. For this application, a link-scoped OSPF Router Information (RI) [OSPF-RI] is advertised on each link where geo-location cost computation is utilized. Lindem, et al. Expires April 21, 2018 [Page 4] Internet-Draft OSPF Geo Location Extensions October 2017 When an OSPF router receives the Geo Coordinates TLV in a link-scoped OSPF RI LSA from an adjacent neighbor, it can be used to calculate the physical distance to neighbor. For P2P and P2MP networks, this distance can be used to dynamically compute the cost of the link to that neighbor. The mapping of the distance to advertised cost is not specified in this document. However, all OSPF routers in the domain SHOULD used the same algorithm. Computation of cost based on physical distance can be useful both for autoconfiguration of these networks types and dynamic cost computation when the routers are moving. The Geo location information can be statically provisioned or dynamically acquired from a GPS capable device on the OSPF Router. 4. OSPFv2 Router Information (RI) Opaque LSA The OSPF Geo Coordinates TLV may optionally be advertised in the OSPF Router Information (RI) LSA [OSPF-RI]. It then may be used for applications such as traffic engineering (TE) and network management (e.g., the Find-My-Router application). The details of such applications are beyond the scope of this document. 5. Security Considerations Since the Geo Location coordinates provide the exact location of the OSPF router, disclosure will make the OSPF router more susceptible to physical attacks. In situations where this is a concern (e.g., military applications), confidentiality should be provided either through a secure tunnel (e.g., [IP-ESP]) or protocol encryption [OSPFV3-AUTH]. Additionally, in some situations, the topology of the network is considered proprietary information. With the Geo Location coordinates, the physical topology, as well as the IP topology, can be discerned from the OSPF Router Information (RI) LSA. In these situations, confidentiality should be assured. Security considerations for the base OSPF protocol are covered in [OSPF] and [OSPFV3]. 6. Privacy Considerations If the location of an OSPF router advertising geo location coordinates as described herein can be directly correlated to an individual, individuals, or an organization, the location of that router should be considered sensitive and OSPF RI LSAs containing such geo coordinates should be advertised confidentially as described in Section 5. Additionally, OSPF network management facilities may Lindem, et al. Expires April 21, 2018 [Page 5] Internet-Draft OSPF Geo Location Extensions October 2017 require added authorization to view the contents of OSPF RI LSAs containing geo-Location TLVs. Refer to [PRIVACY] for more information. The Uncertainty and Confidence metrics for geo-location information as described in [GEO-PIDF-LO] are not included in the Geo Coordinates TLV. In a future document, these may be considered for inclusion with additional Geo Location Sub-TLVs dependent on both on requirements and adoption of [GEO-PIDF-LO]. 7. IANA Considerations The document will require the following IANA actions: 1. A Router Information TLV type for the Geo Location TLV will be allocated from the OSPF Router Information (RI) TLVs registry. 8. References 8.1. Normative References [OSPF] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998. [OSPF-RI] Lindem, A., Shen, N., Vasseur, J., Aggarwal, R., and S. Shaffer, "Extensions to OSPF for Advertising Optional Router Capabilities", RFC 7770, January 2016. [OSPFV3] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF for IPv6", RFC 5340, July 2008. [RFC-KEYWORDS] Bradner, S., "Key words for use in RFC's to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 8.2. Informative References [GEO-PIDF-LO] Thomson, M. and J. Winterbottom, "Representation of Uncertainty and Confidence in the Presence Information Data Location Object (PIDF-LO)", RFC 7459, February 2015. [IP-ESP] Kent, S., "IP Encapsulation Security Payload (ESP)", RFC 4303, December 2005. [LISP-GEO] Farinacci, D., "LISP Geo-Coordinate Use-Cases", draft- farinacci-lisp-geo-03 (work in progress), April 2017. Lindem, et al. Expires April 21, 2018 [Page 6] Internet-Draft OSPF Geo Location Extensions October 2017 [OSPFV3-AUTH] Gupta, M. and S. Melam, "Authentication/Confidentiality for OSPFv3", RFC 4552, June 2006. [PRIVACY] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J., Morris, J., Hansen, M., and R. Smith, "Privacy Considerations", RFC 6973, July 2013. [WGS84] National Imagery and Mapping Agency, "Department of Defense World Geodetic System 1984, Third Edition", NIMA TR83500.2, January 2000. Appendix A. Acknowledgments The RFC text was produced using Marshall Rose's xml2rfc tool. The encoding of the Geo location is adapted from "LISP Geo- Coordinates Use-Cases" [LISP-GEO]. We would like to thank the author, Dino Farinacci, for subsequent discussions. Thanks to Yi Yang for review and discussions of the Geo Coordinate encoding. The use-case for using OSPF to advertise the geo-location in OSPF was first mentioned in an OSPF operator-defined TLV draft by Uma Chunduri, Xiaohu Xu, Luis M. Contreras, Mohamed Boucadair, and Luay Jalil. Authors' Addresses Acee Lindem (editor) Cisco Systems 301 Midenhall Way Cary, NC 27513 USA Email: acee@cisco.com Naiming Shen Cisco Systems 821 Alder Drive Milpitas, CA 95935 USA Email: naiming@cisco.com Lindem, et al. Expires April 21, 2018 [Page 7] Internet-Draft OSPF Geo Location Extensions October 2017 Enke Chen Cisco Systems 821 Alder Drive Milpitas, CA 95935 USA Email: enkechen@cisco.com Lindem, et al. Expires April 21, 2018 [Page 8]