draft-ietf-ipsecme-ipsec-ha-03.txt   draft-ietf-ipsecme-ipsec-ha-04.txt 
Network Working Group Y. Nir Network Working Group Y. Nir
Internet-Draft Check Point Internet-Draft Check Point
Intended status: Informational May 12, 2010 Intended status: Informational June 1, 2010
Expires: November 13, 2010 Expires: December 3, 2010
IPsec High Availability and Load Sharing Problem Statement IPsec High Availability and Load Sharing Problem Statement
draft-ietf-ipsecme-ipsec-ha-03 draft-ietf-ipsecme-ipsec-ha-04
Abstract Abstract
This document describes a requirement from IKE and IPsec to allow for This document describes a requirement from IKE and IPsec to allow for
more scalable and available deployments for VPNs. It defines more scalable and available deployments for VPNs. It defines
terminology for high availability and load sharing clusters terminology for high availability and load sharing clusters
implementing IKE and IPsec, and describes gaps in the existing implementing IKE and IPsec, and describes gaps in the existing
standards. standards.
Status of this Memo Status of this Memo
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 13, 2010. This Internet-Draft will expire on December 3, 2010.
Copyright Notice Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Provisions Relating to IETF Documents Provisions Relating to IETF Documents
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include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions Used in This Document . . . . . . . . . . . . 3 1.1. Conventions Used in This Document . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. The Problem Statement . . . . . . . . . . . . . . . . . . . . 5 3. The Problem Statement . . . . . . . . . . . . . . . . . . . . 5
3.1. Lots of Long Lived State . . . . . . . . . . . . . . . . . 5 3.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2. IKE Counters . . . . . . . . . . . . . . . . . . . . . . . 5 3.2. Lots of Long Lived State . . . . . . . . . . . . . . . . . 5
3.3. Outbound SA Counters . . . . . . . . . . . . . . . . . . . 6 3.3. IKE Counters . . . . . . . . . . . . . . . . . . . . . . . 6
3.4. Inbound SA Counters . . . . . . . . . . . . . . . . . . . 6 3.4. Outbound SA Counters . . . . . . . . . . . . . . . . . . . 6
3.5. Missing Synch Messages . . . . . . . . . . . . . . . . . . 7 3.5. Inbound SA Counters . . . . . . . . . . . . . . . . . . . 7
3.6. Simultaneous use of IKE and IPsec SAs by Different 3.6. Missing Synch Messages . . . . . . . . . . . . . . . . . . 7
Members . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.7. Simultaneous use of IKE and IPsec SAs by Different
3.6.1. Outbound SAs using counter modes . . . . . . . . . . . 8 Members . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.7. Different IP addresses for IKE and IPsec . . . . . . . . . 9 3.7.1. Outbound SAs using counter modes . . . . . . . . . . . 9
4. Security Considerations . . . . . . . . . . . . . . . . . . . 9 3.8. Different IP addresses for IKE and IPsec . . . . . . . . . 9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 3.9. Allocation of SPIs . . . . . . . . . . . . . . . . . . . . 9
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 4. Security Considerations . . . . . . . . . . . . . . . . . . . 10
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
7. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8. Informative References . . . . . . . . . . . . . . . . . . . . 10 8. Informative References . . . . . . . . . . . . . . . . . . . . 11
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 11 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
IKEv2, as described in [RFC4306] and [RFC4718], and IPsec, as IKEv2, as described in [RFC4306] and [IKEv2bis], and IPsec, as
described in [RFC4301] and others, allows deployment of VPNs between described in [RFC4301] and others, allows deployment of VPNs between
different sites as well as from VPN clients to protected networks. different sites as well as from VPN clients to protected networks.
As VPNs become increasingly important to the organizations deploying As VPNs become increasingly important to the organizations deploying
them, there is a demand to make IPsec solutions more scalable and them, there is a demand to make IPsec solutions more scalable and
less prone to down time, by using more than one physical gateway to less prone to down time, by using more than one physical gateway to
either share the load or back each other up. Similar demands have either share the load or back each other up. Similar demands have
been made in the past for other critical pieces of an organizations's been made in the past for other critical pieces of an organizations's
infrastructure, such as DHCP and DNS servers, web servers, databases infrastructure, such as DHCP and DNS servers, web servers, databases
and others. and others.
