NETEXT WG R. Pazhyannur Internet-Draft S. Speicher Intended status: Standards Track S. Gundavelli Expires: August 18, 2014 Cisco J. Korhonen Broadcom February 14, 2014 Civic Location ANI Suboption for PMIPv6 draft-pazhyannur-netext-civic-location-ani-subopt-01.txt Abstract This specification defines extensions to Access Network Identifier mobility option for carrying the Civic Location information and MAG Group Identifer from the mobile access gateway to the local mobility anchor. This specificaton also defines a new ANI update timer sub- option that enables a MAG to communicate when the MAG will update the ANI information. This helps the LMA determine the freshness of the ANI options. 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 August 18, 2014. Copyright Notice Copyright (c) 2014 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 Pazhyannur, et al. Expires August 18, 2014 [Page 1] Internet-Draft Extensions to ANI February 2014 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 . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4 2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 3. Civic-Location Sub-Option . . . . . . . . . . . . . . . . . . 4 4. MAG Group-Id Sub-Option . . . . . . . . . . . . . . . . . . . 5 5. ANI Update-Timer Sub-Option . . . . . . . . . . . . . . . . . 6 6. Usage Example . . . . . . . . . . . . . . . . . . . . . . . . 7 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 8. Security Considerations . . . . . . . . . . . . . . . . . . . 9 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10 10.1. Normative References . . . . . . . . . . . . . . . . . . . 10 10.2. Informative References . . . . . . . . . . . . . . . . . . 10 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 10 Pazhyannur, et al. Expires August 18, 2014 [Page 2] Internet-Draft Extensions to ANI February 2014 1. Introduction In many deployments, the LMA needs to be aware of various identifiers of client's access network to ensure appropriate policies are implemented. For example, the LMA may provide access network identifiers to location based applications. [RFC6757] defined new mobility options to enable a MAG to provide Access Network Information (ANI). In Wi-Fi systems the ANI mobility option may carry the identifier of the Access Point (for instance the BSSID, AP- Name, or the geo-spatial coordinates of the Acess Point). When a client associates with an Access Point, the MAG (corresponding to the AP) may send the ANI (like SSID, BSSID, Geo-location) to the LMA. In many deployments (especially indoor AP deployments), it is difficult to provide Geo-spatial coordinates of APs. However, for many location based applications the civic location is sufficient. To provide civic location information, this document defines a new ANI sub-option within the ANI mobilty option defined in [RFC6757]. [RFC4776] provides further motivations on usage of civic information in providing human-usable information, particularly within buildings. We also address an aspect related to ANI, frequency of ANI Update. In other words, how often does the MAG update the ANI. To understand this better, it is instructive to look at this closely in two Wi-Fi deployment scenarios: MAG is co-located with the Access Point: In this scenario, whenever the Wi-Fi client hands over from a source Access Point to a target Access Point there is new Proxy Binding Update (PBU) sent by the MAG on the target AP. If the PBU contains ANI information related to BSSID, or Geo-Lcation then those will correspondng to that of the target Access Point. As a result, the LMA has the latest ANI. MAG is not co-located with Access Point: An example of such a deployment is when the MAG may be co-located with a Wireless LAN Controller (WLC) also known as an Access Controller (as defined in [RFC5415] and [RFC5416]) or it may be co-located with an Access Router. Additionally in these deployments, the Mobile Node mobility between Access Points may be handled by acesss network (layer 2) specific methods and may not require any PMIPv6 signaling. Specifically, there may be no need for MAG to trigger a PBU when a client hands over from one AP another AP. As a result, in these cases it is possible (depending on which ANI sub options were sent by the MAG), the LMA may have "stale" acess network identifers. For example, the LMA may contain the BSSID or Geo-Location of a previously associated AP and not the currently associated AP. If the network deployment and applications that use ANI require the Pazhyannur, et al. Expires August 18, 2014 [Page 3] Internet-Draft Extensions to ANI February 2014 LMA to have the current ANI, then one way of solving this problem is to require the MAG to send a fresh PBU (with updated ANI) whenever it is aware of an ANI change. This is an acceptable solution when the MAG is aggregating a small number (say between 1 and 4) APs. Consider a Wi-Fi deployment in stadium or in large exposition center or a large enterprise. The number of APs in such venues could be multiple hundred APs. This combined with a large number of mobility events may create a large number of ANI updates (sent in PBUs). In this specification, we propose a way to mechanism to specify the ANI update interval based on the deployment needs as well as the capability of the MAG and LMA. This specification enables extensions to Access Network Identifier mobility option for carrying Location information of the mobile node from the mobile access gateway to the local mobility anchor. This documents defines a new ANI sub-option that enables a MAG to communicate how often the MAG will update the ANI information. This helps the LMA determine whether the ANI informaiton is fresh or stale. 