Internet DRAFT - draft-mglt-ipsecme-clone-ike-sa
draft-mglt-ipsecme-clone-ike-sa
Network Working Group D. Migault (Ed)
Internet-Draft Ericsson
Intended status: Standards Track V. Smyslov
Expires: June 5, 2016 ELVIS-PLUS
December 3, 2015
Cloning IKE SA in the Internet Key Exchange Protocol Version 2 (IKEv2)
draft-mglt-ipsecme-clone-ike-sa-09.txt
Abstract
This document considers a VPN End User establishing an IPsec SA with
a Security Gateway using the Internet Key Exchange Protocol Version 2
(IKEv2), where at least one of the peers has multiple interfaces or
where Security Gateway is a cluster with each node having its own IP
address.
The protocol described allows a peer to clone an IKEv2 SA, where an
additional SA is derived from an existing one. The newly created IKE
SA is set without the IKEv2 authentication exchange. This IKE SA can
later be assigned to another interface or moved to another cluster
node.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on June 5, 2016.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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Table of Contents
1. Requirements notation . . . . . . . . . . . . . . . . . . . . 2
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Protocol Overview . . . . . . . . . . . . . . . . . . . . . . 5
5. Protocol Details . . . . . . . . . . . . . . . . . . . . . . 6
5.1. Support Negotiation . . . . . . . . . . . . . . . . . . . 6
5.2. Cloning the IKE SA . . . . . . . . . . . . . . . . . . . 6
5.3. Error Handling . . . . . . . . . . . . . . . . . . . . . 7
6. Payload Description . . . . . . . . . . . . . . . . . . . . . 7
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
8. Security Considerations . . . . . . . . . . . . . . . . . . . 8
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
10.1. Normative References . . . . . . . . . . . . . . . . . . 10
10.2. Informational References . . . . . . . . . . . . . . . . 10
Appendix A. Setting a VPN on Multiple Interfaces . . . . . . . . 10
A.1. Setting VPN_0 . . . . . . . . . . . . . . . . . . . . . . 11
A.2. Creating an additional IKE SA . . . . . . . . . . . . . . 12
A.3. Creating the Child SA for VPN_1 . . . . . . . . . . . . . 12
A.4. Moving VPN_1 on Interface_1 . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Requirements notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Introduction
The main scenario that motivated this document is a VPN End User
establishing VPN with a Security Gateway when at least one of the
peers has multiple interfaces. Figure 1 represents the case when the
VPN End User has multiple interfaces, Figure 2 represents the case
when the Security Gateway has multiple interfaces, and Figure 3
represents the case when both the VPN End User and the Security
Gateway have multiple interfaces. With Figure 1 and Figure 2, one of
the peers has n = 2 interfaces and the other has a single interface.
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This results in creating of up to n = 2 VPNs. With Figure 3, the VPN
End User has n = 2 interfaces and the Security Gateway has m = 2
interfaces. This may lead to up to m x n VPNs.
+------------+ +------------+
| | Interface_0 : VPN_0 | |
| ================= | |
| VPN | v | Security |
| End User | ================== Gateway |
| ================^ | |
| | Interface_1 : VPN_1 | |
+------------+ +------------+
Figure 1: VPN End User with Multiple Interfaces
+------------+ +------------+
| | Interface_0 : VPN_0 | |
| | ================== |
| VPN | v | Security |
| End User ================= | Gateway |
| | ^================= |
| | Interface_1 : VPN_1 | |
+------------+ +------------+
Figure 2: Security Gateway with Multiple Interfaces
+------------+ +------------+
| | Interface_0 Interface_0' | |
| ================================== |
| VPN | \\ // | Security |
| End User | // \\ | Gateway |
| ================================== |
| | Interface_1 Interface_1' | |
+------------+ +------------+
Figure 3: VPN End User and Security Gateway with Multiple Interfaces
With the current IKEv2 protocol [RFC7296], each VPN requires an IKE
SA, and setting an IKE SA requires an authentication. Authentication
might require multiple round trips and an activity from the End User
(like EAP-SIM [RFC4186] or EAP-TLS [RFC5216]) as well as crypto
operations that would introduce an additional delay.
