Network Working Group S. Bhandari Internet-Draft S. Gundavelli Intended status: Standards Track Cisco Systems Expires: October 18, 2013 J. Korhonen Renesas Mobile M. Grayson Cisco Systems April 16, 2013 Access-Network-Identifier Option in DHCP draft-bhandari-dhc-access-network-identifier-04 Abstract This document specifies the format and mechanism that is to be used for encoding access network identifiers in DHCPv4 and DHCPv6 messages by defining new access network identifier options and sub-options. Requirements Language 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]. 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 October 18, 2013. Copyright Notice Copyright (c) 2013 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 Bhandari, et al. Expires October 18, 2013 [Page 1] Internet-Draft DHCPv4 & v6 ANI options April 2013 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 . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. DHCPv4 Access-Network-Identifier Option . . . . . . . . . . . 5 4.1. DHCPv4 Access-Network-Identifier Sub-options . . . . . . . 5 5. DHCPv6 Access-Network-Identifier options . . . . . . . . . . . 6 6. DHCPv4 and DHCPv6 Access-Network-Identifier Options . . . . . 6 6.1. Access-Network-Type option . . . . . . . . . . . . . . . . 6 6.2. Network-Identifier options . . . . . . . . . . . . . . . . 8 6.3. Operator identifier options . . . . . . . . . . . . . . . 11 7. Client Behavior . . . . . . . . . . . . . . . . . . . . . . . 12 8. Relay Agent Behavior . . . . . . . . . . . . . . . . . . . . . 13 9. Server Behavior . . . . . . . . . . . . . . . . . . . . . . . 13 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 11. Security Considerations . . . . . . . . . . . . . . . . . . . 14 12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14 13. Change log . . . . . . . . . . . . . . . . . . . . . . . . . . 14 14. Normative References . . . . . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16 Bhandari, et al. Expires October 18, 2013 [Page 2] Internet-Draft DHCPv4 & v6 ANI options April 2013 1. Introduction Access network identification of a network device has a range of application. For e.g. The local mobility anchor in a Proxy Mobile IPv6 domain is able to provide access network and access operator specific handling or policing of the mobile node traffic using information about the access network to which the mobile node is attached. This document specifies Dynamic Host Configuration Protocol v4 (DHCPv4) [RFC2131] and Dynamic Host Configuration Protocol v6 (DHCPv6) [RFC3315] options for access network identification that is added by Client or Relay agent in the DHCPv4 or DHCPv6 messages towards the Server. Dynamic Host Configuration Protocol (DHCP) client or DHCP relay agent aware of the access network and access operator add this information in the DHCP messages. This information can be used to provide differentiated services and policing of traffic based on the access network to which a client is attached. Examples of how this information can be used in mobile networks can be found in [RFC6757] 2. Motivation Proxy mobile IPv6 [RFC5213] can be used for supporting network-based mobility management in various type of network deployments. The network architectures, such as Service provider Wi-Fi access aggregation or, WLAN integrated mobile packet core are examples where Proxy Mobile IPv6 is a component of the overall architecture. Some of these architectures require the ability of the local mobility anchor (LMA) [RFC5213] to provide differentiated services and policing of traffic to the mobile nodes based on the access network to which they are attached. Policy systems in mobility architectures such as PCC [TS23203] and ANDSF [TS23402] in 3GPP system allow configuration of policy rules with conditions based on the access network information. For example, the service treatment for the mobile node's traffic may be different when they are attached to a access network owned by the home operator than when owned by a roaming partner. The service treatment can also be different based on the configured Service Set Identifiers (SSID) in case of IEEE 802.11 based access networks. Other examples of services include the operator's ability to apply tariff based on the location. The PMIPv6 extension as specified in [RFC6757] defines PMIPv6 options to carry access network identifiers in PMIPv6 signaling from Mobile Access Gateway (MAG) to LMA. MAG can learn this information from DHCP options as inserted by DHCP