--- 1/draft-ietf-dhc-bcmc-options-00.txt 2006-02-04 23:01:36.000000000 +0100 +++ 2/draft-ietf-dhc-bcmc-options-01.txt 2006-02-04 23:01:36.000000000 +0100 @@ -1,280 +1,278 @@ Network Working Group K. Chowdhury Internet-Draft Starent Networks -Expires: August 28, 2005 P. Yegani +Expires: November 17, 2005 P. Yegani Cisco Systems L. Madour Ericsson - February 27, 2005 + May 16, 2005 DHCP Options for Broadcast and Multicast Control Servers - draft-ietf-dhc-bcmc-options-00.txt + draft-ietf-dhc-bcmc-options-01.txt Status of this Memo - This document is an Internet-Draft and is subject to all provisions - of section 3 of RFC 3667. By submitting this Internet-Draft, each - author represents that any applicable patent or other IPR claims of - which he or she is aware have been or will be disclosed, and any of - which he or she become aware will be disclosed, in accordance with - RFC 3668. + By submitting this Internet-Draft, each author represents that any + applicable patent or other IPR claims of which he or she is aware + have been or will be disclosed, and any of which he or she becomes + aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that - other groups may also distribute working documents as - Internet-Drafts. + other groups may also distribute working documents as Internet- + Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. - This Internet-Draft will expire on August 28, 2005. + This Internet-Draft will expire on November 17, 2005. Copyright Notice Copyright (C) The Internet Society (2005). Abstract This document defines new options for Broadcast and Multicast Service controller discovery in an IP network. Broadcast service is being - developed for 3G wireless networks. Users of the service interact - with a controller in the network to derive informations that are - required to receive broadcast service. Dynamic Host Configuration - Protocol can be used to configure the controller IPv4 addresses or - fully qualified domain names in the user's devices. This document + developed for 3rd generation (3G) cellular telephone networks. Users + of the service interact with a controller in the network via the + Mobile Node (MN) to derive information required to receive broadcast + service. Dynamic Host Configuration Protocol can be used to + configure the MN to acccess a particular controller. This document defines the related options and option codes. Table of Contents 1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Overview of the 3GPP2 BCMCS Network . . . . . . . . . . . . . 4 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Broadcast Service Controller Options . . . . . . . . . . . . . 6 - 4.1 Broadcast Service Controller Domain Name List Option - for DHCP . . . . . . . . . . . . . . . . . . . . . . . . . 6 + 4.1 Broadcast Service Controller Domain Name list . . . . . . 6 4.2 Broadcast Service Controller Domain Name List Option for DHCPv6 . . . . . . . . . . . . . . . . . . . . . . . . 7 - 4.3 Broadcast Service Controller IPv4 Address Option . . . . . 8 + 4.3 Broadcast Service Controller IPv4 address option . . . . . 8 4.4 Broadcast Service Controller IPv6 Address Option . . . . . 8 - 5. Consideration for Client Operation for DHCPv6 . . . . . . . . 9 - 6. Consideration for Server Operation . . . . . . . . . . . . . . 10 - 7. Security Considerations . . . . . . . . . . . . . . . . . . . 11 - 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 - 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13 - 10. Normative References . . . . . . . . . . . . . . . . . . . . 13 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 13 - Intellectual Property and Copyright Statements . . . . . . . . 15 + 4.5 Consideration for Client Operation . . . . . . . . . . . . 9 + 4.6 Consideration for Server Operation . . . . . . . . . . . . 9 + 5. Security Considerations . . . . . . . . . . . . . . . . . . . 10 + 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 + 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12 + 8. Normative References . . . . . . . . . . . . . . . . . . . . . 12 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 12 + Intellectual Property and Copyright Statements . . . . . . . . 