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bys". [VRRP] is one method of building such a cluster. bys". [VRRP] is one method of building such a cluster.
"Load Sharing Cluster", or "LS Cluster" is a cluster where more than "Load Sharing Cluster", or "LS Cluster" is a cluster where more than
one of the members may be active at the same time. The term "load one of the members may be active at the same time. The term "load
balancing" is also common, but it implies that the load is actually balancing" is also common, but it implies that the load is actually
balanced between the members, and we don't want to even imply that balanced between the members, and we don't want to even imply that
this is a requirement. this is a requirement.
"Failover" is the event where a one member takes over some load from "Failover" is the event where a one member takes over some load from
some other member. In a hot standby cluster, this hapens when a some other member. In a hot standby cluster, this hapens when a
standby memeber becomes active due to a failure of the former active standby member becomes active due to a failure of the former active
member, or because of an administrator command. In a load sharing member, or because of an administrator command. In a load sharing
cluster this usually happens because of a failure of one of the cluster this usually happens because of a failure of one of the
members, but certain load-balancing technologies may allow a members, but certain load-balancing technologies may allow a
particular load (such as all the flows associated with a particular particular load (such as all the flows associated with a particular
child SA) to move from one member to another to even out the load, child SA) to move from one member to another to even out the load,
even without any failures. even without any failures.
"Tight Cluster" is a cluster where all the members share an IP "Tight Cluster" is a cluster where all the members share an IP
address. This could be accomplished using configured interfaces with address. This could be accomplished using configured interfaces with
specialized protocols or hardware, such as VRRP, or through the use specialized protocols or hardware, such as VRRP, or through the use
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"Synch Channel" is a communications channel among the cluster "Synch Channel" is a communications channel among the cluster
members, used to transfer state information. The synch channel may members, used to transfer state information. The synch channel may
or may not be IP based, may or may not be encrypted, and may work or may not be IP based, may or may not be encrypted, and may work
over short or long distances. The security and physical over short or long distances. The security and physical
characteristics of this channel are out of scope for this document, characteristics of this channel are out of scope for this document,
but it is a requirement that its use be minimized for scalability. but it is a requirement that its use be minimized for scalability.
3. The Problem Statement 3. The Problem Statement
This section starts by scoping the problem, and goes on to list each
of the issues encountered while setting up a cluster of IPsec VPN
gateways.
3.1. Scope
This document will make no attempt to describe the problems in This document will make no attempt to describe the problems in
setting up a cluster. The following subsections describe the setting up a generic cluster. It describes only problems related to
problems related to the protocol itself. the IKE/IPsec protocols.
We also ignore the problem of synchronizing the policy between The problem of synchronizing the policy between cluster members is
cluster members, as this is an administrative issue that is not out of scope, as this is an administrative issue that is not
particular to either clusters or to IPsec. particular to either clusters or to IPsec.
Note that the interesting scenario here is VPN, whether tunneled The interesting scenario here is VPN, whether tunneled site-to-site
site-to-site or remote access. host-to-host transport mode is not or remote access. Host-to-host transport mode is not expected to
expected to benefit from this work. benefit from this work.
3.1. Lots of Long Lived State We do not describe in full the problems of the communication channel
between cluster members (the Synch Channel), nor do we intend to
specify anything in this space later. Specifically, mixed-vendor
clusters are out of scope.
The problem statement anticipates possible protocol-level solutions
between IKE/IPsec peers, in order to improve the availability and/or
performance of VPN clusters. One vendor's IPsec endpoint should be
able to work, optimally, with another vendor's cluster.
3.2. Lots of Long Lived State
IKE and IPsec have a lot of long lived state: IKE and IPsec have a lot of long lived state:
o IKE SAs last for minutes, hours, or days, and carry keys and other o IKE SAs last for minutes, hours, or days, and carry keys and other
information. Some gateways may carry thousands to hundreds of information. Some gateways may carry thousands to hundreds of
thousands of IKE SAs. thousands of IKE SAs.
o IPsec SAs last for minutes or hours, and carry keys, selectors and o IPsec SAs last for minutes or hours, and carry keys, selectors and
other information. Some gateways may carry hundreds of thousands other information. Some gateways may carry hundreds of thousands
such IPsec SAs. such IPsec SAs.
o SPD Cache entries. While the SPD is unchanging, the SPD cache o SPD Cache entries. While the SPD is unchanging, the SPD cache
changes on the fly due to narrowing. Entries last at least as changes on the fly due to narrowing. Entries last at least as
long as the SAD entries, but tend to last even longer than that. long as the SAD entries, but tend to last even longer than that.
