NETEXT WGInternet Engineering Task Force (IETF) R. PazhyannurInternet-DraftRequest for Comments: 7563 S. Speicher Updates: 6757(if approved)S. GundavelliIntended status:Category: Standards Track Cisco SystemsExpires: September 23, 2015ISSN: 2070-1721 J. Korhonen Broadcom Corporation J. Kaippallimalil HuaweiMarch 22,June 2015 Extensions to thePMIPv6Proxy Mobile IPv6 (PMIPv6) Access Network Identifier Optiondraft-ietf-netext-ani-location-09.txtAbstract The Access Network Identifier (ANI)Mobilitymobility option was introduced inAccessRFC 6757, "Access Network Identifier (ANI) Option for Proxy MobileIPv6 (RFC 6757).IPv6". This enables aMobilityMobile Access Gateway (MAG) to convey identifiers like the network identifier, geolocation, and operator identifier. This specification extends the Access Network Identifier mobility option withsub optionssub-options to carry the civic location and the MAG groupIdentifier.identifier. This specification also defines an ANIUpdate-Timer sub optionUpdate- Timer sub-option that determines when and how often the ANI option will be updated. Status of This Memo ThisInternet-Draftissubmitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documentsan Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF).Note that other groups may also distribute working documents as Internet-Drafts. The listIt represents the consensus ofcurrent Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents validthe IETF community. It has received public review and has been approved fora maximumpublication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status ofsix monthsthis document, any errata, and how to provide feedback on it may beupdated, replaced, or obsoleted by other documentsobtained atany 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 September 23, 2015.http://www.rfc-editor.org/info/rfc7563. Copyright Notice Copyright (c) 2015 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 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 . . . . . . . . . . . . . . . . . . . . . . . .23 2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4 2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 3. Protocol Extension . . . . . . . . . . . . . . . . . . . . .45 3.1.Civic LocationCivic-Location Sub-Option . . . . . . . . . . . . . . . .45 3.2.MAG Group identifierMAG-Group-Identifier Sub-Option . . . . . . . . . . . . .56 3.3. ANI Update-Timer Sub-Option . . . . . . . . . . . . . . . 6 4. Protocol Considerations . . . . . . . . . . . . . . . . . . .67 4.1. MAG Considerations . . . . . . . . . . . . . . . . . . .67 4.2. LMA Considerations . . . . . . . . . . . . . . . . . . . 8 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . .89 6. Security Considerations . . . . . . . . . . . . . . . . . . .910 7.AcknowledgementsReferences . . . . . . . . . . . . . . . . . . . . . .10 8. References. . . 11 7.1. Normative References . . . . . . . . . . . . . . . . . . 11 7.2. Informative References . . . . .10 8.1. Normative References. . . . . . . . . . . . 11 Acknowledgements . . . . . .10 8.2. Informative References. . . . . . . . . . . . . . . . .11. 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . .1112 1. IntroductionAccess"Access Network Identifier (ANI) Option for Proxy MobileIPv6IPv6" [RFC6757] introduced theAccess Network Identifier (ANI)ANI mobilityOption.option. This enabled aMobilityMobile Access Gateway (MAG) to provide theNetwork Identifier, geolocation,Network-Identifier, Geo-Location, and Operator-Identifiersub options.sub-options. When the access network is WLAN, theNetwork Identifier sub optionNetwork-Identifier sub-option may contain the Service Set Identifier (SSID) and the Basic Service Set Identifier (BSSID) of the Access Point(AP),(AP) and the geolocation of the AP, and theOperator-IdentifierOperator- Identifier may contain the realm of the operator managing the WLAN. The MAG sends the above information to the Local Mobility Anchor (LMA). The LMA may use this information to determineaccess networkaccess-network- specific policies (in terms of Quality of Service (QoS), Deep Packet Inspection (DPI), etc.). Further, the LMA may make this information available tolocation basedlocation-based applications. While the above mentionedsub optionssub-options provide a rich set of information, in this document we describe the need for extending the ANIsub options,sub-options that are particularly useful in WLAN deployments. In WLAN deployments (especially indoor AP deployments), it is difficult to provideGeo-spatialgeospatial coordinates of APs. At the same time, for manylocation basedlocation-based applications the civic location is sufficient. This motivates the need foraan ANIcivic location sub option.Civic-Location sub-option. In many deployments, operators tend to create groups of APs