Another scenario is a load-balancing solution. Load-sharing clusters
often are built to be transparent for VPN End Users. In the case of
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IPsec, this means that IKE and IPsec SA states are duplicated on
every cluster node where load balancer can redirect packets. The
drawback of such an approach is that anti-replay related data (in
particular Sequence Number) must be reliably synchronized between
participating nodes per every outgoing AH or ESP packet, which makes
building high-speed systems problematic. Another approach for
building load-balancing systems is to make VPN End Users aware of
them, which allows for having two or more Security Gateways sharing
the same ID, but each having its own IP address. In this case the
VPN End User first establishes an IKE SA with one of these gateways.
Then, at some point of time the gateway makes a decision to move
client to a different cluster node. This can be done with Redirect
Mechanism for IKEv2 [RFC5685]. The drawback of such an approach is
that it requires new IKE SA to be established from scratch, including
full authentication. In some cases this could be avoided by using
IKEv2 Session Resumption [RFC5723] with a new gateway. However this
requires VPN End User to know beforehand which new gateway to connect
to. So it is desirable to be able to clone existing IKE SA, to move
it to a different Security Gateway, and then to indicate VPN End User
to use this new SA. This would allow participating Security Gateways
to share the load between them.
This document introduces the possibility to clone the IKE SA in the
Internet Key Exchange Protocol Version 2 (IKEv2). The main idea is
that the peer with multiple interfaces sets the first IKE SA as
usual. Then it takes advantage of the fact that this SA is completed
and derives as many new parallel IKE SAs from it as the desired
number of VPNs. On each IKE SA a VPN is negotiated by creating one
or more IPsec SAs. This results in coexisting parallel VPNs. Then
the VPN End User moves each IPsec SA to its proper location using
MOBIKE (IKEv2 Mobility and Multihoming Protocol) [RFC4555].
Alternatively, the VPN End User may first move the IKE SAs and then
create the IPsec SAs.
Note that it is up to host's local policy which additional VPNs to
create and when to do it. The process of selecting address pairs for
migration is a local matter. Furthermore, in the case of multiple
interfaces on both ends, care should be taken to avoid the VPNs being
duplicated by both ends or moved to the both interfaces.
In addition multiple MOBIKE operation may be involved from the
Security Gateway or the VPN End User. Suppose, as depicted in
Figure 3 for example that the cloned VPN is between Interface _0 and
Interface_0', and the VPN End User and the Security Gateway want to
move it to Interface_1 and Interface_1'. The VPN End User may
initiate a MOBIKE exchange in order to move it to Interface_1, in
which case the cloned VPN is now between Interface_1 and
Interface_0'. Then the Security Gateway may also initiate a MOBIKE
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exchange in order to move the VPN to Interface_1' in which case the
VPN has reached its final destination.
The combination of the IKE SA cloning with MOBIKE protocol provides
IPsec communications with multiple interfaces the following
advantages. First, cloning the IKE SA requires very few
modifications to already existing IKEv2 implementations. Then, it
takes advantage of the already existing and widely deployed MOBIKE
protocol. Finally, it keeps a dedicated IKE SA for each VPN which
simplifies reachability tests and VPN maintenance.
Note also that the cloning of the IKE SA is independent from MOBIKE
and can also address other future scenarios not described in the
current document.
3. Terminology
This section defines terms and acronyms used in this document.
- VPN: Virtual Private Network - one or more Child (IPsec) SAs
created in tunnel mode between two peers.
- VPN End User: designates the end user that initiates the VPN with
a Security Gateway. This end user may be mobile and moves its
VPN from one Security Gateway to another.
- Security Gateway: designates a point of attachment for the VPN
service. In this document, the VPN service is provided by
multiple Security Gateways. Each Security Gateway may be
considered as a specific hardware.
- IKE SA: The IKE SA (IKE Security Association) is defined in
[RFC7296].