A naive implementation of a high availability cluster would have no A naive implementation of a high availability cluster would have no
synchronized state, and a failover would produce an effect similar to synchronized state, and a failover would produce an effect similar to
that of a rebooted gateway. [resumption] describes how new IKE and that of a rebooted gateway. [resumption] describes how new IKE and
IPsec SAs can be recreated in such a case. IPsec SAs can be recreated in such a case.
3.2. IKE Counters 3.3. IKE Counters
We can overcome the first problem described in Section 3.1, by We can overcome the first problem described in Section 3.2, by
synchronizing states - whenever an SA is created, we can synch this synchronizing states - whenever an SA is created, we can synch this
new state to all other members. However, those states are not only new state to all other members. However, those states are not only
long-lived, they are also ever changing. long-lived, they are also ever changing.
IKE has message counters. A peer may not process message n until IKE has message counters. A peer may not process message n until
after it has processed message n-1. Skipping message IDs is not after it has processed message n-1. Skipping message IDs is not
allowed. So a newly-active member needs to know the last message IDs allowed. So a newly-active member needs to know the last message IDs
both received and transmitted. both received and transmitted.
Often, it is feasible to synchronize the IKE message counters for Often, it is feasible to synchronize the IKE message counters for
every IKE exchange. This way, the newly active member knows what every IKE exchange. This way, the newly active member knows what
messages it is allowed to process, and what message IDs to use on IKE messages it is allowed to process, and what message IDs to use on IKE
requests, so that peers process them. requests, so that peers process them.
3.3. Outbound SA Counters 3.4. Outbound SA Counters
ESP and AH have an optional anti-replay feature, where every ESP and AH have an optional anti-replay feature, where every
protected packet carries a counter number. Repeating counter numbers protected packet carries a counter number. Repeating counter numbers
is considered an attack, so the newly-active member must not use a is considered an attack, so the newly-active member must not use a
replay counter number that has already been used. The peer will drop replay counter number that has already been used. The peer will drop
those packets as duplicates and/or warn of an attack. those packets as duplicates and/or warn of an attack.
Though it may be feasible to synchronize the IKE message counters, it Though it may be feasible to synchronize the IKE message counters, it
is almost never feasible to synchronize the IPsec packet counters for is almost never feasible to synchronize the IPsec packet counters for
every IPsec packet transmitted. So we have to assume that at least every IPsec packet transmitted. So we have to assume that at least
for IPsec, the replay counter will not be up-to-date on the newly- for IPsec, the replay counter will not be up-to-date on the newly-
active member, and the newly-active member may repeat a counter. active member, and the newly-active member may repeat a counter.
A possible solution is to synch replay counter information, not for A possible solution is to synch replay counter information, not for
each packet emitted, but only at regular intervals, say, every 10,000 each packet emitted, but only at regular intervals, say, every 10,000
packets or every 0.5 seconds. After a failover, the newly-active packets or every 0.5 seconds. After a failover, the newly-active
member advances the counters for outbound SAs by 10,000. To the peer member advances the counters for outbound SAs by 10,000. To the peer
this looks like up to 10,000 packets were lost, but this should be this looks like up to 10,000 packets were lost, but this should be
acceptable, as neither ESP nor AH guarantee reliable delivery. acceptable, as neither ESP nor AH guarantee reliable delivery.
3.4. Inbound SA Counters 3.5. Inbound SA Counters
An even tougher issue, is the synchronization of packet counters for An even tougher issue, is the synchronization of packet counters for
inbound SAs. If a packet arrives at a newly-active member, there is inbound SAs. If a packet arrives at a newly-active member, there is
no way to determine whether this packet is a replay or not. The no way to determine whether this packet is a replay or not. The
periodic synch does not solve the problem at all, because suppose we periodic synch does not solve the problem at all, because suppose we
synchronize every 10,000 packets, and the last synch before the synchronize every 10,000 packets, and the last synch before the
failover had the counter at 170,000. It is probable, though not failover had the counter at 170,000. It is probable, though not
certain, that packet number 180,000 has not yet been processed, but certain, that packet number 180,000 has not yet been processed, but
if packet 175,000 arrives at the newly- active member, it has no way if packet 175,000 arrives at the newly- active member, it has no way
of determining whether or not that packet has or has not already been of determining whether or not that packet has or has not already been
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challenge of a very narrow window for attack, and the need to time challenge of a very narrow window for attack, and the need to time
the attack to a failover event. Unless the attacker can actually the attack to a failover event. Unless the attacker can actually
cause the failover, this would be very difficult. It should be cause the failover, this would be very difficult. It should be
noted, though, that although this solution is acceptable as far as noted, though, that although this solution is acceptable as far as
RFC 4301 goes, it is a matter of policy whether this is acceptable. RFC 4301 goes, it is a matter of policy whether this is acceptable.