into "AP-Groups". These groups have a group identifier. The group identifier is used as a proxy for coarse location (such as the floor of abuilding,building or a small building). The group identifier may also be used to provide a common policy (e.g., QoS, charging, DPI) for all APs in that group. This specification provides asub optionsub-option for the MAG to convey a group identifier to the LMA. The provisioning of the group identifier is outside the scope of this specification and is typically done via a configuration mechanism such as CLI(Command(Command- lineInterface),Interface) or viaCAPWAP ([RFC5415], [RFC5416]), etc.Control and Provisioning of Wireless Access Points (CAPWAP) [RFC5415] [RFC5416]. This document also provides a newsub optionsub-option that determines how often the MAG will update the ANI. In typical deployments, it is expected that the MAG will update the ANI as soon as it changes. This is certainly true when the MAG is co-located with the AP. When a client roams from one AP to another AP, the MAG on the roamed (or sometimes referred to as the target) AP will provide the new ANI (forexampleexample, the network identifier and geolocation of the new AP). However, if the MAG is co-located with an Access Controller (also known as Wireless LAN Controller (WLC)), then a client roaming from one AP to another AP does not necessarily perform an ANI update. The WLC handles client mobility between APs and as a result, intra-WLC mobility is hidden from the LMA. In such deployments, the information conveyed in the ANI sub-options(e.g.(e.g., location) becomes stale and is only refreshed at the time of lifetime expiry. The MAG could deal with this by sending a Proxy Binding Update (PBU) whenever a client moves between APs just for the purpose of updating the ANIsub option.sub-option. Alternately, thisdraftdocument allows the LMA to determine how often it wants to know about the changes in the ANIsub option. Forsub-option; for example, in some cases the LMA may not care about the ANIsub optionsub-option except at the time of initialbindingbinding, or in some cases it may care about every APtransitions.transition. Thesub optionsub-option allows the LMA to tell the MAG the desired update frequency. As always, mobility events orre- registrationre-registration events will update the ANIsub options.Thesub-options. The LMA can use the ANI Update-Timer option to set the maximum frequency at which it wants to receive ANI updates. This is particularly useful in environments where a MAG covers a large number of Wi-Fi APs and there is high client mobility between theAPsAPs; forexampleexample, in a stadium Wi-Fideployment. For example,deployment, if a LMA does not want ANI updates any more often than 100 seconds, then it can propose 100 seconds as the value for ANI Update-Timer. [RFC6757] provides ANIsub optionssub-options to carry geolocation information. In thisdocumentdocument, we provide additionalsub optionssub-options to carry the civiclocation,location and group identifier. This document also defines an ANIsub optionsub-option to enable a MAG to communicate how often the MAG will update the ANI information. 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 of themobility relatedmobility-related terms used in this document are to be interpreted as defined in [RFC5213] and [RFC5844]. In this document, Civic Location is defined as follows. Civic Location: There are two common ways to identify the location of an object, either through geospatial coordinates or byso-calledso- called civic addresses. Geospatial coordinates indicate longitude, latitude, and altitude, while civic addresses indicate a street address or sometimes the location within a building (such as a room number). Civic location refers to the civic address. 3. Protocol Extension 3.1.Civic LocationCivic-Location Sub-Option Thecivic locationCivic-Location is a mobilitysub optionsub-option carried in the Access Network Identifier option defined in [RFC6757]. Thissub optionsub-option carries the civic location information of the mobile node as known to the MAG. The format of this option is defined below. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |ANIType=IANA-1|Type=4 | ANI Length | Format | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | civic location ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1:Network-Identifier Sub-optionCivic-Location Sub-Option ANI Type:<IANA-1>4 ANI Length: Total length of thissub optionsub-option in octets, excluding the ANI Type and ANIlengthLength fields. Format: This specifies the encoding format of the civic location. The value 0 is defined in this specification as described below. The remaining values (1 through 255) are reserved. 