draft-ietf-ipsecme-ikev2-redirect-00.txt   draft-ietf-ipsecme-ikev2-redirect-01.txt 
Network Working Group V. Devarapalli Network Working Group V. Devarapalli
Internet-Draft WiChorus Internet-Draft WiChorus
Intended status: Standards Track K. Weniger Intended status: Standards Track K. Weniger
Expires: April 23, 2009 Panasonic Expires: May 7, 2009 Panasonic
October 20, 2008 November 3, 2008
Re-direct Mechanism for IKEv2 Re-direct Mechanism for IKEv2
draft-ietf-ipsecme-ikev2-redirect-00.txt draft-ietf-ipsecme-ikev2-redirect-01.txt
Status of this Memo Status of this Memo
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This Internet-Draft will expire on April 23, 2009. This Internet-Draft will expire on May 7, 2009.
Abstract Abstract
IKEv2 is a popular protocol for setting up VPN tunnels from a remote IKEv2 is a popular protocol for setting up VPN tunnels from a remote
location to a gateway so that the VPN client can access services in location to a gateway so that the VPN client can access services in
the network behind the gateway. Currently there is no standard the network behind the gateway. Currently there is no standard
mechanism specified that allows an overloaded VPN gateway to re- mechanism specified that allows an overloaded VPN gateway to re-
direct the VPN client to attach to another gateway. This document direct the VPN client to attach to another gateway. This document
proposes a re-direct mechanism for IKEv2. The proposed mechanism can proposes a re-direct mechanism for IKEv2. The proposed mechanism can
also be used for Mobile IPv6 to enable the home agent to re-direct also be used for Mobile IPv6 to enable the home agent to re-direct
the mobile node to another home agent. the mobile node to another home agent.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. IKEv2 Exchange with Redirect . . . . . . . . . . . . . . . . . 4 3. IKEv2 Exchange with Redirect . . . . . . . . . . . . . . . . . 4
4. Use of Anycast Addresses with the Re-direct Mechanism . . . . 5 4. Use of Anycast Addresses with the Re-direct Mechanism . . . . 5
5. Redirect Messages . . . . . . . . . . . . . . . . . . . . . . 6 5. Gateway Initiated Redirect . . . . . . . . . . . . . . . . . . 6
5.1. REDIRECT_SUPPORTED . . . . . . . . . . . . . . . . . . . . 6 6. Redirect Messages . . . . . . . . . . . . . . . . . . . . . . 7
5.2. REDIRECT . . . . . . . . . . . . . . . . . . . . . . . . . 7 6.1. REDIRECT_SUPPORTED . . . . . . . . . . . . . . . . . . . . 7
5.3. REDIRECTED_FROM . . . . . . . . . . . . . . . . . . . . . 7 6.2. REDIRECT . . . . . . . . . . . . . . . . . . . . . . . . . 7
6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 6.3. REDIRECTED_FROM . . . . . . . . . . . . . . . . . . . . . 8
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 6.4. REDIRECT_ACK . . . . . . . . . . . . . . . . . . . . . . . 9
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
9.1. Normative References . . . . . . . . . . . . . . . . . . . 9 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
9.2. Informative References . . . . . . . . . . . . . . . . . . 10 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 10 10.1. Normative References . . . . . . . . . . . . . . . . . . . 10
Intellectual Property and Copyright Statements . . . . . . . . . . 11 10.2. Informative References . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11
Intellectual Property and Copyright Statements . . . . . . . . . . 12
1. Introduction 1. Introduction
IKEv2 [2] is widely used for setting up IPsec-based VPNs. The IP IKEv2 [2] is widely used for setting up IPsec-based VPNs. The IP
address of the VPN gateway can be configured on the VPN client. But address of the VPN gateway can be configured on the VPN client. But
this does not scale well, when the number of VPN gateways is large. this does not scale well, when the number of VPN gateways is large.
Dynamic discovery of VPN gateways using DNS is quite widely used too. Dynamic discovery of VPN gateways using DNS is quite widely used too.