Another possible solution to the inbound SA problem is to rekey all Another possible solution to the inbound SA problem is to rekey all
child SAs following a failover. This may or may not be feasible child SAs following a failover. This may or may not be feasible
depending on the implementation and the configuration. depending on the implementation and the configuration.
3.5. Missing Synch Messages 3.6. Missing Synch Messages
The synch channel is very likely not to be infallible. Before The synch channel is very likely not to be infallible. Before
failover is detected, some synchronization messages may have been failover is detected, some synchronization messages may have been
missed. For example, the active member may have created a new Child missed. For example, the active member may have created a new Child
SA using message n. The new information (entry in the SAD and update SA using message n. The new information (entry in the SAD and update
to counters of the IKE SA) is sent on the synch channel. Still, with to counters of the IKE SA) is sent on the synch channel. Still, with
every possible technology, the update may be missed before the every possible technology, the update may be missed before the
failover. failover.
This is a bad situation, because the IKE SA is doomed. the newly- This is a bad situation, because the IKE SA is doomed. the newly-
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retransmissions and rejections, the whole IKE SA with all retransmissions and rejections, the whole IKE SA with all
associated IPsec SAs will get dropped. associated IPsec SAs will get dropped.
The above scenario may be rare enough that it is acceptable that on a The above scenario may be rare enough that it is acceptable that on a
configuration with thousands of IKE SAs, a few will need to be configuration with thousands of IKE SAs, a few will need to be
recreated from scratch or using session resumption techniques. recreated from scratch or using session resumption techniques.
However, detecting this may take a long time (several minutes) and However, detecting this may take a long time (several minutes) and
this negates the goal of creating a high availability cluster in the this negates the goal of creating a high availability cluster in the
first place. first place.
3.6. Simultaneous use of IKE and IPsec SAs by Different Members 3.7. Simultaneous use of IKE and IPsec SAs by Different Members
For load sharing clusters, all active members may need to use the For load sharing clusters, all active members may need to use the
same SAs, both IKE and IPsec. This is an even greater problem than same SAs, both IKE and IPsec. This is an even greater problem than
in the case of HA, because consecutive packets may need to be sent by in the case of HA, because consecutive packets may need to be sent by
different members to the same peer gateway. different members to the same peer gateway.
The solution to the IKE SA issue is up to the application. It's The solution to the IKE SA issue is up to the application. It's
possible to create some locking mechanism over the synch channel, or possible to create some locking mechanism over the synch channel, or
else have one member "own" the IKE SA and manage the child SAs for else have one member "own" the IKE SA and manage the child SAs for
all other members. For IPsec, solutions fall into two broad all other members. For IPsec, solutions fall into two broad
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cause problems with current gateways. It is also impossible to cause problems with current gateways. It is also impossible to
mandate against this, because the definition of "flow" varies from mandate against this, because the definition of "flow" varies from
one implementation to another. one implementation to another.
o Reply packets may arrive with an IPsec SA that is not "matched" to o Reply packets may arrive with an IPsec SA that is not "matched" to
the one used for the outgoing packets. Also, they might arrive at the one used for the outgoing packets. Also, they might arrive at
a different member. This problem is beyond the scope of this a different member. This problem is beyond the scope of this
document and should be solved by the application, perhaps by document and should be solved by the application, perhaps by
forwarding misdirected packets to the correct gateway for deep forwarding misdirected packets to the correct gateway for deep
inspection. inspection.