4. Protocol Overview
This document specifies how to create a clone of existing IKE SAs
without performing new authentication. In order to achieve this
goal, the document proposes that the two peers agree upon their
ability to clone the IKE SA. This is done during the IKE_AUTH
exchange by exchanging the CLONE_IKE_SA_SUPPORTED notifications. To
create a new parallel IKE SA, one of the peers initiates a
CREATE_CHILD_SA exchange as if it would rekey the existing IKE SA.
In order to indicate the current IKE SA must not be deleted, the
initiator includes the CLONE_IKE_SA notification in the
CREATE_CHILD_SA exchange. This results in two parallel IKE SAs.
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Note, that without the CLONE_IKE_SA notification the old IKE SA would
be deleted after the rekey is successfully completed (as specified in
Section 2.8 of [RFC7296].
5. Protocol Details
5.1. Support Negotiation
The initiator and the responder indicate their support for cloning
IKE SA by exchanging the CLONE_IKE SA_SUPPORTED notifications. This
notification MUST be sent in the IKE_AUTH exchange (in case of
multiple IKE_AUTH exchanges - in the first IKE_AUTH message from
initiator and in the last IKE_AUTH message from responder). If both
initiator and responder send this notification during the IKE_AUTH
exchange, peers may clone this IKE SA. In the other case the IKE SA
MUST NOT be cloned.
Initiator Responder
-------------------------------------------------------------------
HDR, SA, KEi, Ni -->
<-- HDR, SA, KEr, Nr
HDR, SK {IDi, AUTH,
SA, TSi, TSr,
N(CLONE_IKE_SA_SUPPORTED)} -->
<-- HDR, SK {IDr, AUTH,
SA, TSi, TSr,
N(CLONE_IKE_SA_SUPPORTED)}
5.2. Cloning the IKE SA
The initiator of the rekey exchange includes the CLONE_IKE_SA
notification in a CREATE_CHILD_SA request for rekeying the IKE SA.
The CLONE_IKE_SA notification indicates that the current IKE SA will
not be immediately deleted once the new IKE SA is created. Instead
two parallel IKE SAs are expected to coexist. The current IKE SA
becomes the old IKE SA and the newly negotiated IKE SA becomes the
new IKE SA. The CLONE_IKE_SA notification MUST appear only in
request message of the CREATE_CHILD_SA exchange concerning the IKE SA
rekey. If the CLONE_IKE_SA notification appears in any other
message, it MUST be ignored.
Initiator Responder
-------------------------------------------------------------------
HDR, SK {N(CLONE_IKE_SA), SA, Ni, KEi} -->
If the CREATE_CHILD_SA request is concerned with an IKE SA rekey and
contains the CLONE_IKE_SA notification, the responder proceeds to the
IKE SA rekey, creates the new IKE SA, and keeps the old IKE SA. No
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additional Notify Payloads are included in the CREATE_CHILD_SA
response as represented below:
<-- HDR, SK {SA, Nr, KEr}
When the IKE SA is cloned, peers MUST NOT transfer existing Child
SAs, that were created by the old IKE SA, to the newly created IKE
SA. So, all signalling messages, concerning those Child SAs would
continue to be sent over the old IKE SA. This is different from the
regular IKE SA rekey in IKEv2.
5.3. Error Handling
There may be conditions when responder for some reason is unable or
unwilling to clone the IKE SA. This inability may be temporary or
permanent.
Temporary inability occurs when the responder doesn't have enough
resources at the moment to clone an IKE SA or when the IKE SA is
being deleted by the responder. In this case the responder SHOULD
reject the request to clone the IKE SA with the TEMPORARY_FAILURE
notification.
<-- HDR, SK {N(TEMPORARY_FAILURE)}
After receiving this notification the initiator MAY retry its request
after waiting some period of time. See Section 2.25 of [RFC7296] for
details.
In some cases, responder may have restrictions on the number of co-
existing IKE SAs with one peer. These restrictions may be either
implicit (some devices may have enough resources to handle only a few
IKE SAs) or explicit (provided by some configuration parameter). If
the initiator wants to clone more IKE SAs, than responder is able or
is configured to handle, the responder SHOULD reject the request with
the NO_ADDITIONAL_SAS notification.