0: This value denotes Binary Encoding. The location format is based on the encoding format defined in Section 3.1 of [RFC4776], whereby the first 3 octets are not put into the civic location field (i.e., the code for the DHCP option, the length ofthe DHCP option,the DHCP option, and the 'what' element are not included). What is included is the two-octet country code field, followed by one or more civic address elements. The country-code is a two-letter ISO 3166 country code in capital ASCII letters, e.g., US. The structure of the civic address elements that follow the country code field is as defined in Section 3.3 of [RFC4776]. Reserved: This MUST be set to zero when sending andthe 'what' element are not included).ignored when received. civic location: This field will contain the civic location. The format (encoding) type is specified in the format field of thissub option.sub-option. Note that the length SHALL NOT exceed 253bytes./>.bytes. 3.2.MAG Group identifierMAG-Group-Identifier Sub-Option The MAG group identifier is a mobilitysub optionsub-option carried in the Access Network Identifier option defined in [RFC6757]. The MAG group identifier identifies the group affiliation of the MAG within that Proxy Mobile IPv6 domain. The group identifier is not assumed to be globallyunique,unique across different network operators. However, the group identifier should be unique within an operator network. In domains spanning multipleoperatorsoperators, it is recommended that theoperator identifier sub optionOperator-Identifier sub-option (defined in [RFC6757]) be used in addition togroup identifier sub optionthe MAG-Group-Identifier sub-option to ensure uniqueness. When the MAG is configured with a group identifier, the MAG should send its group identifier in the PBU.(TheNote that the configuration of this identifier is outside the scope of thisspecification. Thespecification; the usage of the identifier by the LMA is left toimplementation.)implementation. The format of thissub optionsub-option is defined below. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |ANIType=IANA-2|Type=5 | ANI Length | group identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2:MAG group identifier Sub-optionMAG-Group-Identifier Sub-Option ANI Type:<IANA-2>5 ANI Length: Total length of thissub optionsub-option in octets, excluding the ANI Type and ANIlengthLength fields. The value is always 2. group identifier: This is a2 octet3-octet unsigned integer value assigned to a group of MAGs. 3.3. ANI Update-Timer Sub-Option The ANI Update-Timer is a mobilitysub optionsub-option carried in the ANI option defined in [RFC6757]. Section 4 describes how the MAG and LMA use thissub option.sub-option. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |ANIType=IANA-3|Type=6 | ANI Length | Update-Timer | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3:Network-Identifier Sub-optionANI Update-Timer Sub-Option ANI Type:<IANA-3>6 ANI Length: Total length of thissub optionsub-option in octets, excluding the ANI Type and ANIlength fieldsLength fields. The value is always 2. Update-Timer: Update-Timer is a16 bit16-bit unsigned integer. The unit of time isseconds.4 seconds (time unit of 4 seconds ensures consistency with the time units for the binding lifetime). 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. A non-zero value indicates that the MAG may not send ANI values immediately after they have changed but rather send ANI updates when the Update-Timer expires. 4. Protocol Considerations The following considerations apply to the LMA and the MAG. 4.1. MAG Considerations o The conceptual Binding Update List entry data structure maintained by the mobile access gateway, described in Section 6.1 of [RFC5213], is extended to store the access-network-related information elements associated with the current session. Specifically, the following parameters are defined: * civic location * MAG group identifier * ANI Update-Timer o If the mobile access gateway is configured to support the Access Network Informationsub optionssub-options defined in this specification, it includes this option with the specificsub optionssub-options in all PBU messages (including PBUs for lifetime extension and for deregistration) that it sends to the LMA. The Access Network Information option is constructed as specified in Section 3. o ANI Update-Timer Considerations: The MAG sets the Update-Timer based on an exchange of timer values with the LMA. When the ANI Update-TimerSub optionsub-option is carried in a PBU, it is considered as a proposed value for the Update-Timer. The LMA may change the value of the Update-Timer received in the PBU. When theLMA providedLMA-provided value for the Update-Timer is different than what is sent by the MAG, the MAG should use theLMA providedLMA-provided value. If the MAG does not receive an ANI Update-Timersub