3.6.1. Outbound SAs using counter modes 3.7.1. Outbound SAs using counter modes
For SAs involving counter mode ciphers such as [CTR] or [GCM] there For SAs involving counter mode ciphers such as [CTR] or [GCM] there
is yet another complication. The initial vector for such modes must is yet another complication. The initial vector for such modes must
never be repeated, and senders use methods such as counters or LFSRs never be repeated, and senders use methods such as counters or LFSRs
to ensure this. An SA shared between more than one active member, or to ensure this. An SA shared between more than one active member, or
even failing over from one member to another need to make sure that even failing over from one member to another need to make sure that
they do not generate the same initial vector. See [COUNTER_MODES] they do not generate the same initial vector. See [COUNTER_MODES]
for a discussion of this problem in another context. for a discussion of this problem in another context.
3.7. Different IP addresses for IKE and IPsec 3.8. Different IP addresses for IKE and IPsec
In many implementations there are separate IP addresses for the In many implementations there are separate IP addresses for the
cluster, and for each member. While the packets protected by tunnel cluster, and for each member. While the packets protected by tunnel
mode child SAs are encapsulated in IP headers with the cluster IP mode child SAs are encapsulated in IP headers with the cluster IP
address, the IKE packets originate from a specific member, and carry address, the IKE packets originate from a specific member, and carry
that member's IP address. For the peer, this looks weird, as the that member's IP address. For the peer, this looks weird, as the
usual thing is for the IPsec packets to come from the same IP address usual thing is for the IPsec packets to come from the same IP address
as the IKE packets. as the IKE packets.
One obvious solution, is to use some fancy capability of the IKE host One obvious solution, is to use some fancy capability of the IKE host
to change things so that IKE packets also come out of the cluster IP to change things so that IKE packets also come out of the cluster IP
address. This can be achieved through NAT or through assigning address. This can be achieved through NAT or through assigning
multiple addresses to interfaces. This is not, however, possible for multiple addresses to interfaces. This is not, however, possible for
all implementations. all implementations.
[ARORA] discusses this problem in greater depth, and proposes another [ARORA] discusses this problem in greater depth, and proposes another
solution, that does involve protocol changes. solution, that does involve protocol changes.
3.9. Allocation of SPIs
The SPI associated with each child SA, and with each IKE SA, MUST be
unique relative to the peer of the SA. Thus, in the context of a
cluster, each cluster member MUST generate SPIs in a fashion that
avoids collisions (with other cluster members) for these SPI values.
The means by which cluster members achieve this requirement is a
local matter, outside the scope of this document.
4. Security Considerations 4. Security Considerations
Implementations running on clusters MUST be as secure as Implementations running on clusters MUST be as secure as
implementations running on single gateways. In other words, no implementations running on single gateways. In other words, no
extension or interpretation used to allow operation in a cluster may extension or interpretation used to allow operation in a cluster may
facilitate attacks that are not possible for single gateways. facilitate attacks that are not possible for single gateways.
Moreover, thought must be given to the synching requirements of any Moreover, thought must be given to the synching requirements of any
protocol extension, to make sure that it does not create an protocol extension, to make sure that it does not create an
opportunity for denial of service attacks on the cluster. opportunity for denial of service attacks on the cluster.
As mentioned in Section 3.4, allowing an inbound child SA to fail As mentioned in Section 3.5, allowing an inbound child SA to fail
over to another member has the effect of disabling replay counter over to another member has the effect of disabling replay counter
protection for a short time. Though the threat is arguably low, it protection for a short time. Though the threat is arguably low, it
is a policy decision whether this is acceptable. is a policy decision whether this is acceptable.
5. IANA Considerations 5. IANA Considerations
This document has no actions for IANA. This document has no actions for IANA.
6. Acknowledgements 6. Acknowledgements
This document is the collective work, and includes contribution from This document is the collective work, and includes contribution from
many people who participate in the IPsecME working group. many people who participate in the IPsecME working group.
The editor would particularly like to acknowledge the extensive The editor would particularly like to acknowledge the extensive
contribution of the following people (in alphabetical order): contribution of the following people (in alphabetical order):
Jitender Arora, Dan Harkins, Steve Kent, Tero Kivinen, Yaron Sheffer, Jitender Arora, Jean-Michel Combes, Dan Harkins, Steve Kent, Tero
Melinda Shore, and Rodney Van Meter. Kivinen, Yaron Sheffer, Melinda Shore, and Rodney Van Meter.
