Network Working Group K. Chowdhury
Internet-Draft Starent Networks
Expires: June 27, 2005 P. Yegani
Cisco Systems
L. Madour
Ericsson
December 27, 2004
DHCPv6 Options for Broadcast and Multicast Control Servers
draft-ietf-dhc-bcmcv6-option-00.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.
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.
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 June 27, 2005.
Copyright Notice
Copyright (C) The Internet Society (2004).
Abstract
This document defines new options for Broadcast and Multicast Service
controller discovery in an IP network. Broadcast and Multicast
service over 3G wireless networks are being developed at the time of
writing this document. Users of this service interact with a
Chowdhury, et al. Expires June 27, 2005 [Page 1]
Internet-Draft December 2004
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 IPv6 addresses in the user's
devices. 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 . . . 6
4.2 Broadcast Service Controller IPv6 address option . . . . . 6
5. Consideration for Client Operation . . . . . . . . . . . . . . 8
6. Consideration for Server Operation . . . . . . . . . . . . . . 9
7. Security Considerations . . . . . . . . . . . . . . . . . . . 10
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
10. Normative References . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 12
Intellectual Property and Copyright Statements . . . . . . . . 14
Chowdhury, et al. Expires June 27, 2005 [Page 2]
Internet-Draft December 2004
1. Motivation
Dynamic Host Configuration Protocol [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.
DHCP is being used in 3GPP2, for example, to assist with the
discovery of the BCMCS Controller in a mobile operators IP network.
The BCMCS includes a controller component that is responsible for
managing the service via interaction with the users 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 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 IPv6 address becomes unrealistic. Therefore, DHCPv6
[RFC3315] is considered to be a method to dynamically configure
controller IPv6 address in the user's devices in the 3G wireless
networks. DHCPv6 can also be used to convey the fully qualified
domain name of the broadcast service controller to the user. The
user in turn makes DNS queries to obtain the IPv6 address of the
associated broadcast service controller.
In order to allow the users to discover the broadcast controllers,
the clients need to request for appropriate option codes from the
DHCPv6 servers using Option-Request-Option and the DHCPv6 servers
need to return corresponding configuration options that carry the
broadcast and multicast service controller IPv6 address and/or Domain
Name list. The motivation for this document is to define the
necessary options and option codes.
Chowdhury, et al. Expires June 27, 2005 [Page 3]
Internet-Draft December 2004
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:
+------------+ +--------+
| | | |
| Controller | | DHCPv6 |
| | | 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
network. The network elements except MN/user and the DHCPv6 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].
Chowdhury, et al. Expires June 27, 2005 [Page 4]
Internet-Draft December 2004
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.
Chowdhury, et al. Expires June 27, 2005 [Page 5]
Internet-Draft December 2004
4. Broadcast Service Controller Options
This section defines the configuration options for the controller of
Broadcast Service. The options in the document are specified similar
to [RFC3319].
4.1 Broadcast Service Controller Domain Name List option
The option length is followed by a sequence of labels, encoded
according to Section 3.1 of RFC 1035 [5].
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-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 |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.2 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.
Chowdhury, et al. Expires June 27, 2005 [Page 6]
Internet-Draft December 2004
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Broadcast Control server-1 address (IPv6 address) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Broadcast Control server-2 address (IPv6 address) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Chowdhury, et al. Expires June 27, 2005 [Page 7]
Internet-Draft December 2004
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].
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.
Chowdhury, et al. Expires June 27, 2005 [Page 8]
Internet-Draft December 2004
6. Consideration for Server Operation
A server MAY send a client one or both of the Broadcast Service
Controller Domain Name List and Broadcast Service Controller IPv6
Address options if the server is configured to do so.
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.
A server configured with the Broadcast Service Controller IPv6
Address information MUST send a client the Broadcast Service
Controller IPv6 Address option if that client requested only the
Broadcast Service Controller IPv6 address option and not the
Broadcast Service Controller Domain Name List option in the ORO
(RFC3315]).
If a client requests for the Broadcast Service Controller IPv6 option
and the Server is configured only with the Domain Names, the Server
MUST return the Domain Names List and vice versa.
The following table summarizes the server's response:
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
Chowdhury, et al. Expires June 27, 2005 [Page 9]
Internet-Draft December 2004
7. Security Considerations
The security considerations in the base DHCPv6 spec [RFC3315]
applies. An attacker may change information of the Broadcast Service
Controller in packets that are in-tranist from DHCPv6 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.
Chowdhury, et al. Expires June 27, 2005 [Page 10]
Internet-Draft December 2004
8. IANA Considerations
The option codes OPTION_BCMCS_SERVER_A, OPTION_BCMCS_SERVER_D for
Broadcast Service Controller Domain Name list and IPv6 address
respectively Must be assigned by IANA.
Chowdhury, et al. Expires June 27, 2005 [Page 11]
Internet-Draft December 2004
9. 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,
Bernie Volz.
10 Normative References
[BCMCS] 3GPP2, www.3gpp2.org, "X.S0022, Broadcast and Multicast
Service in cdma2000 Wireless IP Network.", February 2005.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[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.
[RFC3319] Schulzrinne, H. and B. Volz, "Dynamic Host Configuration
Protocol (DHCPv6) Options for Session Initiation Protocol
(SIP) Servers", RFC 3319, July 2003.
Authors' Addresses
Kuntal Chowdhury
Starent Networks
2540 Coolwater Dr.
Plano, TX 75025
US
Phone: +1 214-550-1416
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
Chowdhury, et al. Expires June 27, 2005 [Page 12]
Internet-Draft December 2004
Lila Madour
Ericsson
8400, Decarie Blvd
Town of Mount Royal, Quebec H4P 2N2
CANADA
Phone: +1 514-345-7900
EMail: Lila.Madour@ericsson.com
Chowdhury, et al. Expires June 27, 2005 [Page 13]
Internet-Draft December 2004
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. Information
on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at
ietf-ipr@ietf.org.
Disclaimer of Validity
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Copyright Statement
Copyright (C) The Internet Society (2004). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
Acknowledgment
Funding for the RFC Editor function is currently provided by the
Internet Society.
Chowdhury, et al. Expires June 27, 2005 [Page 14]