optionsub-option inPBAthe Proxy Binding Acknowledgement (PBA) (in response to sending thesub optionsub-option in the PBU), then MAG behavior is in accordance to [RFC6757]. When ANI parameters of a mobility session change, the MAG checks whether the Update-Timer has expired. If the Update-Timer has expired, the MAG sends a PBU with the ANI option. The ANI option reflects the updated access network parameters for that mobility session. If the Update-Timer has not expired, the MAG does not send a PBU. When theUpdate- TimerUpdate-Timer for a mobility session expires, the MAG checks whether the ANI parameters have changed. If the parameters have changed from the last reported values, the MAG sends a PBU with an ANI option. If the parameters have not changed, the MAG does not send a PBU (and the Update-Timer remains expired). Note that the MAG may send a PBU even before the Update-Timer expires. This could be, for example, to initiate a QoS service request to the LMA (see [RFC7222]). In such cases, the MAG must reset the Update-Timer when it sends a PBU. o If the mobile access gateway had any of the Access Network Information mobility options included in the PBU sent toaan LMA, then the PBA received from the LMA should contain the Access Network Information mobility option with the specificsub options.sub-options. If the mobile access gateway receives a PBA with a successful Status Value but without an Access Network Information mobility option, then the mobile access gateway may log the event and, based on its local policy, even proceed to terminate the mobility session. In this case, the mobile access gateway knows the LMA does not understand the Access Network Information mobility option. 4.2. LMA Considerations o The conceptual Binding Cache entry data structure maintained by the LMA, described in Section 5.1 of [RFC5213], is extended to store the access-network-related information elements associated with the current session. Specifically, the following parameters are defined: * civic location * MAG group identifier * ANI Update-Timer o On receiving a PBU message from a MAG with the ANI option, the LMA must process the option and update the corresponding fields in the Binding Cache entry. If the option is not understood by that LMA implementation, it will skip the option and process the PBU without these options. o If the received PBU message does not include the Access Network Information option, then the mobility session associated with that PBU is updated to remove any access network information elements. o If the LMA understands/supports the Access Network Identifier mobilitysub optionssub-options defined in this specification, then the LMA echoes the Access Network Identifier mobility option with the specificsub option(s)sub-option(s) that it accepted back to the mobile access gateway in a PBA. Thecivic locationCivic-Location andgroup identifier sub optionsMAG-Group-Identifier sub-options defined in this specification should not be altered by the LMA. The LMA may change the value of the ANI Update-Timersub option.sub-option. It may choose to either echo the samevalue,value or increase or decrease the timer value. For example, if the LMA does not want to receive frequent updates (as implied by the timervalue)value), it may choose to increase the value. Similarly, if the LMA needs to receive ANI updates as soon aspossiblepossible, then it may set the value to zero (0) in the PBA. 5. IANA ConsiderationsThis document requires the followingIANAaction.has registered the values described below. oAction-1:This specification defines a new Access Network Identifiersubsub- option calledcivic location Sub-option.the Civic-Location sub-option. This mobilitysubsub- option is described in Section 3.1 and thissub optionsub-option can be carried in the Access Network Identifier mobility option. The type value<IANA-1> for this sub option needs to be<4> has been allocated from the registry "Access Network Information (ANI)Sub- OptionSub-Option Type Values".RFC Editor: Please replace <IANA-1> in Section 3.1 with the assigned value, and update this section accordingly.oAction-2:This specification defines a new Access Network Identifiersubsub- option calledMAG group identifier Sub-option.the MAG-Group-Identifier sub-option. This mobilitysub optionsub-option is described in Section 3.2 and thissub optionsub-option can be carried in Access Network Identifier mobility option. The type value<IANA-2> for this sub option needs to be<5> has been allocated from the registry "Access Network Information (ANI)Sub- OptionSub-Option Type Values".RFC Editor: Please replace <IANA-2> in Section 3.2 with the assigned value, and update this section accordingly.oAction-3:This specification defines a new Access Network Identifiersubsub- option called