14 1. Motivation Dynamic Host Configuration Protocol [RFC2131] and [RFC3315] can be used to configure various non-IP address type of parameters. These parameters are required for normal operation of various services that are offered over an IP network. Broadcast and multicast service (BCMCS) is one such service that is currently being standardized in various mobile wireless standard bodies such as 3GPP, 3GPP2 and OMA. A description of the BCMCS, for example, in 3GPP2 can be found in [BCMCS]. While DHCP offers necessary mechanisms for device configuration, it lacks the information elements required to configure a mobile device - to support BCMCS. This memo is an effort to define the extensions - needed for DHCP to provide necessary configuration information to a - mobile device in a BCMCS network. + to support BCMCS. This memo defines the extensions needed for DHCP + to provide necessary configuration information to a mobile device in + a BCMCS network. DHCP is being used in 3GPP2, for example, to assist with the - discovery of the BCMCS Controller in a mobile operators IP network. + discovery of the BCMCS Controller in a mobile operator's IP network. The BCMCS includes a controller component that is responsible for - managing the service via interaction with the users and other network + managing the service via interaction with the MN and other network entities. An overview of the 3GPP2 BCMCS architecture is given in the next section. It provides enough information to understand the basics of the 3GPP2 BCMCS operation. Readers are encouraged to find a more detailed description in [BCMCS]. - As described in [BCMCS], the users of the service are required to - know the IPv4 or the IPv6 address of the controller entity so that - they can download all the necessary information about a desired - broadcast program. In a roaming environment static configuration of - the controller's IP address becomes unrealistic. Therefore, DHCP is - considered to be a method to dynamically configure the controller's - IP address or the fully qualified domain name of the controller in - the 3G wireless networks. + As described in [BCMCS], the MNs are required to know the IPv4 or the + IPv6 address of the controller entity so that they can download all + the necessary information about a desired broadcast program. In a + roaming environment static configuration of the controller's IP + address becomes unrealistic. Therefore, DHCP is considered to be a + method to dynamically configure the MNs with the IP address or the + fully qualified domain name of the controller in the 3G cellular + telephone networks. - In order to allow the users to discover the broadcast controllers, - the clients request for appropriate option codes from the DHCP - servers using Parameter Request List option. The DHCP servers need - to return the corresponding configuration options that carry either + In order to allow the MNs to discover the broadcast controllers, the + DHCP clients request for appropriate option codes from the DHCP + server using Parameter Request List option. The DHCP servers need to + return the corresponding configuration options that carry either broadcast and multicast service controller's IP address or fully - qualified domain name based on configuration. The motivation for - this document is to define the necessary options and option codes. + qualified domain name based on configuration. This document defines + the necessary options and option codes. 2. Overview of the 3GPP2 BCMCS Network - The Broadcast and Multicast Service architecture in a 3G wireless - network such as 3GPP2 has the following model: + The Broadcast and Multicast Service architecture in a 3G cellular + telephone network such as 3GPP2 has the following model: +------------+ +--------+ | | | | | Controller | | DHCP | | | | Server | +------------+ +--------+ ^ Control| Info| | | V +----+ +------------+ +------------+ | | | | | | | MN/| bearer | Radio | | Broadcast | |User|<-------| Access |<---| Content | | | | Network | | Server | +----+ +------------+ +------------+ Note that this figure is shown here for broad understanding of how - Broadcast and Multicast service works in a 3G mobile wireless IP + Broadcast and Multicast service works in a 3G cellular telehone network. The network elements except MN/user and the DHCP server are not relevant to the text in this document. - The user interacts with the Controller to request for - broadcast/multicast program information from the network (e.g., - scheduled time, multicast IP address, port numbers). The User may - also be authenticated by the Controller while downloading the - relevant program security related information (such as encryption - key). These interactions happen via HTTP and XML. There may be more - than one controller in the network. The user should discover the - appropriate controller to request the relevant program information. - For details of Broadcast and Multicast Service operation in 3GPP2, - see [BCMCS]. + The MN interacts with the Controller to request broadcast/multicast + program information from the network (e.g., scheduled time, multicast + IP address, port numbers). The MN may also be authenticated by the + Controller while downloading the relevant program security related + information (such as encryption key). These interactions may happen + via HTTP and XML. There may be more than one controller in the + network. The MN should discover the appropriate controller to + request the relevant program information. For details of Broadcast + and Multicast Service operation in 3GPP2, see [BCMCS] 3. Terminology The keywords "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. 4. Broadcast Service Controller Options This section defines the configuration option for the controller of - Broadcast Service. The Configuration Option contains the IPv4 - address or of the IPv4 address or the fully qualified domain names of - the broadcast service controller. + the broadcast service. -4.1 Broadcast Service Controller Domain Name List Option for DHCP +4.1 Broadcast Service Controller Domain Name list + + If the 'enc' byte has a value of 0, the encoding byte is followed by + a sequence of labels, encoded according to Section 3.1 of RFC 1035 + [RFC1035]. The option MAY contain multiple domain names, but these domain names SHOULD be used to construct SRV lookups as specified in [BCMCS], rather than querying for different A records. The client MUST try the records in the order listed, applying the mechanism described in [BCMCS] for each entry. The client only resolves the subsequent domain names if attempts to contact the first one failed or yielded no common transport protocols between the client and the controller - or denote a domain administratively prohibited by client's policy. + or denote a domain that is administratively prohibited by client's + policy. - Use of multiple domain names is not meant to replace the SRV records, - but rather to allow a single DHCP server to indicate the broadcast - controllers in the access provider's network. + The use of multiple domain names is not meant to replace the SRV + records, but rather to allow a single DHCP server to indicate the + broadcast controllers in the wireless access provider's network. - Clients MUST support compression according to the encoding in Section + Clients MAY support compression according to the encoding in Section 4.1.4 of "Domain Names - Implementation And Specification [RFC1035]. - Since the domain names are supposed to be different domains, - compression will likely have little effect, however. If the length - of the domain list exceeds the maximum permissible within a single + compression will likely have little effect. If the length of the + domain list exceeds the maximum permissible length within a single option (254 octets), then the domain list MUST be represented in the DHCP message as specified in [RFC3396] . The DHCP option for this encoding has the following format: - Code Len FQDN(s) of Broadcast Controller - +-----+-----+-----+-----+-----+-----+-----+-- - | TBD | n | s1 | s2 | s3 | s4 | s5 | ... - +-----+-----+-----+-----+-----+-----+-----+-- + Code Len enc FQDN(s) of Broadcast Controller + +-----+-----+-----+-----+-----+-----+-----+-----+-- + | TBD | n | 0 | s1 | s2 | s3 | s4 | s5 | ... + +-----+-----+-----+-----+-----+-----+-----+-----+-- An example case when two controller domain names e.g. - bcmc1.carrier1.com, bcmc2.carrier1.com are returned without compression will be: + bcmc1.example.com, bcmc2.example.com are returned will be: +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ - |TBD|38 | 5 |'b'|'c'|'m'|'c'|'1'| 8 |'c'|'a'|'r'|'r'|'i'|'e'|'r'| + |TBD|38 | 5 |'b'|'c'|'m'|'c'|'1'| 8 |'e'|'x'|'a'|'m'|'p'|'l'|'e'| +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ - |'1'| 3 |'c'|'o'|'m'| 5 |'b'|'c'|'m'|'c'|'2'| 8 |'c'|'a'|'r'|'r'| + | 3 |'c'|'o'|'m'| 5 |'b'|'c'|'m'|'c'|'2'| 8 |'e'|'x'|'a'|'m'|'p'| +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+ - |'i'|'e'|'r'|'1'| 3 |'c'|'o'|'m'| - +---+---+---+---+---+---+---+---+ + |'l'|'e'|'1'| 3 |'c'|'o'|'m'| + +---+---+---+---+---+---+---+ 4.2 Broadcast Service Controller Domain Name List Option for DHCPv6 The option length is followed by a sequence of labels, encoded - according to Section 3.1 of RFC 1035 [5]. + according to Section 3.1 of RFC 1035. The option MAY contain multiple domain names, but these domain names SHOULD be used to construct SRV lookups as specified in [BCMCS], rather than querying for different A records. The client MUST try the records in the order listed, applying the mechanism described in [BCMCS] for each entry. The client only resolves the subsequent domain names if attempts to contact the first one failed or yielded no common transport protocols between the client and the controller or denote a domain administratively prohibited by client's policy. Use of multiple domain names is not meant to replace the SRV records, but rather to allow a single DHCPv6 server to indicate the broadcast controllers in the access provider's network. The DHCPv6 option for Boradcast Service Controller Domain Names has the format shown below. - option-code: OPTION_BCMCS_SERVER_D (TBD) + option-code: OPTION_BCMCS_SERVER_D (TBD). option-length: Length of the 'Broadcast Control Server Domain Name List' field in octets; variable. 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_BCMCS_SERVER_D | option-length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Broadcast Control Domain Name List | | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -4.3 Broadcast Service Controller IPv4 Address Option +4.3 Broadcast Service Controller IPv4 address option - If the 'enc' byte has a value of 1, the encoding byte is followed by - a list of IPv4 addresses indicating broadcast controller IPv4 - addresses. The controllers MUST be listed in order of preference. - Its minimum length is 5, and the length MUST be a multiple of 4 plus - one. The DHCP option for this encoding has the following format: + The encoding byte (enc) is followed by a list of IPv4 addresses + indicating broadcast controller IPv4 addresses. The controllers MUST + be listed in order of preference. Its minimum length is 5, and the + length MUST be a multiple of 4 plus one. The DHCP option for this + encoding has the following format: - Code Len Address 1 Address 2 - +-----+-----+-----+-----+-----+-----+-----+-- - | TBD | n | a1 | a2 | a3 | a4 | a1 | ... - +-----+-----+-----+-----+-----+-----+-----+-- + Code Len enc Address 1 Address 2 + +-----+-----+-----+-----+-----+-----+-----+-----+-- + | TBD | n | 1 | a1 | a2 | a3 | a4 | a1 | ... + +-----+-----+-----+-----+-----+-----+-----+-----+-- 4.4 Broadcast Service Controller IPv6 Address Option This DHCPv6 option MUST carry one or more 128-bit IPv6 address(es) of the Broadcast Service Controller in a operators network. - option-code: OPTION_BCMCS_SERVER_A (TBD) + option-code: OPTION_BCMCS_SERVER_A (TBD). option-length: Length of the 'Broadcast Control Server IPv6 address' field in octets; variable. 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_BCMCS_SERVER_A | option-length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | @@ -283,33 +281,33 @@ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Broadcast Control server-2 address (IPv6 address) | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -5. Consideration for Client Operation for DHCPv6 +4.5 Consideration for Client Operation - A client MAY request either or both of the Broadcast Service - Controller Domain Name List and the IPv6 Address options in the - Options Request Option (ORO) as described in [RFC3315]. + For DHCPv6, a client MAY request either or both of the Broadcast + Service Controller Domain Name List and the IPv6 Address options in + the Options Request Option (ORO) as described in [RFC3315]. If a client receives both the Broadcast Service Controller Domain Name List and IPv6 Address options, it SHOULD use the Domain Name List option. In this case, the client MAY use the Broadcast Service - Controller IPv6 Address option only if, no server in the Broadcast - Service Controller Domain Name List can be resolved or reached. + Controller IPv6 Address option only if the servers in the Broadcast + Service Controller Domain Name List can not be resolved or reached. -6. Consideration