client or Relay agent before MAG. Bhandari, et al. Expires October 18, 2013 [Page 3] Internet-Draft DHCPv4 & v6 ANI options April 2013 If MAG relays DHCP messages to LMA as specified in [RFC5844] this information can be inserted by MAG towards LMA in the forwarded DHCP messages. Figure 1 illustrates an example Proxy Mobile IPv6 deployment where Access Points (AP) inserts access network identifiers in DHCP messages. The mobile access gateway learns this information over DHCP and delivers the information elements related to the access network to the local mobility anchor over Proxy Mobile IPv6 signaling messages. In this example, the additional information could comprise the SSID of the used IEEE 802.11 network and the identities of the operators running the IEEE 802.11 access network infrastructure. SSID: IETF-1 Operator-Id: provider1.example.com +--+ DHCP |AP|-------. {Access Specific Policies) +--+ | _-----_ | +-----+ _( )_ +-----+ | MAG |-=====( PMIPv6 )======-| LMA |- +-----+ (_ Tunnel_) +-----+ +--+ DHCP | '-----' |AP|-------' +--+ SSID: IETF-2 Operator-Id: provider2.example.com Access Networks attached to MAG 3. Terminology All the DHCP related terms used in this document to be interpreted as defined in the Dynamic Host Configuration Protocol v4 (DHCPv4) [RFC2131] and Dynamic Host Configuration Protocol v6 (DHCPv6) [RFC3315] specifications. DHCP refers to both DHCPv4 and DHCPv6 messages and entities throughout this document. All the mobility related terms used in this document are to be interpreted as defined in the Proxy Mobile IPv6 specifications [RFC5213] and [RFC5844]. Additionally, this document uses the following abbreviations: Service Set Identifier Service Set Identifier (SSID) identifies the name of the IEEE 802.11 network. SSID differentiates from one network to the other. Bhandari, et al. Expires October 18, 2013 [Page 4] Internet-Draft DHCPv4 & v6 ANI options April 2013 Vendor ID The Vendor ID is the SMI Network Management Private Enterprise Code of the IANA-maintained Private Enterprise Numbers registry [SMI]. 4. DHCPv4 Access-Network-Identifier Option Access network identifier option carries information to identify the access network to which the client is attached to. This information includes access technology type, network identifier and access network operator identifiers. The format of the DHCPv4 Access-Network-Identifier option is shown below. Code Len ANI Sub-options +------+------+------+------+------+-- --+-----+ | code | len | s1 | s2 | s2 | ... | sn | +------+------+------+------+------+-- --+-----+ code: 8-bit code carrying Access Network Identifier sub-options, If added by relay agent: Relay Agent Information Option (82) If added by client: OPTION_ACCESS_NETWORK_ID (TBD1) len: 8 bit indicating total length of the included suboptions. ANI Sub-options: The ANI Sub-options consists of a sequence of SubOpt/Length/Value tuples for each sub-option, encoded in the following manner: SubOpt Len Sub-option Value +------+------+------+------+------+------+--...-+------+ | code | N | s1 | s2 | s3 | s4 | | sN | +------+------+------+------+------+------+--...-+------+ ANI Sub-options are defined in following sections. 4.1. DHCPv4 Access-Network-Identifier Sub-options Access network identifier information will be defined in multiple sub-options. The initial assignment of DHCP access network identifier Sub-options is as follows: Bhandari, et al. Expires October 18, 2013 [Page 5] Internet-Draft DHCPv4 & v6 ANI options April 2013 Sub-option Code Sub-Option Description --------------- ---------------------- TBD7 Access-Network-Type Sub-option TBD8 Network-Name Sub-option TBD9 AP-Name Sub-option TBD10 Operator-Identifier Sub-option TBD11 Operator-Realm Sub-option 5. DHCPv6 Access-Network-Identifier options The Access Network Identifier option defined here will be added by DHCPv6 client in upstream DHCPv6 messages or by the Relay in Relay- forward messages. Option Code Descrption --------------- ---------------------- TBD2 OPTION_ANI_ATT TBD3 OPTION_ANI_NETWORK_NAME TBD4 OPTION_ANI_AP_NAME TBD5 OPTION_ANI_OPERATOR_ID TBD6 OPTION_ANI_OPERATOR_REALM 6. DHCPv4 and DHCPv6 Access-Network-Identifier Options This section defines DHCPv4 suboption and DHCPv6 options for access network identification. 