the ANI Update-TimerSub-option.sub-option. Thissub optionsub-option is described in Section 3.3 and thissub optionsub-option can be carried in the Access Network Identifier mobility option. The type value<IANA-3> for this sub option needs to be<6> has been allocated from the registry "Access Network Information (ANI) Sub-Option Type Values".RFC Editor: Please replace <IANA-3> in Section 3.3 with the assigned value, and update this section accordingly.6. Security Considerations Thecivic location sub optionCivic-Location sub-option defined in this specification is carried in the Access Network Identifier option defined in [RFC6757]. Thissub optionsub-option is carried in PBU and PBA messages. Thissub optionsub-option is carried like any other Access Network Identifiersub optionsub-option as defined in [RFC6757]. Therefore, it inheritsfrom [RFC5213] and [RFC6757],its security guidelines from [RFC5213] and [RFC6757] and does not require any additional security considerations. Thecivic location sub option carried in the Access Network Information optionCivic-Location sub-option exposes the civic 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 thissub option.sub-option. The base Proxy Mobile IPv6 specification [RFC5213] specifies the use ofIPSecIPsec for securing the signaling messages, and those mechanisms can be enabled for protecting this information. Operators can potentially applyIPSecIPsec Encapsulating Security Payload (ESP) with confidentiality and integrity protection for protecting the location information. The other way to protect the sensitive location information of network users is of course to not send it in the first place. Users of thecivic location sub optionCivic-Location sub-option should provision location values with the highest possible level of granularity, e.g., to the province or citylevel,level rather than provisioning specific addresses. 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 between the MAG and LMA may be compromised. This situation may result in incorrect service policy enforcement at the LMA and impacttoother 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 ofIPSec,IPsec, Transport Layer Security (TLS), or other security protocols. 7.Acknowledgements This document benefited considerably from the numerous improvements proposed by Kent Leung. 8.References8.1.7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March1997.1997, <http://www.rfc-editor.org/info/rfc2119>. [RFC4776] Schulzrinne, H., "Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Option for Civic Addresses Configuration Information", RFC 4776, DOI 10.17487/RFC4776, November2006.2006, <http://www.rfc-editor.org/info/rfc4776>. [RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, DOI 10.17487/RFC5213, August2008.2008, <http://www.rfc-editor.org/info/rfc5213>. [RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy Mobile IPv6", RFC 5844, DOI 10.17487/RFC5844, May2010.2010, <http://www.rfc-editor.org/info/rfc5844>. [RFC6757] Gundavelli, S., Ed., Korhonen, J., Ed., Grayson, M., Leung, K., and R. Pazhyannur, "Access Network Identifier (ANI) Option for Proxy Mobile IPv6", RFC 6757, DOI 10.17487/RFC6757, October2012.2012, <http://www.rfc-editor.org/info/rfc6757>. [RFC7222] Liebsch, M., Seite, P., Yokota, H., Korhonen, J., and S. Gundavelli, "Quality-of-Service Option for Proxy Mobile IPv6", RFC 7222, DOI 10.17487/RFC7222, May2014. 8.2.2014, <http://www.rfc-editor.org/info/rfc7222>. 7.2. Informative References [RFC5415] Calhoun, P., Ed., Montemurro, M., Ed., and D. Stanley, Ed., "Control And Provisioning of Wireless Access Points (CAPWAP) Protocol Specification", RFC 5415, DOI 10.17487/RFC5415, March2009.2009, <http://www.rfc-editor.org/info/rfc5415>. [RFC5416] Calhoun, P., Ed., Montemurro, M., Ed., and D. Stanley, Ed., "Control and Provisioning of Wireless Access Points (CAPWAP) Protocol Binding for IEEE 802.11", RFC 5416, DOI 10.17487/RFC5416, March2009.2009, <http://www.rfc-editor.org/info/rfc5416>. Acknowledgements This document benefited considerably from the numerous improvements proposed by Kent Leung. Authors' Addresses Rajesh S. Pazhyannur Cisco Systems 170 West Tasman Drive San Jose,CACalifornia 95134USA Email:United States EMail: rpazhyan@cisco.com Sebastian Speicher Cisco Systems Richtistrasse 7 Wallisellen, Zurich 8304 SwitzerlandEmail:EMail: sespeich@cisco.com Sri Gundavelli Cisco Systems 170 West Tasman Drive San Jose,CACalifornia 95134USA Email:United States EMail: sgundave@cisco.com Jouni Korhonen BroadcomPorkkalankatu 24 Helsinki FIN-00180 Finland Email:Corporation 3151 Zanker Road San Jose, California 95134 United States EMail: jouni.nospam@gmail.com John Kaippallimalil Huawei 5340 Legacy Drive, Suite 175 Plano, Texas 75024USA Email:United States EMail: john.kaippallimalil@huawei.com