dhc G. Liu Internet-Draft ZTE Corporation Intended status: Standards Track September 29, 2011 Expires: April 1, 2012 DHCP Options for 3GPP Specific Information draft-liu-dhc-3gpp-option-00.txt Abstract This document defines a new option that can be used by DHCP clients to send to DHCP servers. This new option includes some sub-options. It also defines standard parameter format and code so that there will be no ambiguity in interoperating the information being exchanged. It may be used for scenarios interworking with non-3GPP and 3GPP network. 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 1, 2012. Copyright Notice Copyright (c) 2011 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 Liu Expires April 1, 2012 [Page 1] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Convention & Terminology . . . . . . . . . . . . . . . . . . . 4 3. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 5 4. 3GPP Specific Information Option Format . . . . . . . . . . . 7 4.1. APN Suboption Format . . . . . . . . . . . . . . . . . . . 7 4.2. PDN Type Suboption Format . . . . . . . . . . . . . . . . 7 5. DHCP Client Behavior . . . . . . . . . . . . . . . . . . . . . 9 6. DHCP Server Behavior . . . . . . . . . . . . . . . . . . . . . 10 7. Security Considerations . . . . . . . . . . . . . . . . . . . 11 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 9. Normative References . . . . . . . . . . . . . . . . . . . . . 13 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 14 Liu Expires April 1, 2012 [Page 2] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 1. Introduction The Dynamic Host Configuration Protocol (DHCP) defined in [RFC2131] provides configuration parameters to hosts on a TCP/IP based network. DHCP is built on a client-server model, where designated DHCP server allocate network addresses and deliver configuration parameters to dynamically configured hosts. The changes to [RFC2131] defined in this document defines the use of 3GPP specific option transferred to DHCP server by DHCP client. Liu Expires April 1, 2012 [Page 3] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 2. Convention & Terminology 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]. The terminology in this document is based on the definitions in [RFC2131![cents]RFC3315], in addition to the ones specified in this section 3GPP 3rd Generation Partnership Project TS Technical Specification EPC Evolved Packet Core EPS Evolved Packet System APN Access Point Name PDN Packet Data Network GTP GPRS Tunnelling Protocol PMIP Proxy Mobile IP Liu Expires April 1, 2012 [Page 4] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 3. Problem Statement In 3GPP TS 23.402, 3GPP EPS supports the use of non-3GPP IP access networks to access the EPC. When non-3GPP access is trusted, and non-3GPP access network supports Network Based Mobility protocol, UE shall send L3 attach trigger message for triggering trusted non-3GPP access to interwork with the EPC. And trusted non-3GPP access will return UE IP address by the L3 attach complete message. The figure 1 is shown as follows. +---------+ +------------------+ +--------+ +------------+ | UE | | Trusted Non-3GPP| | PDN GW | | HSS/AAA | | | | IP Access | +--------+ +------------+ +---------+ +------------------+ | | | | | | --------------------------- | | | 1.Non-3GPP Specific | | | | Procedures | | | --------------------------- | | |2.EAP Authentication | 2.Authentication&Authorization | |/-------------------\|/--------------------|-------------\| |\-------------------/|\--------------------|-------------/| | | | | --------------------------- | | | 3.L3 Attach Trigger | | | | | | | --------------------------- | | | |4.PBU/Create Session Request | | |-------------------->| 5. Update PDN GW Address | | |<------------>| | |6.PBA/Create Session Response | | |<--------------------| | | | | | --------------------------- | | | 7.L3 Attach Completion | | | | | | | --------------------------- | | Figure 1: Initial attachment over Trusted Non-3GPP Access For L3 attach trigger message, DHCP protocol is considered of preferred one. And then, UE acts as DHCP client, trusted non-3GPP access acts as DHCP server. However, during initial attachment to a trusted non-3GPP access, trusted non-3GPP access needs to get UE requested APN, requested PDN type. All the parameters are very important for trusted non-3GPP access to interwork with the EPC. Liu Expires April 1, 2012 [Page 5] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 Currently, both the DHCPv6 specification [RFC3315] and DHCPv4 specification [RFC2131] don!