<-- HDR, SK {N(NO_ADDITIONAL_SAS)}
This condition is considered permanent and the initiator SHOULD NOT
retry to clone an IKE SA until some of existing SAs with the
responder are deleted.
6. Payload Description
Figure 4 illustrates the Notify Payload packet format as described in
section 3. 10 of [RFC7296]. This format is used for both the
CLONE_IKE_SA and the CLONE_IKE_SA_SUPPORTED notifications.
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The CLONE_IKE_SA_SUPPORTED notification is used in an IKEv2 exchange
of type IKE_AUTH and the CLONE_IKE_SA is used in an IKEv2 exchange of
type CREATE_CHILD_SA.
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 | Notify Message Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Notify Payload
The fields Next Payload, Critical Bit, RESERVED and Payload Length
are defined in [RFC7296]. Specific fields defined in this document
are:
- Protocol ID (1 octet): set to zero.
- SPI Size (1 octet): set to zero.
- Notify Message Type (2 octets): Specifies the type of notification
message. It is set to <TBA by IANA> for the CLONE_IKE_SA
notification or to <TBA by IANA> for the CLONE_IKE_SA_SUPPORTED
Notification.
7. IANA Considerations
IANA is requested to allocate two values in the "IKEv2 Notify Message
Types - Status Types registry":
IKEv2 Notify Message Types - Status Types
-----------------------------------------
<TBA> CLONE_IKE_SA_SUPPORTED
<TBA> CLONE_IKE_SA
8. Security Considerations
The protocol defined in this document does not modify IKEv2.
Security considerations for cloning an IKE SA are mostly the same as
those for base IKEv2 protocol described in [RFC7296].
Cloning an IKE SA provides the ability for an initiator to duplicate
existing SAs. As a result it may influence any accounting or control
mechanisms based on a single IKE SA per authentication.
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Suppose a system has a limit on the number of IKE SAs it can handle.
In this case, cloning an IKE SA may provide a way for resource
exhaustion, as a single end user may populate multiple IKE SAs.
Suppose a system shares the IPsec resources by limiting the number of
Child SAs per IKE SA. With a single IKE SA per end user, this
provides an equal resource sharing. In this case, cloning the IKE SA
provides means for an end user to overpass this limit. Such system
should evaluate the number of Child SAs over the number of all IKE
SAs associated to an end user.
Note, that these issues are not unique to the ability of cloning the
IKE SA, as multiple IKE SAs between two peers may be created without
involving a cloning method. Note also, that implementation can
always limit the number of cloned IKE SAs.
Suppose VPN or any other IPsec based service monitoring is based on
the liveliness of the first IKE SA. Such a system considers a
service is accessed or used from the time IKE performs an
authentication to the time the IKE SA is deleted. Such accounting
methods were fine as any IKE SA required an authentication exchange.
As cloning the IKE SA skips the authentication phase, it may make it
possible to delete the initial IKE SA while the service is being used
on the cloned IKE SA. Such accounting methods should consider the
service is being used from the first IKE SA establishment to until
the last IKE SA is removed.
When cloning, an IKE SA is used to build load-balancing systems, then
there is a necessity to transfer IKE SA states between nodes of a
load-sharing cluster. Since IKE SA state contains sensitive
information, such as session keys, implementations must take all due
precautions. Such precautions might include using technical and/or
administrative means to protect IKE SA state data. The details of
what is transferred and how it is protected are out of scope of this
document.
9. Acknowledgments
The ideas of this draft came from various inputs from the ipsecme WG
and from discussions with Tero Kivinen and Michael Richardson. Yaron
Sheffer, Tero Kivinen provided significant inputs to set the current
design of the protocol as well as its designation.
10. References
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10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/
RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC4555] Eronen, P., "IKEv2 Mobility and Multihoming Protocol
(MOBIKE)", RFC 4555, DOI 10.17487/RFC4555, June 2006,
<http://www.rfc-editor.org/info/rfc4555>.
