draft-ietf-ipv6-ra-mo-flags-00.txt   draft-ietf-ipv6-ra-mo-flags-01.txt 
Network Working Group S. Park, Ed. Network Working Group S. Park, Ed.
Internet-Draft Samsung Electronics Internet-Draft SAMSUNG Electronics
Expires: May 15, 2005 S. Madanapalli Expires: September 24, 2005 S. Madanapalli
Samsung ISO Samsung ISO
T. Jinmei T. Jinmei
Toshiba Toshiba
November 16, 2004 March 26, 2005
Considerations on M and O Flags of IPv6 Router Advertisement Considerations on M and O Flags of IPv6 Router Advertisement
draft-ietf-ipv6-ra-mo-flags-00.txt draft-ietf-ipv6-ra-mo-flags-01.txt
Status of this Memo Status of this Memo
This document is an Internet-Draft and is subject to all provisions By submitting this Internet-Draft, I certify that any applicable
of section 3 of RFC 3667. By submitting this Internet-Draft, each patent or other IPR claims of which I am aware have been disclosed,
author represents that any applicable patent or other IPR claims of and any of which I become aware will be disclosed, in accordance with
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. RFC 3668.
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Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2004). Copyright (C) The Internet Society (2005). All Rights Reserved.
Abstract Abstract
This document clarifies the processing and behaviour of a host for This document clarifies the processing and behaviour of a host for
the M and O flags of IPv6 Router Advertisement and proposes a the M and O flags of IPv6 Router Advertisement and proposes a
solution for invoking the DHCPv6 service based on administrator solution for invoking the DHCPv6 service based on administrator
policy in conjunction with new host variables for the M and O flags. policy in conjunction with new host variables for the M and O flags.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Background . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 4
5. IPv6 Host Variables . . . . . . . . . . . . . . . . . . . . . 4
6. DHCPv6 Policy Variables . . . . . . . . . . . . . . . . . . . 5
6.1 Dependency Between the Configuraton Behaviours . . . . . . 5
6.2 M-Policy . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.3 O-Policy . . . . . . . . . . . . . . . . . . . . . . . . . 6
7. Host Behaviour . . . . . . . . . . . . . . . . . . . . . . . . 7
8. Other Issues on State Transition of M-Flag and O-Flag . . . . 8
9. Router Advertisement Unavailability . . . . . . . . . . . . . 8
10. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . 8
11. An Open Issue: Default Policy Values . . . . . . . . . . . . 9
12. Security Considerations . . . . . . . . . . . . . . . . . . 9
13. IANA Considerations . . . . . . . . . . . . . . . . . . . . 9
14. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
15. Appendix A: Handling of M and O flags from multiple
routers . . . . . . . . . . . . . . . . . . . . . . . . . . 10
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
16.1 Normative References . . . . . . . . . . . . . . . . . . . . 10
16.2 Informative References . . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 11
Intellectual Property and Copyright Statements . . . . . . . . 13
1. Introduction 1. Introduction
To configure a host with network information such as an IP address, To configure a host with network information such as an IP address,
DNS server addresses and other configuration information, several DNS server addresses and other configuration information, several
mechanisms are proposed in the IETF. In particular, IPv6 stateless mechanisms are proposed in the IETF. In particular, IPv6 stateless
address autoconfiguration [RFC2462] and Dynamic Host Configuration address autoconfiguration [RFC2462] and Dynamic Host Configuration
Protocol [RFC3315][RFC3736] will be widely used for configuring the Protocol [RFC3315][RFC3736] will be widely used for configuring the
network information. network information.
This document proposes two conceptual variables, called DHCPv6 Policy This document proposes two conceptual variables, called DHCPv6 Policy
variables corresponding to the M and O flags of Router Advertisement. variables corresponding to the M and O flags of Router Advertisement.
The values of these policy variables in conjuction with the values of The values of these policy variables in conjuction with the values of
the flags of Router Advertisement decide the host behaviour to invoke the flags of Router Advertisement decide the host behaviour to invoke
DHCPv6 services. These policy variables are controlled by the DHCPv6 services. These policy variables are controlled by the
administrator under a certain level of requirement. administrator under a certain level of requirement.
2. Background 2. Background
This section explains why this document appears in the IETF. This section explains why this document appears in the IETF.
Currently, IPv6 WG is trying to make both [RFC2461] and [RFC2462] So far, IPv6 WG has being tried to make both [RFC2461] and [RFC2462]
mature for the Draft Standard but the detailed consideration of the M mature for the Draft Standard. While updating, the text regarding
and O flags of IPv6 Router Advertisement remains beyond scope of the the M and O flags were removed from [I-D.ietf-ipv6-rfc2462bis]
basic documents as described in [I-D.ietf-ipv6-rfc2462bis]. considering the maturity of implementations and operational
experiences.