However, using DNS is not flexible when it comes to assigning a VPN However, using DNS is not flexible when it comes to assigning a VPN
gateway to the VPN client based on the load on the VPN gateways. The gateway to the VPN client based on the load on the VPN gateways. The
VPN client typically tries to connect to the IP address of the VPN VPN client typically tries to connect to the IP address of the VPN
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the IKE_SA_INIT exchange. The re-direct mechanism can also be used the IKE_SA_INIT exchange. The re-direct mechanism can also be used
in conjunction with anycast addresses. In this case, anycast address in conjunction with anycast addresses. In this case, anycast address
for the cluster of VPN gateways is stored in the DNS instead of a for the cluster of VPN gateways is stored in the DNS instead of a
list of unicast IP addresses of the VPN gateways. list of unicast IP addresses of the VPN gateways.
The re-direct can also happen because of administrative or optimal The re-direct can also happen because of administrative or optimal
routing reasons. This document does not attempt to provide an routing reasons. This document does not attempt to provide an
exhaustive list of reasons for re-directing a VPN client to another exhaustive list of reasons for re-directing a VPN client to another
VPN gateway. VPN gateway.
Mobile IPv6 [4] may use IKEv2 for mutual authentication between the Mobile IPv6 [3] may use IKEv2 for mutual authentication between the
mobile node and the home agent. IKEv2 may also be used for home mobile node and the home agent. IKEv2 may also be used for home
address configuration and setting up IPsec security associations for address configuration and setting up IPsec security associations for
protecting Mobile IPv6 signaling messages [5]. The IKEv2 exchange protecting Mobile IPv6 signaling messages [4]. The IKEv2 exchange
precedes the exchange of Mobile IPv6 signaling messages. Therefore precedes the exchange of Mobile IPv6 signaling messages. Therefore
the mechanism described in this document can be also be used by a the mechanism described in this document can be also be used by a
Mobile IPv6 home agent to re-direct a mobile node to another home Mobile IPv6 home agent to re-direct a mobile node to another home
agent. agent.
There is a Home Agent Switch mechanism available for re-directing a There is a Home Agent Switch mechanism available for re-directing a
mobile node to another home agent, described in [6]. The Home Agent mobile node to another home agent, described in [5]. The Home Agent
Switch mechanism can only be used after the binding cache had been Switch mechanism can only be used after the binding cache had been
created at the home agent for the mobile node. The disadvantage with created at the home agent for the mobile node. The disadvantage with
this is that quite a bit of state is created on the home agent before this is that quite a bit of state is created on the home agent before
the mobile node can be re-directed to another home agent. The the mobile node can be re-directed to another home agent. The
mechanism described in this document can be used for re-directing a mechanism described in this document can be used for re-directing a
mobile node before any state is created on the home agent. mobile node before any state related to the Mobile IPv6 binding is
created on the home agent.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [1]. document are to be interpreted as described in [1].
3. IKEv2 Exchange with Redirect 3. IKEv2 Exchange with Redirect
To redirect a IKEv2 session to another VPN gateway, the VPN gateway To redirect a IKEv2 session to another VPN gateway, the VPN gateway
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If the destination address on the IKE_SA_INIT request is an anycast If the destination address on the IKE_SA_INIT request is an anycast
address, the VPN gateway that received the IKE_SA_INIT request MUST address, the VPN gateway that received the IKE_SA_INIT request MUST
include the REDIRECT payload to re-direct the VPN client to a unicast include the REDIRECT payload to re-direct the VPN client to a unicast
address of one of the VPN gateway. The VPN gateway that received the address of one of the VPN gateway. The VPN gateway that received the
IKE_SA_INIT request MAY re-direct the client to its own unicast IKE_SA_INIT request MAY re-direct the client to its own unicast
address, if it is not overloaded. address, if it is not overloaded.
The rest of the IKEv2 exchange is the same as described in Section 3. The rest of the IKEv2 exchange is the same as described in Section 3.
5. Redirect Messages 5. Gateway Initiated Redirect
5.1. REDIRECT_SUPPORTED The re-direct mechanism may also be used by a VPN gateway to re-
direct the client to another VPN gateway in middle of a session. To
re-direct a client, the gateway should send an INFORMATIONAL message
with the REDIRECT Notify payload. The REDIRECT payload MUST carry
information about the new VPN gateway. When the client receives this
message, it MUST send an INFORMATIONAL message with the REDIRECT_ACK
Notify payload. Until the client responds with an INFORMATIONAL
message with the REDIRECT_ACK payload, the gateway SHOULD re-transmit
the re-direct INFORMATIONAL message as described in [2]. The
following illustrates the INFORMATIONAL message exchange for gateway-
initiated redirect.