[RFC7296] Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T.
Kivinen, "Internet Key Exchange Protocol Version 2
(IKEv2)", STD 79, RFC 7296, DOI 10.17487/RFC7296, October
2014, <http://www.rfc-editor.org/info/rfc7296>.
10.2. Informational References
[RFC4186] Haverinen, H., Ed. and J. Salowey, Ed., "Extensible
Authentication Protocol Method for Global System for
Mobile Communications (GSM) Subscriber Identity Modules
(EAP-SIM)", RFC 4186, DOI 10.17487/RFC4186, January 2006,
<http://www.rfc-editor.org/info/rfc4186>.
[RFC5216] Simon, D., Aboba, B., and R. Hurst, "The EAP-TLS
Authentication Protocol", RFC 5216, DOI 10.17487/RFC5216,
March 2008, <http://www.rfc-editor.org/info/rfc5216>.
[RFC5685] Devarapalli, V. and K. Weniger, "Redirect Mechanism for
the Internet Key Exchange Protocol Version 2 (IKEv2)", RFC
5685, DOI 10.17487/RFC5685, November 2009,
<http://www.rfc-editor.org/info/rfc5685>.
[RFC5723] Sheffer, Y. and H. Tschofenig, "Internet Key Exchange
Protocol Version 2 (IKEv2) Session Resumption", RFC 5723,
DOI 10.17487/RFC5723, January 2010,
<http://www.rfc-editor.org/info/rfc5723>.
Appendix A. Setting a VPN on Multiple Interfaces
This section is informational and exposes how a VPN End User as
illustrated in Figure 1 can build two VPNs on its two interfaces
without multiple authentications. Other cases represented in
Figure 2 and Figure 3 are similar and can be easily derived from this
case. The mechanism is based on cloning the IKE SA and the MOBIKE
extension [RFC4555].
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A.1. Setting VPN_0
First, the VPN End User negotiates a VPN using one interface. This
involves regular IKEv2 exchanges. In addition, the VPN End User and
the Security Gateway advertise their support for MOBIKE. At the end
of the IKE_AUTH exchange, VPN_0 is set as represented in Figure 5.
+------------+ +------------+
| | Interface_0 : VPN_0 | |
| ================= | |
| VPN | v | Security |
| End User | ================== Gateway |
| = | |
| | Interface_1 | |
+------------+ +------------+
Figure 5: VPN End User Establishing VPN_0
The exchanges are completely described in [RFC7296] and [RFC4555].
First, peers negotiate IKE SA parameters and exchange nonces and
public keys in IKE_SA_INIT exchange. In the figure below they also
proceed to NAT detection because of the use of MOBIKE.
Initiator Responder
-------------------------------------------------------------------
(IP_I0:500 -> IP_R:500)
HDR, SA, KEi, Ni,
N(NAT_DETECTION_SOURCE_IP),
N(NAT_DETECTION_DESTINATION_IP) -->
<-- (IP_R:500 -> IP_I0:500)
HDR, SA, KEr, Nr,
N(NAT_DETECTION_SOURCE_IP),
N(NAT_DETECTION_DESTINATION_IP)
Then the initiator and the responder proceed to the IKE_AUTH
exchange, advertise their support for MOBIKE and their ability to
clone the IKE SA - with the MOBIKE_SUPPORTED and the
CLONE_IKE_SA_SUPPORTED notifications - and negotiate the Child SA for
VPN_0. Optionally, the initiator and the responder can advertise
their multiple interfaces using the ADDITIONAL_IP4_ADDRESS and/or
ADDITIONAL_IP6_ADDRESS notifications.