[I-D.ietf-ipv6-2461bis] says: [I-D.ietf-ipv6-2461bis] says:
o M : o M :
1-bit "Managed address configuration" flag. When set, it 1-bit "Managed address configuration" flag. When set, it
indicates that Dynamic Host Configuration Protocol [DHCPv6] is indicates that Dynamic Host Configuration Protocol [DHCPv6] is
available for address configuration in addition to any addresses available for address configuration in addition to any addresses
autoconfigured using stateless address autoconfiguration. The use autoconfigured using stateless address autoconfiguration. The use
of this flag is further described in [ADDRCONF]. of this flag is further described in [ADDRCONF].
o O : o O :
1-bit "Other stateful configuration" flag. When set, it indicates 1-bit "Other configuration" flag. When set, it indicates that
that [DHCPv6-lite] is available for autoconfiguration of other [DHCPv6lite] is available for autoconfiguration of other
(non-address) information. Examples of such information are DNS- (non-address) information. Examples of such information are
related information or information on other servers within the DNS-related information or information on other servers within the
network. The use of this flag for add is further described in network.
[ADDRCONF].
[Note: "for add" in the last sentence is probably a misspelling.]
[I-D.ietf-ipv6-rfc2462bis] says:
o The details of how a host may use the M flag, including any use of
the "on" and "off" transitions for this flag, to control the use
of the stateful protocol for address assignment will be described
in a separate document. Similarly, the details of how a host may
use the O flag, including any use of the "on" and "off"
transitions for this flag, to control the use of the stateful
protocol for getting other configuration information will be
described in a separate document.
In particular, both "ManagedFlag" and "OtherConfigFlag" which were In particular, both "ManagedFlag" and "OtherConfigFlag" which were
implementation-internal variables were removed during the implementation-internal variables were also removed during the
[I-D.ietf-ipv6-rfc2462bis] work based on the WG consensus with [I-D.ietf-ipv6-rfc2462bis] work based on the WG consensus with
ambiguous operational experiences, and thus new variables (or similar ambiguous operational experiences, and thus new variables (or similar
approaches) are required to treat the M and O flags of IPv6 Router approaches) are required to treat the M and O flags of IPv6 Router
Advertisement on the host. Advertisement on the host.
3. Terminology 3. Terminology
o Host Configuration Behaviour : o Host Configuration Behaviour :
A host can use DHCPv6 for address autoconfiguration as well as A host can use DHCPv6 for address autoconfiguration as well as
other configuration information via other configuration information via Solicit/Advertise/Request/
Solicit/Advertise/Request/Reply message exchanges or Solicit/Reply Reply message exchanges or Solicit/Reply message exchanges (if
message exchanges (if rapid commit is enabled) as described in rapid commit is enabled) as described in [RFC3315]. In this
[RFC3315]. In this document, this term is used for host document, this term is used for host configuration including
configuration including address and other configuration address and other configuration information in conjunction with
information in conjunction with the M flag. the M flag.
o Information Configuration Behaviour : o Information Configuration Behaviour :
A host can use DHCPv6 to obtain configuration information A host can use DHCPv6 to obtain configuration information
parameters excluding addresses. For this operation, parameters excluding addresses. For this operation,
Information-request and Reply messages are used, also as described Information-request and Reply messages are used, also as described
in [RFC3315]. In this document, this term is used for other in [RFC3315]. In this document, this term is used for other
configuration information excluding addresses in conjunction with configuration information excluding addresses in conjunction with
the O flag. the O flag.
skipping to change at page 9, line 28 skipping to change at page 10, line 15
14. Acknowledgements 14. Acknowledgements
The approach of this document was from the RFC2461/RFC2462, so the The approach of this document was from the RFC2461/RFC2462, so the
authors would appreciate the authors of these RFCs and the editors of authors would appreciate the authors of these RFCs and the editors of
RFC2461bis/RFC2462bis. Also, many thanks go to IPv6 Working Group RFC2461bis/RFC2462bis. Also, many thanks go to IPv6 Working Group
members for their valuable discussion on this thread in the mailing members for their valuable discussion on this thread in the mailing
list. Especially to: Greg Daley, Pekka Savola, Ralph Droms, and Stig list. Especially to: Greg Daley, Pekka Savola, Ralph Droms, and Stig
Venaas. Thanks to Bernie Volz of Cisco for his lots of valuable work Venaas. Thanks to Bernie Volz of Cisco for his lots of valuable work
on this document. Special thanks to Radakrishnan and OLN Rao of on this document. Special thanks to Radakrishnan and OLN Rao of
Samsung India Software Operations for their inputs from Samsung India Software Operations for their inputs from
implementation perspective. implementation perspective. Thanks to Noh-Byung Park and Youngkeun
Kim for their supports on this work.
Alain Durand of Sun Microsystems indicated an attack changing the M Alain Durand indicated an attack changing the M and O flags with a
and O flags with a rogue DHCPv6 server and kindly introduced a log rogue DHCPv6 server and kindly introduced a log message as an
message as an effective method to detect a suspicious operation. effective method to detect a suspicious operation.