for Server Operation +4.6 Consideration for Server Operation A server MAY send a client either the Broadcast Service Controller Domain Name List Option or the Broadcast Service Controller IPv6 Address/IPv4 Address options if the server is configured to do so. In case of DHCPv6, If a client requests both options and the server is configured with both types of information, the server MAY send the client only one of these options if it is configured to do so. In this case the server SHOULD send the Broadcast Service Controller Domain Name List option. @@ -328,90 +326,106 @@ The following table summarizes the server's response for DHCPv6: Client sends in ORO Domain Name List IPv6 Address List __________________________________________________________________ Neither option SHOULD MAY Domain Name List MUST MAY IPv6 Address MAY MUST Both options SHOULD MAY -7. Security Considerations +5. Security Considerations - The security considerations in the base DHCP specs [RFC2131] and - [RFC3315] apply. An attacker may change information of the Broadcast - Service Controller in packets that are in-tranist from DHCP server to - the MN, if integrity protection is not in place. In that event, the - user of the Broadcast service may be diverted to a rogue broadcast - service controller. In the absence of a mutual authentication - procedure between MN and the Broadcast controller, the MN may receive - wrong or fraudulent information about Broadcast Service. + The security considerations in the base DHCP spec [RFC2131] applies. + An attacker may change information of the Broadcast Service + Controller in packets that are in-tranist from DHCP server to the MN, + if integrity protection is not in place. In that event, the user of + the Broadcast service may be diverted to a rogue broadcast service + controller. In the absence of a mutual authentication procedure + between MN and the Broadcast controller, the MN may receive wrong or + fraudulent information about Broadcast Service. -8. IANA Considerations +6. IANA Considerations - The option code for Broadcast Service Controller options MUST be - assigned by IANA. + The following option codes for Broadcast Service Controller option + must be assigned by IANA: -9. Acknowledgements + 1. Broadcast Service Controller Domain Name list (section 4.1) + + 2. OPTION_BCMCS_SERVER_D (section 4.2) + + 3. Broadcast Service Controller IPv4 address option (section 4.3) + + 4. OPTION_BCMCS_SERVER_A (section 4.4) + + The DHCP options should be registered in + http://www.iana.org/assignments/bootp-dhcp-extensions + + The DHCPv6 options should be registered in + http://www.iana.org/assignments/dhcpv6-parameters + +7. Acknowledgements Thanks to the following indivduals for their review and constructive comments during the development of this document: AC Mahendran, Jun Wang, Raymond Hsu, Jayshree Bharatia, Ralph Droms, - Ted Lemon, Bernie Volz. + Ted Lemon, and Margaret Wasserman. -10 Normative References +8. Normative References - [BCMCS] 3GPP2, www.3gpp2.org, "X.S0022, Broadcast and Multicast - Service in cdma2000 Wireless IP Network.", February 2005. + [BCMCS] 3GPP2, www.3gpp2.org, + ftp://ftp.3gpp2.org/TSGX/Projects/X.P0022 2ndV&V.zip, + "X.S0022, Broadcast and Multicast Service in cdma2000 + Wireless IP Network. (work in progress)", December 2004. [RFC1035] Mockapetris, P., "Domain names - implementation and specification", STD 13, RFC 1035, November 1987. - [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC - 2131, 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. + [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. [RFC3396] Lemon, T. and S. Cheshire, "Encoding Long Options in the Dynamic Host Configuration Protocol (DHCPv4)", RFC 3396, November 2002. Authors' Addresses Kuntal Chowdhury Starent Networks 30 International Place Tewksbury, MA 01876 US Phone: +1 214-550-1416 - EMail: kchowdhury@starentnetworks.com - + Email: kchowdhury@starentnetworks.com Parviz Yegani Cisco Systems 3625 Cisco Way San Jose, CA 95134 US Phone: +1 408-832-5729 - EMail: pyegani@cisco.com + Email: pyegani@cisco.com + Lila Madour Ericsson 8400, Decarie Blvd Town of Mount Royal, Quebec H4P 2N2 CANADA Phone: +1 514-345-7900 - EMail: Lila.Madour@ericsson.com + Email: Lila.Madour@ericsson.com Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. 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