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(IP_I0:4500 -> IP_R:4500)
HDR, SK {IDi, AUTH,
SA, TSi, TSr,
N(MOBIKE_SUPPORTED),
[N(ADDITIONAL_IP*_ADDRESS)+,]
N(CLONE_IKE_SA_SUPPORTED)} -->
<-- (IP_R:4500 -> IP_I0:4500)
HDR, SK {IDr, AUTH,
SA, TSi, TSr,
N(MOBIKE_SUPPORTED),
[N(ADDITIONAL_IP*_ADDRESS)+,]
N(CLONE_IKE_SA_SUPPORTED)}
A.2. Creating an additional IKE SA
In our case the VPN End User wants to establish an additional VPN
with its Interface_1. The VPN End User will first establish a
parallel IKE SA using a CREATE_CHILD_SA that concerns an IKE SA rekey
associated with a CLONE_IKE_SA notification. This results in two
separate IKE SAs between the VPN End User and the Security Gateway.
Currently both IKE SAs are set using Interface_0 of the VPN End User.
Initiator Responder
-------------------------------------------------------------------
(IP_I0:4500 -> IP_R:4500)
HDR, SK {N(CLONE_IKE_SA),
SA, Ni, KEi} -->
<-- (IP_R:4500 -> IP_I0:4500)
HDR, SK {SA, Nr, KEr}
A.3. Creating the Child SA for VPN_1
Once the new IKE SA has been created, the VPN End User can initiate a
CREATE_CHILD_SA exchange that concerns the creation of a Child SA for
VPN_1. The newly created VPN_1 will use Interface_0 of the VPN End
User.
It is out of scope for the document to define how the VPN End User
handles traffic with multiple interfaces. The VPN End User can use
the same inner IP address on its multiple interfaces. In this case,
the same Traffic Selectors (that is the IP address used for VPN_0 and
VPN_1) can match for both VPNs VPN_0 and VPN_1. The VPN End User
must be aware of such a match and be able to manage it. It can for
example use distinct Traffic Selectors on both VPNs using different
ports, manage the order of its SPD or have SPD defined per
interfaces. Defining these mechanisms are out of scope of this
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document. Alternatively, the VPN End User can use a different inner
IP address for each interface.
The creation of VPN_1 is performed via the newly created IKE SA as
follows:
Initiator Responder
-------------------------------------------------------------------
(IP_I0:4500 -> IP_R:4500)
HDR(new), SK(new) {SA, TSi, TSr} -->
<-- (IP_R:4500 -> IP_I0:4500)
HDR(new), SK(new) {SA, TSi, TSr}
The resulting configuration is depicted in Figure 6. VPN_0 and VPN_1
have been created, but both are using the same Interface:
Interface_0.
+------------+ +------------+
| | Interface_0 : VPN_0, VPN_1 | |
| ==================== | |
| VPN ================= v | Security |
| End User | v =============== Gateway |
| | ================== |
| | Interface_1 | |
+------------+ +------------+
Figure 6: VPN End User Establishing VPN_0 and VPN_1
A.4. Moving VPN_1 on Interface_1
In this section, MOBIKE is used to move VPN_1 on interface_1. The
exchange is described in [RFC4555].
(IP_I1:4500 -> IP_R:4500)
HDR(new), SK(new) {N(UPDATE_SA_ADDRESSES),
N(NAT_DETECTION_SOURCE_IP),
N(NAT_DETECTION_DESTINATION_IP),
N(COOKIE2)} -->
<-- (IP_R:4500 -> IP_I1:4500)
HDR(new), SK(new) {
N(NAT_DETECTION_SOURCE_IP),
N(NAT_DETECTION_DESTINATION_IP),
N(COOKIE2)}
This results in the situation as described in Figure 7.
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+------------+ +------------+
| | Interface_0 : VPN_0 | |
| ================== | |
| VPN | v | Security |
| End User | ================= Gateway |
| =================^ | |
| | Interface_1 : VPN_1 | |
+------------+ +------------+
Figure 7: VPN End User with Multiple Interfaces
Authors' Addresses
Daniel Migault
Ericsson
8400 boulevard Decarie
Montreal, QC H4P 2N2
Canada
Email: daniel.migault@ericsson.com
Valery Smyslov
ELVIS-PLUS
PO Box 81
Moscow (Zelenograd) 124460
Russian Federation
Phone: +7 495 276 0211
Email: svan@elvis.ru
Migault (Ed) & Smyslov Expires June 5, 2016 [Page 14]