Initiator (VPN client) Responder (VPN GW)
---------------------- ------------------
<-- HDR, SK {[REDIRECT]}
HDR, SK {[REDIRECT_ACK]} -->
The INFORMATIONAL message exchange described above is protected by
the existing IKEv2 SA between the client and the gateway.
6. Redirect Messages
6.1. REDIRECT_SUPPORTED
The REDIRECT_SUPPORTED payload is included in the initial IKE_SA_INIT The REDIRECT_SUPPORTED payload is included in the initial IKE_SA_INIT
request by the initiator to indicate support for the IKEv2 re-direct request by the initiator to indicate support for the IKEv2 re-direct
mechanism described in this document. mechanism described in this document.
1 2 3 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 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Payload |C| RESERVED | Payload Length | | Next Payload |C| RESERVED | Payload Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol ID | SPI Size (=0) | Notify Message Type | | Protocol ID | SPI Size (=0) | Notify Message Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and
the 'Notify Message Type' fields are the same as described in Section the 'Notify Message Type' fields are the same as described in Section
3.10 of RFC 4306 [3]. The 'SPI Size' field MUST be set to 0 to 3.10 of [2]. The 'SPI Size' field MUST be set to 0 to indicate that
indicate that the SPI is not present in this message. the SPI is not present in this message.
The 'Payload Length' field MUST be set to '8'. The 'Notify Message The 'Payload Length' field MUST be set to '8'. The 'Notify Message
Type' field is set to indicate the REDIRECT_SUPPORTED payload <value Type' field is set to indicate the REDIRECT_SUPPORTED payload <value
to be assigned by IANA>. to be assigned by IANA>.
5.2. REDIRECT 6.2. REDIRECT
The REDIRECT payload is included in an IKE_SA_INIT response from the The REDIRECT payload is included in an IKE_SA_INIT response from the
responder when the responder wants to re-direct the initiator to responder when the responder wants to re-direct the initiator to
another VPN gateway. The message includes the new responder's IP another VPN gateway. The message includes the new responder's IP
address. address.
1 2 3 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 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Payload |C| RESERVED | Payload Length | | Next Payload |C| RESERVED | Payload Length |
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| Protocol ID | SPI Size (=0) | Notify Message Type | | Protocol ID | SPI Size (=0) | Notify Message Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| GW Ident Type | | | GW Ident Type | |
+---------------+ ~ +---------------+ ~
~ New Responder GW Identity ~ ~ New Responder GW Identity ~
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and
the 'Notify Message Type' fields are the same as described in Section the 'Notify Message Type' fields are the same as described in Section
3.10 of RFC 4306 [3]. The 'SPI Size' field MUST be set to 0 to 3.10 of [2]. The 'SPI Size' field MUST be set to 0 to indicate that
indicate that the SPI is not present in this message. the SPI is not present in this message.
The 'Payload Length' field MUST be set to either '13' or '25' If the IP address of the new VPN gateway is sent, the 'Payload
depending on whether an IPv4 or IPv6 address of the new VPN gateway Length' field MUST be set to either '13' or '25' depending on whether
is sent in the message. The 'Notify Message Type' field is set to an IPv4 or IPv6 address is sent in the message. If the FQDN of the
indicate the REDIRECT payload <value to be assigned by IANA>. The new VPN gateway is sent, the 'Payload Length' field is set to the
'GW Identity Type' field indicates the type of information that is length of the FQDN plus the fixed fields in the message. The 'Notify
sent to identify the new VPN gateway. The following values are Message Type' field is set to indicate the REDIRECT payload <value to
reserved by this document. be assigned by IANA>. The 'GW Identity Type' field indicates the
type of information that is sent to identify the new VPN gateway.
The following values are reserved by this document.
1 - IPv4 address of the new VPN gateway 1 - IPv4 address of the new VPN gateway
2 - IPv6 address of the new VPN gateway 2 - IPv6 address of the new VPN gateway
3 - FQDN of the new VPN gateway 3 - FQDN of the new VPN gateway
All other values for this field are reserved and MUST NOT be used. All other values for this field are reserved and MUST NOT be used.
The identity of the new VPN gateway is carried in the 'New Responder The identity of the new VPN gateway is carried in the 'New Responder
GW Identity' field. GW Identity' field.