2. Conventions and Terminology 2.1. Conventions 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 [RFC2119]. 2.2. Terminology All the mobility related terms used in this document are to be interpreted as defined in [RFC5213] and [RFC5844]. 3. Civic-Location Sub-Option The Civic-Location is a mobility sub-option carried in the Access Network Identifier option defined in [RFC6757]. This sub-option carries the Civic Location information of the mobile node as known to the MAG. The format of this option is defined below. Pazhyannur, et al. Expires August 18, 2014 [Page 4] Internet-Draft Extensions to ANI February 2014 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ANI Type=IANA | ANI Length | Civic Location (PIDF Format) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Civic Location (PIDF Format) continued ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Network-Identifier Sub-option ANI Type: ANI Length: Total length of this sub option in octets, excluding the ANI Type and ANI length fields. Civic Location: This format is as specified in the Presence Information Data Format Location Object [RFC5139] with the additional constraint that the length shall not exceed 255 bytes. System architectures may choose to identify the exact PIDF XML elements to be carried in the PIDF object. 4. MAG Group-Id Sub-Option In many deployments, MAGs may be co-located with APs. In such cases, APs may be clustered in a "group". There is a common policy (for QoS, charging, etc) for all MNs connected to the same group. Further, in some cases there is a common policy (for QoS, DPI, etc) between MAGs and LMA in the same group. The group identifier may also serve a proxy for coarse location identification for MNs connected to the group of MAGs. These considerations motivate introduction of a group identifier to a MAG. The MAG Group Identifier is a mobility sub-option carried in the Access Network Identifier option defined in [RFC6757]. The MAG Group Identifier identifies the group affiliation of the mobile access gateway within that Proxy Mobile IPv6 domain. When the MAG is configured with a group identifier, the MAG may send its group-id in the PBU. The usage of the group identifier by the LMA is left to implementation. The format of this option is defined below. Pazhyannur, et al. Expires August 18, 2014 [Page 5] Internet-Draft Extensions to ANI February 2014 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ANI Type=IANA | ANI Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Group Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: MAG Group-Identifier Sub-option ANI Type: ANI Length: Total length of this sub option in octets, excluding the ANI Type and ANI length fields. The value is always 6. Reserved: MUST be set to zero when sending and ignored when received. Group Identifier: 5. ANI Update-Timer Sub-Option The ANI Update Timer is a mobility sub-option carried in the ANI option defined in [RFC6757]. The MAG sends a PBU with an updated value of ANI mobility options when the update-timer expires. Specifically, if the update-timer expires and the ANI values are identical to the last transmitted ANI values, then a PBU shall not be transmitted. When the Update-Timer Sub option is carried in a PBU, it is considered as a proposed value for the update-timer. When the Update-Timer sub option is carried in a PBA, then it is considered as an accepted value for the update-timer. If the MAG does not receive a update-timer sub option in PBA (in response to sending the sub- option in the PBU), then it the MAG behavior with respect to updating the ANI values is left to implementation choices. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ANI Type=IANA | ANI Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Update-Timer | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Pazhyannur, et al. Expires August 18, 2014 [Page 6] Internet-Draft Extensions to ANI February 2014 Figure 3: Network-Identifier Sub-option ANI Type: ANI Length: Total length of this sub option in octets, excluding the ANI Type and ANI length fields is always 6. Reserved: MUST be set to zero when sending and ignored when received. Update-Timer: Update-Timer is a 16 bit unsigned integer. It indicates the time in seconds before the MAG sends an update value of ANI mobility options. A value of 0 indicates that the MAG will send an updated ANI mobility option as soon as it discovers a change in ANI values. 6. Usage Example Consider a case where the MAG is not co-located with an AP. o MN Attaches to Wi-Fi Network o MAG registers with the LMA and provides an Update-Timer ANI sub option. The LMA responds with a value of Update-Timer in the PBA. o Application request LMA for ANI Information o if ANI information is current (for example, the MAG had sent the Update-Timer value of 0) then LMA provides ANI information o if ANI is not current, LMA sends Update Notification with ANI- Update-Requied Notiiication reason o MAG sends a re-registration with updated ANI sub options Pazhyannur, et al. Expires August 18, 2014 [Page 7] Internet-Draft Extensions to ANI February 2014 +--+ +--------+ +------+ +------+ |MN| |AP/WLC | | LMA | |App | +--+ | MAG | | | |Server| | +--------+ +------+ +------+ | | | | | | | | (1)|-ATTACH--->| | | (2)| |PBU[Civic Loc, Update-Timer]--->| | | | | | (3)| |<-----PBA[Update-Timer]---------| | | | | | (4)| | |<-Get Loc----| | | | | | | check ANI | | | Timer | (5)| |<-Update Notification-----------| | | | (ANI-PARAMS-Requested) | | | | | | (6)| |---Update Notification Ack----->| | (7)| |PBU[Civic Loc, Update-Timer]--->| | (8)| |<-----PBA[Update-Timer]---------| | (9)| | |---Location->| Figure 4: Usage Example Note the the protocol for retrieving location from the LMA is outside the scope of this document. 