15. Appendix A: Handling of M and O flags from multiple routers 15. Appendix A: Handling of M and O flags from multiple routers
This document does not take a hard stance on what happens when a host This document does not take a hard stance on what happens when a host
has multiple routers and inconsistent information (different M and O has multiple routers and inconsistent information (different M and O
flags configuration) is learned from different routers. The basic flags configuration) is learned from different routers. The basic
documents [RFC2461]/[RFC2462] already described "Configuration documents [RFC2461]/[RFC2462] already described "Configuration
Consistency" and a host will simply handle inconsistent M and O flags Consistency" and a host will simply handle inconsistent M and O flags
of Router Advertisement in the same manner. of Router Advertisement in the same manner.
skipping to change at page 10, line 14 skipping to change at page 10, line 51
consistency among Router Advertisement parameters from multiple consistency among Router Advertisement parameters from multiple
routers in the same single link as described in Section 5.6 of routers in the same single link as described in Section 5.6 of
[RFC2462]. The authors thus remain "Handling of M and O flags from [RFC2462]. The authors thus remain "Handling of M and O flags from
multiple routers" out of scope of this document. multiple routers" out of scope of this document.
16. References 16. References
16.1 Normative References 16.1 Normative References
[I-D.ietf-ipv6-2461bis] [I-D.ietf-ipv6-2461bis]
"Neighbor Discovery for IP version 6 (IPv6)", Narten, T., "Neighbor Discovery for IP version 6 (IPv6)",
draft-ietf-ipv6-2461bis-00 (work in progress), July 2004. draft-ietf-ipv6-2461bis-02 (work in progress), February
2005.
[I-D.ietf-ipv6-rfc2462bis] [I-D.ietf-ipv6-rfc2462bis]
Thomson, S., "IPv6 Stateless Address Autoconfiguration", Thomson, S., "IPv6 Stateless Address Autoconfiguration",
draft-ietf-ipv6-rfc2462bis-06 (work in progress), draft-ietf-ipv6-rfc2462bis-07 (work in progress), December
September 2004. 2004.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2461] Narten, T., Nordmark, E. and W. Simpson, "Neighbor [RFC2461] Narten, T., Nordmark, E. and W. Simpson, "Neighbor
Discovery for IP Version 6 (IPv6)", RFC 2461, December Discovery for IP Version 6 (IPv6)", RFC 2461, December
1998. 1998.
[RFC2462] Thomson, S. and T. Narten, "IPv6 Stateless Address [RFC2462] Thomson, S. and T. Narten, "IPv6 Stateless Address
Autoconfiguration", RFC 2462, December 1998. Autoconfiguration", RFC 2462, December 1998.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C. and [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C. and

M. Carney, "Dynamic Host Configuration Protocol for IPv6 M. Carney, "Dynamic Host Configuration Protocol for IPv6
(DHCPv6)", RFC 3315, July 2003. (DHCPv6)", RFC 3315, July 2003.
[RFC3736] Droms, R., "Stateless Dynamic Host Configuration Protocol [RFC3736] Droms, R., "Stateless Dynamic Host Configuration Protocol
(DHCP) Service for IPv6", RFC 3736, April 2004. (DHCP) Service for IPv6", RFC 3736, April 2004.
16.2 Informative References 16.2 Informative References
[I-D.ietf-ipv6-node-requirements] [I-D.ietf-ipv6-node-requirements]
Loughney, J., "IPv6 Node Requirements", Loughney, J., "IPv6 Node Requirements",
skipping to change at page 11, line 8 skipping to change at page 11, line 43
August 2004. August 2004.
[I-D.ietf-send-ndopt] [I-D.ietf-send-ndopt]
Arkko, J., Kempf, J., Sommerfeld, B., Zill, B. and P. Arkko, J., Kempf, J., Sommerfeld, B., Zill, B. and P.
Nikander, "SEcure Neighbor Discovery (SEND)", Nikander, "SEcure Neighbor Discovery (SEND)",
draft-ietf-send-ndopt-06 (work in progress), July 2004. draft-ietf-send-ndopt-06 (work in progress), July 2004.
Authors' Addresses Authors' Addresses
Soohong Daniel Park, Ed. Soohong Daniel Park, Ed.
Samsung Electronics Mobile Platform Laboratory, SAMSNUG Electronics
416 Maetan-3dong, Yeongtong-gu 416 Maetan-3dong, Yeongtong-Gu
Suwon-si, Gyeonggi-do 442-742 Suwon, Gyeonggi-Do 443-742
KOREA KOREA
Phone: +82 31 200 4508 Phone: +82 31 200 4508
EMail: soohong.park@samsung.com EMail: soohong.park@samsung.com
Syam Madanapalli Syam Madanapalli
Samsung India Software Operation Samsung India Software Operation
J.P. Techno Park, 3/1 J.P. Techno Park, 3/1
Millers Road, Bangalore 560-052 Millers Road, Bangalore 560-052
INDIA INDIA
Phone: +91 80 51197777 Phone: +91 80 51197777
EMail: syam@samsung.com EMail: syam@samsung.com
Tatuya Jinmei Tatuya Jinmei
skipping to change at page 12, line 41 skipping to change at page 13, line 41
This document and the information contained herein are provided on an This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Copyright Statement Copyright Statement
Copyright (C) The Internet Society (2004). This document is subject Copyright (C) The Internet Society (2005). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights. except as set forth therein, the authors retain all their rights.
Acknowledgment Acknowledgment
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is currently provided by the
Internet Society. Internet Society.
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