7. Change Log 7. Change Log
NOTE TO RFC EDITOR: REMOVE THIS SECTION BEFORE PUBLICATION NOTE TO RFC EDITOR: REMOVE THIS SECTION BEFORE PUBLICATION
Version 00 was identical to draft-nir-ipsecme-ipsecha-ps-00, re-spun Version 00 was identical to draft-nir-ipsecme-ipsecha-ps-00, re-spun
as an WG document. as an WG document.
Version 01 included closing issues 177, 178 and 180, with updates to Version 01 included closing issues 177, 178 and 180, with updates to
terminology, and added discussion of inbound SAs and the CTR issue. terminology, and added discussion of inbound SAs and the CTR issue.
Version 02 includes comments by Yaron Sheffer and the acknowledgement Version 02 includes comments by Yaron Sheffer and the acknowledgement
section. section.
Version 03 fixes some ID-nitsi, and adds the problem presented by Version 03 fixes some ID-nits, and adds the problem presented by
Jitender Arora in [ARORA]. Jitender Arora in [ARORA].
Version 04 fixes a spelling mistake, moves the scope discussion to a
subsection of its own (Section 3.1), and adds a short discussion of
the duplicate SPI problem, presented by Jean-Michel Combes.
8. Informative References 8. Informative References
[ARORA] Arora, J. and P. Kumar, "Alternate Tunnel Addresses for [ARORA] Arora, J. and P. Kumar, "Alternate Tunnel Addresses for
IKEv2", draft-arora-ipsecme-ikev2-alt-tunnel-addresses IKEv2", draft-arora-ipsecme-ikev2-alt-tunnel-addresses
(work in progress), April 2010. (work in progress), April 2010.
[COUNTER_MODES] [COUNTER_MODES]
McGrew, D. and B. Weis, "Using Counter Modes with McGrew, D. and B. Weis, "Using Counter Modes with
Encapsulating Security Payload (ESP) and Authentication Encapsulating Security Payload (ESP) and Authentication
Header (AH) to Protect Group Traffic", Header (AH) to Protect Group Traffic",
draft-ietf-msec-ipsec-group-counter-modes (work in draft-ietf-msec-ipsec-group-counter-modes (work in
progress), March 2010. progress), March 2010.
[CTR] Housley, R., "Using Advanced Encryption Standard (AES) [CTR] Housley, R., "Using Advanced Encryption Standard (AES)
Counter Mode", RFC 3686, January 2009. Counter Mode", RFC 3686, January 2009.
[GCM] Viega, J. and D. McGrew, "The Use of Galois/Counter Mode [GCM] Viega, J. and D. McGrew, "The Use of Galois/Counter Mode
(GCM) in IPsec Encapsulating Security Payload (ESP)", (GCM) in IPsec Encapsulating Security Payload (ESP)",
RFC 4106, June 2005. RFC 4106, June 2005.
[IKEv2bis]
Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen,
"Internet Key Exchange Protocol: IKEv2",
draft-ietf-ipsecme-ikev2bis (work in progress), May 2010.
[REDIRECT] [REDIRECT]
Devarapalli, V. and K. Weniger, "Redirect Mechanism for Devarapalli, V. and K. Weniger, "Redirect Mechanism for
IKEv2", RFC 5685, November 2009. IKEv2", RFC 5685, November 2009.
[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.
[RFC4301] Kent, S. and K. Seo, "Security Architecture for the [RFC4301] Kent, S. and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, December 2005. Internet Protocol", RFC 4301, December 2005.
[RFC4306] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", [RFC4306] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol",
RFC 4306, December 2005. RFC 4306, December 2005.
[RFC4718] Eronen, P. and P. Hoffman, "IKEv2 Clarifications and
Implementation Guidelines", RFC 4718, October 2006.
[VRRP] Nadas, S., "Virtual Router Redundancy Protocol (VRRP)", [VRRP] Nadas, S., "Virtual Router Redundancy Protocol (VRRP)",
RFC 5798, March 2010. RFC 5798, March 2010.
[resumption] [resumption]
Sheffer, Y. and H. Tschofenig, "IKEv2 Session Resumption", Sheffer, Y. and H. Tschofenig, "IKEv2 Session Resumption",
RFC 5723, January 2010. RFC 5723, January 2010.
Author's Address Author's Address
Yoav Nir Yoav Nir
 End of changes. 28 change blocks. 
43 lines changed or deleted 77 lines changed or added

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