7. IANA Considerations This document requires the following IANA action. o Action-1: This specification defines a new Access Network Identifier sub-option called Civic Location Sub-option. This mobility sub-option is described in Section 3 and this sub-option can be carried in Access Network Identifier mobility option. The type value for this sub-option needs to be allocated from the registry "Access Network Information (ANI) Sub-Option Type Values". RFC Editor: Please replace in Section 3 with the assigned value, and update this section accordingly. o Action-2: This specification defines a new Access Network Identifier sub-option called MAG Group Identifier Sub-option. This mobility sub-option is described in Section 4 and this sub- option can be carried in Access Network Identifier mobility option. The type value for this sub-option needs to be allocated from the registry "Access Network Information (ANI) Sub- Pazhyannur, et al. Expires August 18, 2014 [Page 8] Internet-Draft Extensions to ANI February 2014 Option Type Values". RFC Editor: Please replace in Section 4 with the assigned value, and update this section accordingly. o Action-3: This specification defines a new Access Network Identifier sub-option called ANI-Update-Frequency Sub-option. This mobility sub-option is described in Section 5 and this sub- option can be carried in Access Network Identifier mobility option. The type value for this sub-option needs to be allocated from the registry "Access Network Information (ANI) Sub- Option Type Values". RFC Editor: Please replace in Section 5 with the assigned value, and update this section accordingly. 8. Security Considerations The Civic Location and the ANI-Update-Frequency sub-Options defined in this specification are to be carried in the Access Network Identifier option defined in [RFC6757]. This sub-option is carried in Proxy Binding Update and Proxy Binding Acknowledgement messages. This sub-option is carried like any other Access Network Identifier sub-option as defined in [RFC6757]. Therefore, it inherits from [RFC5213] and [RFC6757], its security guidelines and does not require any additional security considerations. The Civic Location sub-option carried in the Access Network Information option exposes the geo-location of the network to which the mobile node is attached. This information is considered to be very sensitive, so care must be taken to secure the Proxy Mobile IPv6 signaling messages when carrying this sub-option. The base Proxy Mobile IPv6 specification [RFC5213] specifies the use of IPsec for securing the signaling messages, and those mechanisms can be enabled for protecting this information. Operators can potentially apply IPsec Encapsulating Security Payload (ESP) with confidentiality and integrity protection for protecting the location information. Access-network-specific information elements that the mobile access gateway sends may have been dynamically learned over DHCP or using other protocols. If proper security mechanisms are not in place, the exchanged information may be potentially compromised with the mobile access gateway sending incorrect access network parameters to the local mobility anchor. This situation may potentially result in incorrect service policy enforcement at the local mobility anchor and impact to other services that depend on this access network information. This threat can be mitigated by ensuring the communication path between the mobile access gateway and the access points is properly secured by the use of IPsec, Transport Layer Pazhyannur, et al. Expires August 18, 2014 [Page 9] Internet-Draft Extensions to ANI February 2014 Security (TLS), or other security protocols. 9. Acknowledgements TBD 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4776] Schulzrinne, H., "Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Option for Civic Addresses Configuration Information", RFC 4776, November 2006. [RFC5139] Thomson, M. and J. Winterbottom, "Revised Civic Location Format for Presence Information Data Format Location Object (PIDF-LO)", RFC 5139, February 2008. [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. [RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy Mobile IPv6", RFC 5844, May 2010. [RFC6757] Gundavelli, S., Korhonen, J., Grayson, M., Leung, K., and R. Pazhyannur, "Access Network Identifier (ANI) Option for Proxy Mobile IPv6", RFC 6757, October 2012. 10.2. Informative References [RFC5415] Calhoun, P., Montemurro, M., and D. Stanley, "Control And Provisioning of Wireless Access Points (CAPWAP) Protocol Specification", RFC 5415, March 2009. [RFC5416] Calhoun, P., Montemurro, M., and D. Stanley, "Control and Provisioning of Wireless Access Points (CAPWAP) Protocol Binding for IEEE 802.11", RFC 5416, March 2009. Pazhyannur, et al. Expires August 18, 2014 [Page 10] Internet-Draft Extensions to ANI February 2014 Authors' Addresses Rajesh S. Pazhyannur Cisco 170 West Tasman Drive San Jose, CA 95134, USA Email: rpazhyan@cisco.com Sebastian Speicher Cisco Richtistrasse 7 Wallisellen, Zurich, 8304 Switzerland Email: sespeich@cisco.com Sri Gundavelli Cisco 170 West Tasman Drive San Jose, CA 95134 USA Email: sgundave@cisco.com Jouni Korhonen Broadcom Porkkalankatu 24 Helsinki FIN-00180 Finland Email: jouni.nospam@gmail.com Pazhyannur, et al. Expires August 18, 2014 [Page 11]