_t define above 3GPP specific options. This document is intended to define a new DHCP options for 3GPP specific information. Liu Expires April 1, 2012 [Page 6] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 4. 3GPP Specific Information Option Format In order to supply options for the DHCP client to send to the server, the client sends a 3GPP specific Options option in the DHCP message to DHCP server, this option encapsulates whatever suboptions the client wishes to provide to the DHCP server. 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_3GPP | option-length | suboptions... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code OPTION_3GPP (TBD) option-len The number of octets in the option, minimum 1. One or more sub-options may be specified as described below. Figure 2: 3GPP Specific Information Option Format 4.1. APN Suboption Format The purpose of APN is to identify the packet data network to which the user wishes to connect and to notify the access point of the packet data network that wishes to connect to the MS. The suboption format is referred to 3GPP TS 24.008 description. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Code | Length | Value +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Code The option code (1). Length The number of octets in the option, minimum 1. Value The APN value, the defination refer to 3GPP, minimum 1. Figure 3: APN Suboption Format 4.2. PDN Type Suboption Format Liu Expires April 1, 2012 [Page 7] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 0 0 1 2 3 4 5 6 7 8 9 +-+-+-+-+-+-+-+-+-+-+ | Code |S|Value| +-+-+-+-+-+-+-+-+-+-+ Code The option code (1). S Bit 4 of octet 1 is spare and shall be coded as zero. Value The PDN Type value, the defination is as follows, Bits 0 1 2 0 0 1 IPv4 0 1 0 IPv6 0 1 1 IPv4v6 1 0 0 unused; shall be interpreted as "IPv6" if received by the network All other values are reserved. Figure 4: APN Suboption Format Liu Expires April 1, 2012 [Page 8] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 5. DHCP Client Behavior For DHCPv4 protocol, DHCP client may include a 3GPP specific option in the option payload of DHCPDISCOVER message being sent toward a DHCP server. For DHCPv6 protocol, DHCP client may include a 3GPP specific option in the option payload of SOLICIT message being sent toward a DHCP server. When initial attach, DHCP client may include a 3GPP specific option which include requested APN, requested PDN type. And when handover from 3GPP to a trusted non-3GPP access, DHCP client may include a 3GPP specific option which include requested APN. Liu Expires April 1, 2012 [Page 9] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 6. DHCP Server Behavior DHCP server gets 3GPP specific option from received DHCPDISCOVER or SOLICIT message, and transfers these information, such as requested APN, request PDN type to 3GPP EPC by PMIP or GTP message. Liu Expires April 1, 2012 [Page 10] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 7. Security Considerations Security considerations in DHCPv4 are described in [RFC3118]. Security considerations in DHCPv6 are described in [RFC3315]. Liu Expires April 1, 2012 [Page 11] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 8. IANA Considerations IANA is requested to assign one new DHCP option code defined in section 5. Liu Expires April 1, 2012 [Page 12] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 9. Normative References [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. [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. [TS23402] 3GPP, "Architecture enhancements for non-3GPP accesses", 2011. [TS24008] 3GPP, "Mobile radio interface Layer 3 specification; Core network protocols", 2010. [TS24301] 3GPP, "Non-Access-Stratum (NAS) protocol for Evolved Packet System(EPS)", 2010. Liu Expires April 1, 2012 [Page 13] Internet-Draft DHCP Opt for 3GPP Specific Information September 2011 Author's Address Guoyan Liu ZTE Corporation No.68 Zijinghua Avenue, Yuhuatai District Nanjing China Phone: +86-25-5287-1362 Email: liu.guoyan@zte.com.cn Liu Expires April 1, 2012 [Page 14]