5.3. REDIRECTED_FROM 6.3. REDIRECTED_FROM
The REDIRECTED_FROM message type is included in the IKE_SA_INIT The REDIRECTED_FROM message type is included in the IKE_SA_INIT
request from the initiator to the new VPN gateway to indicate the IP request from the initiator to the new VPN gateway to indicate the IP
address of the original VPN gateway that re-directed the initiator. address of the original VPN gateway that re-directed the initiator.
The original VPN gateway's IP address is included in the message. The original VPN gateway's IP address is included in the message.
1 2 3 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 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Payload |C| RESERVED | Payload Length | | Next Payload |C| RESERVED | Payload Length |
skipping to change at page 8, line 20 skipping to change at page 8, line 46
| Protocol ID | SPI Size (=0) | Notify Message Type | | Protocol ID | SPI Size (=0) | Notify Message Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| GW Ident Type | | | GW Ident Type | |
+---------------+ ~ +---------------+ ~
~ Original Responder GW Identity ~ ~ Original Responder GW Identity ~
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and
the 'Notify Message Type' fields are the same as described in Section the 'Notify Message Type' fields are the same as described in Section
3.10 of RFC 4306 [3]. The 'SPI Size' field MUST be set to 0 to 3.10 of [2] The 'SPI Size' field MUST be set to 0 to indicate that
indicate that the SPI is not present in this message. the SPI is not present in this message.
The 'Payload Length' field MUST be set to either '13' or '25' The 'Payload Length' field MUST be set to either '13' or '25'
depending on whether an IPv4 or IPv6 address of the original VPN depending on whether an IPv4 or IPv6 address of the original VPN
gateway is sent in the message. The 'Notify Message Type' field is gateway is sent in the message. The 'Notify Message Type' field is
set to indicate the REDIRECTED_FROM payload <value to be assigned by set to indicate the REDIRECTED_FROM payload <value to be assigned by
IANA>. The 'GW Identity Type' field indicates the type of IANA>. The 'GW Identity Type' field indicates the type of
information that is sent to identify the new VPN gateway. The information that is sent to identify the new VPN gateway. The
following values are reserved by this document. following values are reserved by this document.
1 - IPv4 address of the original VPN gateway 1 - IPv4 address of the original VPN gateway
2 - IPv6 address of the original VPN gateway 2 - IPv6 address of the original VPN gateway
All other values for this field are reserved and MUST NOT be used. All other values for this field are reserved and MUST NOT be used.
The identity of the original VPN gateway is carried in the 'Original The identity of the original VPN gateway is carried in the 'Original
Responder GW Identity' field. Responder GW Identity' field.
6. Security Considerations 6.4. REDIRECT_ACK
The REDIRECT_ACK payload is included in the INFORMATIONAL message
sent by the VPN client to the gateway in response to a gateway
initiated redirect message as described in Section 5.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Payload |C| RESERVED | Payload Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol ID | SPI Size (=0) | Notify Message Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The 'Next Payload', 'Payload Length', 'Protocol ID', 'SPI Size' and
the 'Notify Message Type' fields are the same as described in Section
3.10 of [2]. The 'SPI Size' field MUST be set to 0 to indicate that
the SPI is not present in this message.
The 'Payload Length' field MUST be set to '8'. The 'Notify Message
Type' field is set to indicate the REDIRECT_ACK payload <value to be
assigned by IANA>.
7. Security Considerations
An eavesdropper on the path between VPN client and server may send a An eavesdropper on the path between VPN client and server may send a
redirect to the client upon receiving an IKE_SA_INIT message from redirect to the client upon receiving an IKE_SA_INIT message from
this client. This is no problem regarding DoS attacks for the VPN this client. This is no problem regarding DoS attacks for the VPN
connection, since an on-path-attacker can as well drop the connection, since an on-path-attacker can as well drop the
IKE_SA_INIT requests to prevent VPN access for the client. But an IKE_SA_INIT requests to prevent VPN access for the client. But an
eavesdropper on the path between VPN client and server can redirect a eavesdropper on the path between VPN client and server can redirect a
large number of clients to a victim, which is then flooded with large number of clients to a victim, which is then flooded with
IKE_SA_INIT requests. Flooding only happens if many clients initiate IKE_SA_INIT requests. Flooding only happens if many clients initiate
IKEv2 exchange at almost the same time, which is considered a rare IKEv2 exchange at almost the same time, which is considered a rare
event. However, this may happen if a Home Agent/VPN server is event. However, this may happen if a Home Agent/VPN server is
shutdown for maintenance and all clients need to re-establish VPN shutdown for maintenance and all clients need to re-establish VPN
connections with another Home Agent/VPN server or if the on-path connections with another Home Agent/VPN server or if the on-path
attacker forces all IPsec security associations to expire by dropping attacker forces all IPsec security associations to expire by dropping
all received IKEv2 messages. all received IKEv2 messages.