6.1. Access-Network-Type option This option is used for exchanging the type of the access technology the client is attached to the network. There can only be a single instance of this specific option in any DHCPv6 message or single instance of this specific sub-option in DHCPv4 OPTION_ACCESS_NETWORK_ID or Relay Agent information option. Its format is as follows: Bhandari, et al. Expires October 18, 2013 [Page 6] Internet-Draft DHCPv4 & v6 ANI options April 2013 DHCPv4: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | suboption-code| Length | ATT | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ suboption-code: 8-bit code, it should be set to value of (TBD7), indicating that its a Access-Network-Type sub-option Length: 8-bit unsigned integer indicating the length of this suboption in octets, excluding the suboption-code and length fields. This field MUST be set to 2. DHCPv6: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Option Code (TBD2) | OptLen | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ATT + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: 16-bit code OPTION_ANI_ATT (TBD2) option-length: 16-bit unsigned integer indicating length in octets of this option Common format applicable to DHCPv4 and DHCPv6: Access Technology Type (ATT) An 16-bit field that specifies the access technology through which the client is connected to the access link. The values is as populated from the IANA name space Access Technology Type Option type values as requested in [RFC5213] 0: Reserved ("Reserved") 1: Virtual ("Logical Network Interface") 2: PPP ("Point-to-Point Protocol") 3: IEEE 802.3 ("Ethernet") 4: IEEE 802.11a/b/g ("Wireless LAN") 5: IEEE 802.16e ("WIMAX") Bhandari, et al. Expires October 18, 2013 [Page 7] Internet-Draft DHCPv4 & v6 ANI options April 2013 6.2. Network-Identifier options These options can be used for carrying the name of the access network (e.g., a SSID in case of IEEE 802.11 Access Network, or PLMN Identifier [TS23003] in case of 3GPP access ) and Access Point name, to which the client is attached. There can only be a single instance of each of these options in any DHCPv6 message or single instance of each of these sub-options in DHCPv4 OPTION_ACCESS_NETWORK_ID or Relay Agent information option. The format of these options is defined below. DHCPv4: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |suboption code | Length | ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Network Name (e.g., SSID or PLMNID) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ suboption code: 8-bit code, it should be set to value of (TBD8), indicating that its a Network-Name sub-option Length: 8-bit indicating Total length of this sub option, excluding the suboption code and length fields. The value can be in the range of 2 to 32 octets. DHCPv6: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Option Code (TBD3) | OptLen | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Network Name (e.g., SSID or PLMNID) ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: 16-bit code OPTION_ANI_NETWORK_NAME (TBD3) option-length: 16-bit unsigned integer indicating length in octets of this option.The value can be in the range of 2 to 32 octets. Common format applicable to DHCPv4 and DHCPv6: Bhandari, et al. Expires October 18, 2013 [Page 8] Internet-Draft DHCPv4 & v6 ANI options April 2013 Network Name: The name of the access network to which the mobile node is attached. The type of the Network Name is dependent on the access technology to which the mobile node is attached. If it is 802.11 access, the Network Name MUST be the SSID of the network. If the access network is 3GPP access, the Network Name is the PLMN Identifier of the network. If the access network is 3GPP2 access, the Network Name is the Access Network Identifier [ANI]. When encoding the PLMN Identifier, both the Mobile Network Code (MNC) [TS23003] and Mobile Country Code (MCC) [TS23003] MUST be 3 digits. If the MNC in use only has 2 digits, then it MUST be preceded with a '0'. Encoding MUST be UTF-8. Bhandari, et al. Expires October 18, 2013 [Page 9] Internet-Draft DHCPv4 & v6 ANI options April 2013 DHCPv4: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |suboption code | Length | ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Access-Point Name ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ suboption code: 8-bit code, it should be set to value of (TBD9), indicating that its a Network-AP-Name sub-option Length: 8-bit indicating Total length of this sub option, excluding the suboption code and length fields. The value can be in the range of 2 to 32 octets. DHCPv6: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Option Code (TBD3) | OptLen | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Access-Point Name ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: 16-bit code OPTION_ANI_AP_NAME (TBD4) option-length: 16-bit unsigned integer indicating length in octets of this option.The value can be in the range of 2 to 32 octets. Common format applicable to DHCPv4 and DHCPv6: Access-Point Name: The name of the access point (physical device name) to which the mobile node is attached. This is the identifier that uniquely identifies the access point. While Network Name (e.g., SSID) identifies the operator's access network, Access-Point Name identifies a specific network device in the network to which the mobile node is attached. In some deployments, the Access-Point Name can be set to the Media Access Control (MAC) address of the device or some unique identifier that can be used by the policy systems in the operator network to unambiguously identify the device. The string is carried in UTF-8 representation. Bhandari, et al. Expires October 18, 2013 [Page 10] Internet-Draft DHCPv4 & v6 ANI options April 2013 6.3. Operator identifier options The Operator identifier options can be used for carrying the operator identifier of the access network to which the client is attached.There can only be a single instance of each of these options in any DHCPv6 message or single instance of each of these sub-options in DHCPv4 OPTION_ACCESS_NETWORK_ID or Relay Agent information option. The format of these options is defined below. DHCPv4: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | suboptioncode | Length | ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Operator Enterprise ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ suboption code: 8 bit code, It should be set to value of (TBD10), indicating that it is Operator-Identifier sub-option Length: Total length of this sub option, excluding the suboption code and length fields. DHCPv6: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Option Code (TBD4) | OptLen | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Operator Enterprise ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: 16-bit code OPTION_ANI_OPERATOR_ID (TBD5) option-length: 16-bit unsigned integer indicating length in octets of this option. Common format applicable to DHCPv4 and DHCPv6: Operator Enterprise ID: Vendor ID as a four octet Private Enterprise Number [SMI]. Bhandari, et al. Expires October 18, 2013 [Page 11] Internet-Draft DHCPv4 & v6 ANI options April 2013 DHCPv4: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | suboptioncode | Length | ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Operator Realm ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ suboption code: 8 bit code, It should be set to value of (TBD11), indicating that it is Operator-Realm sub-option Length: Total length of this sub option, excluding the suboption code and length fields. DHCPv6: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Option Code (TBD4) | OptLen | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Operator Realm ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: 16-bit code OPTION_ANI_OPERATOR_REALM (TBD6) option-length: 16-bit unsigned integer indicating length in octets of this option. Common format applicable to DHCPv4 and DHCPv6: Operator Realm: Realm of the operator. Realm names are required to be unique, and are piggybacked on the administration of the DNS namespace. Realms are encoded using a domain name encoding defined in [RFC1035].Up to 253 octets of the operator realm. 7. Client Behavior All hosts or clients MAY include access network identifier options in all the upstream DHCP messages to inform the receiver about the access network it is attached to. Bhandari, et al. Expires October 18, 2013 [Page 12] Internet-Draft DHCPv4 & v6 ANI options April 2013 8. Relay Agent Behavior DHCP Relay Agents MAY include these options before forwarding the DHCP message to provide information about the access network over which DHCP messages from the client is received. 9. Server Behavior If DHCP Server is unable to understand this option it MUST be ignored. There is no requirement that a server return this option and its data in a downstream DHCP message. If DHCP Server is able to process these options it MAY use it for address pool selection policy decisions if configured. It MAY store this information along with the lease for logging and audit purpose. 