The use of REDIRECTED_FROM payload is intended to discourage a rogue The use of REDIRECTED_FROM payload is intended to discourage a rogue
VPN gateway from re-directing a large number of VPN clients to a VPN gateway from re-directing a large number of VPN clients to a
particular VPN gateway. It does not prevent such a DoS attack. particular VPN gateway. It does not prevent such a DoS attack.
7. IANA Considerations 8. IANA Considerations
This document defines three new IKEv2 Notification Message types as This document defines four new IKEv2 Notification Message types as
described in Section 5. The three Notify Message Types must be described in Section 6. The four Notify Message Types must be
assigned values between 16396 and 40959. assigned values between 16396 and 40959.
o REDIRECT_SUPPORTED o REDIRECT_SUPPORTED
o REDIRECT o REDIRECT
o REDIRECTED_FROM o REDIRECTED_FROM
o REDIRECT_ACK
8. Acknowledgements 9. Acknowledgements
The use of anycast address with IKEv2 was first described in [7]. It The use of anycast address with IKEv2 was first described in [6]. It
was then added to an early draft version of RFC 5026 and later was then added to an early draft version of RFC 5026 and later
removed before the RFC was published. Therefore the authors of [7] removed before the RFC was published. Therefore the authors of [6]
and RFC 5026 are acknowledged. and RFC 5026 are acknowledged.
Thanks to Pasi Eronen, with who, the solution described in this Thanks to Pasi Eronen, with who, the solution described in this
document was extensively discussed. Thanks to Tero Kivinen for document was extensively discussed. Thanks to Tero Kivinen for
suggesting the use of REDIRECTED_FROM payload. The authors would suggesting the use of REDIRECTED_FROM payload. The authors would
also like to thank Yaron Sheffer and Arnaud Ebalard for their reviews also like to thank Yaron Sheffer, Sunil Kumar and Arnaud Ebalard for
and comments. their reviews and comments.
9. References 10. References
9.1. Normative References 10.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[2] Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen, "Internet Key [2] Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen, "Internet Key
Exchange Protocol: IKEv2", draft-ietf-ipsecme-ikev2bis-00 (work Exchange Protocol: IKEv2", draft-ietf-ipsecme-ikev2bis-01 (work
in progress), August 2008. in progress), October 2008.
[3] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", RFC 4306,
December 2005.
9.2. Informative References 10.2. Informative References
[4] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support in [3] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support in
IPv6", RFC 3775, June 2004. IPv6", RFC 3775, June 2004.
[5] Giaretta, G., Kempf, J., and V. Devarapalli, "Mobile IPv6 [4] Giaretta, G., Kempf, J., and V. Devarapalli, "Mobile IPv6
Bootstrapping in Split Scenario", RFC 5026, October 2007. Bootstrapping in Split Scenario", RFC 5026, October 2007.
[6] Haley, B., Devarapalli, V., Deng, H., and J. Kempf, "Mobility [5] Haley, B., Devarapalli, V., Deng, H., and J. Kempf, "Mobility
Header Home Agent Switch Message", RFC 5142, January 2008. Header Home Agent Switch Message", RFC 5142, January 2008.
[7] Weniger, K. and F. Dupont, "IKEv2-based Home Agent Assignment in [6] Weniger, K. and F. Dupont, "IKEv2-based Home Agent Assignment in
Mobile IPv6/NEMO Bootstrapping", draft-dupont-ikev2-haassign-02 Mobile IPv6/NEMO Bootstrapping", draft-dupont-ikev2-haassign-02
(work in progress), January 2007. (work in progress), January 2007.
Authors' Addresses Authors' Addresses
Vijay Devarapalli Vijay Devarapalli
WiChorus WiChorus
3590 North First St 3590 North First St
San Jose, CA 95134 San Jose, CA 95134
USA USA
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