10. IANA Considerations This document defines DHCPv4 Access Network Identifier option which requires assignment of DHCPv4 option code TBD1 assigned from "Bootp and DHCP options" registry (http://www.iana.org/assignments/ bootp-dhcp-parameters/bootp-dhcp-parameters.xml), as specified in [RFC2939]. IANA is requested to assign Sub-option codes for the following DHCPv4 Sub-options from the "DHCP Relay Agent Sub-Option Codes" Sub-option Code Sub-Option Description --------------- ---------------------- TBD7 Access-Network-Type Sub-option TBD8 Network-Name Sub-option TBD9 AP-Name Sub-option TBD10 Operator-Identifier Sub-option TBD11 Operator-Realm Sub-option IANA is requested to assign option codes for the following DHCPv6 options from the "DHCPv6 and DHCPv6 options" registry (http:// www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xml). Bhandari, et al. Expires October 18, 2013 [Page 13] Internet-Draft DHCPv4 & v6 ANI options April 2013 Option Code Descrption --------------- ---------------------- TBD2 OPTION_ANI_ATT TBD3 OPTION_ANI_NETWORK_NAME TBD4 OPTION_ANI_AP_NAME TBD5 OPTION_ANI_OPERATOR_ID TBD6 OPTION_ANI_OPERATOR_REALM 11. Security Considerations Since there is no privacy protection for DHCP messages, an eavesdropper who can monitor the link between the DHCP server, relay agent and client can discover access network information. To minimize the unintended exposure of this information, this option SHOULD be included by DHCP entities only when it is configured. Where critical decisions might be based on the value of this option, DHCP authentication as defined in "Authentication for DHCP Messages" [RFC3118] and "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)" [RFC3315] SHOULD be used to protect the integrity of the DHCP options. Link-layer confidentiality and integrity protection may also be employed to reduce the risk of disclosure and tampering. Security issues related DHCPv6 are described in section 23 of [RFC3315]. 12. Acknowledgements The authors would like to thank Kim Kinnear, Ted Lemon, Gaurav Halwasia, Bernie Volz for their valuable inputs. 13. Change log Changes from 00 - 01 o Modified v4 top level option to be either option 82 if added by relay or a new top level option if added by client o Removed DHCPv6 container option o Reorganized the options to converge v4 and v6 option descriptions Changes from 01-02 Bhandari, et al. Expires October 18, 2013 [Page 14] Internet-Draft DHCPv4 & v6 ANI options April 2013 o Modified v4 DHCP option format to align with the 1 byte code, len o Corrected typos Changes from 02-03 o No change Changes from 03-04 o split network name and ap name into separate options, removed E bit allowing different encoding o corrected the option code, type alignment to match the boundary o split operater id into enterprise id and realm as separate options 14. Normative References [ANI] "Interoperability Specification (IOS) for High Rate Packet Data (HRPD) Radio Access Network Interfaces with Session Control in the Access Network, A.S0008-A v3.0", October 2008. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997. [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998. [RFC2939] Droms, R., "Procedures and IANA Guidelines for Definition of New DHCP Options and Message Types", BCP 43, RFC 2939, September 2000. [RFC3118] Droms, R. and W. Arbaugh, "Authentication for DHCP Messages", RFC 3118, June 2001. [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003. [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. Bhandari, et al. Expires October 18, 2013 [Page 15] Internet-Draft DHCPv4 & v6 ANI options April 2013 [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. [SMI] "PRIVATE ENTERPRISE NUMBERS, SMI Network Management Private Enterprise Codes", February 2011. [TS23003] "Numbering, addressing and identification", 2011. [TS23203] "Policy and Charging Control Architecture", 2012. [TS23402] "Architecture enhancements for non-3GPP accesses", 2012. Authors' Addresses Shwetha Bhandari Cisco Systems Cessna Business Park, Sarjapura Marathalli Outer Ring Road Bangalore, KARNATAKA 560 087 India Phone: +91 80 4426 0474 Email: shwethab@cisco.com Sri Gundavelli Cisco Systems 170 West Tasman Drive San Jose, CA 95134 USA Email: sgundave@cisco.com Jouni Korhonen Renesas Mobile Linnoitustie 6 FIN-02600 Espoo, Finland Phone: Email: jouni.nospam@gmail.com Bhandari, et al. Expires October 18, 2013 [Page 16] Internet-Draft DHCPv4 & v6 ANI options April 2013 Mark Grayson Cisco Systems 11 New Square Park Bedfont Lakes, FELTHAM TW14 8HA ENGLAND Email: mgrayson@cisco.com Bhandari, et al. Expires October 18, 2013 [Page 17]