wdiff rfc6909.original rfc6909.txt

NETEXT WG
Internet Engineering Task Force (IETF) S. Gundavelli, Ed.
Internet-Draft
Request for Comments: 6909 Cisco
Intended status:
Category: Standards Track X. Zhou
Expires: August 28, 2013
ISSN: 2070-1721 ZTE Corporation
J. Korhonen
Nokia Siemens Networks
Renesas Mobile
G. Feige
R. Koodli
Cisco
February 24,
April 2013

IPv4 Traffic Offload Selector Option for Proxy Mobile IPv6
draft-ietf-netext-pmipv6-sipto-option-12.txt

Abstract

This specification defines a new mobility option, the IPv4 Traffic
Offload Selector option, for Proxy Mobile IPv6. This option can be
used by the local mobility anchor and the mobile access gateway for
negotiating IPv4 traffic offload policy for a mobility session.
Based on the negotiated IPv4 traffic offload policy, a mobile access
gateway can selectively offload some of the IPv4 traffic flows in the
access network instead of tunneling back to the local mobility anchor
in the home network.

Status of this This Memo

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Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.

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This Internet-Draft will expire on August 28, 2013.
http://www.rfc-editor.org/info/rfc6909.

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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 ....................................................2
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4 .....................................3
2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4 ................................................3
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 ................................................3
3. Solution Overview . . . . . . . . . . . . . . . . . . . . . . 4 ...............................................4
3.1. IPv4 Traffic Offload Selector Option . . . . . . . . . . . 7 .......................6
3.2. MAG Considerations . . . . . . . . . . . . . . . . . . . . 9 .........................................8
3.3. LMA Considerations . . . . . . . . . . . . . . . . . . . . 10 .........................................9
4. Protocol Configuration Variables . . . . . . . . . . . . . . . 12 ...............................11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 ............................................11
6. Security Considerations . . . . . . . . . . . . . . . . . . . 13
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. Normative References . . . . . . . . . . . . . . . . . . . 14 ........................................12
7. Acknowledgements ...............................................12
8. References .....................................................13
8.1. Normative References ......................................13
8.2. Informative References . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 ....................................13

1. Introduction

Mobile Operators operators are expanding their network coverage by integrating
various access technology domains (Ex: (e.g., Wireless LAN, CDMA, LTE) and
Long-Term Evolution (LTE)) into a common IP mobility core. The 3GPP Third
Generation Partnership Project (3GPP) S2a Proxy Mobile IPv6 [TS23402]
reference point, specified by the 3GPP system architecture architecture, defines
the protocol inter-working interworking for building such integrated multi-access
network.
networks. In this scenario, the mobile node's IP traffic is always
tunneled back from the mobile access gateway [RFC5213] in the access
network to the local mobility anchor in the home network. Currently,
there is no mechanism for allowing some of the subscriber's IP flows
to be offloaded in the access network.

With the exponential growth in the mobile data traffic, mobile operators
are exploring new ways to offload some of the IP traffic flows at the
nearest access edge. The offload is intended either for local
service access in the access network, network or for internet Internet offload through
the access network when there is an internet Internet peering point. Not all
IP traffic flows needs need to be routed back to the home network,
some of network; the non-essential
traffic which that does not require IP mobility support can be offloaded at
the mobile access gateway in the access network. This approach
allows efficient usage of the mobile packet
core core, which helps in
lowering transport costs. The To identify the IP flows that need to be
offloaded, the local mobility anchor in the home network can deliver
the IP flow policy to the mobile access gateway in the access network, for identifying the IP
flows that need
network. It is up to be offloaded. It's a policy decision as an operator's discretion to which classify the
traffic an operator deems as non-essential. for offload. One operator might choose to offload everything
except traffic (such as Voice over IP) that requires QoS services.
Another might choose to offload only HTTP traffic. From the point of view of this specification, it This
specification is only about concerned with matching IP traffic matching against a
given flow selector and classification of IP traffic for offload. offloading
purposes. This approach has one limitation with respect to
identifying encrypted traffic: IPsec encrypted IPsec-encrypted traffic with no
visibility into the application payload cannot be selected for
offload.

This document defines a new mobility option, the IPv4 Traffic Offload
Selector option (Section 3.1) (see Section 3.1), for Proxy Mobile IPv6 (PMIPv6).
This option can be used by the local mobility anchor for delivering and the mobile
access gateway for negotiating IPv4 traffic offload policy associated with for a
mobility session to the
mobile access gateway. session. This IPv4 traffic offload policy identifies the
flow selectors that can be used for selecting the flows for
offloading them that can be
offloaded at the access edge. Since, Since the mobile node's IP address
topologically belongs to the home network, the offloaded IPv4 traffic
flows may need to be NAT [RFC2663] translated. These offloaded flows
will not have mobility support as the NAT becomes the anchor point
for those flows. However, when the traffic is offloaded for local
service access as opposed to internet Internet offload, NAT translation may
not be needed, needed if the mobile access gateways gateway is in the path for the
return traffic. The decision on when to apply NAT translation can be
based on local configuration on the mobile access gateway. There are
better ways to address the offload problem for
IPv6 IPv6, and with the
goal not to create a NAT66 requirement, this specification therefore
does not support address traffic offload support for IPv6 flows.

2. Conventions and Terminology

2.1. Conventions

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 RFC 2119 [RFC2119].

2.2. Terminology

All the mobility related mobility-related terms used in this document are to be
interpreted as defined in the base Proxy Mobile IPv6 specifications
[RFC5213] and [RFC5844]. Additionally, this document uses the following
terms:

IP Flow

IP Flow flow [RFC5101] represents a set of IP packets that match a
traffic selector. selector (TS). The selector is typically based on the
source IP address, destination IP address, source port,
destination port port, and other fields in upper layer upper-layer headers.

IP Traffic Offload

The

IP traffic offload is the approach of selecting specific IP flows
and routing them through the access network, network instead of tunneling
them to the home network. Offload can also be between two access
networks
(Example: (e.g., moving some of the traffic from LTE access to WLAN
access).

3. Solution Overview

Figure 1 illustrates the scenario where the mobile access gateway in
an access network has enabled IPv4 traffic offload support for a
mobility session. The offload decision is based on the IPv4 traffic
offload policy that it negotiated with the local mobility anchor in
the home network. For example, all the HTTP flows may be offloaded
at the mobile access gateway gateway, and all the other flows for that
mobility session are tunneled back to the local mobility anchor. The
offloaded flows typically have to be typically NAT translated translated, and this
specification does not impose any restrictions on the location of the
NAT function. It is possible for the NAT function to be co-located
with the mobile access gateway or located somewhere in at the edge of
the access network. When the NAT function is not co-located with the
mobile access gateway, offloaded traffic flows must be delivered
through the local access network between the mobile access gateway
and the NAT function, for example example, through a VLAN or a point-to-point
link. The exact means for this delivery are outside the scope of
this document. If the offloaded IPv4 flows are for local service
access and reverse traffic from the local service device can be
routed to the mobile node through the mobile access gateway, the
offloaded flows may be delivered directly to a local service device.

The traffic selectors in the IPv4 traffic offload policy are used to
classify the traffic, so it can be offloaded to at the access network.
These parameters include Source source IP address, Destination destination IP address,
TCP/UDP Port port numbers, and other fields. The format of the IPv4
Binary Traffic Selector
binary traffic selector is specified in section Section 3.1 of [RFC6088].

_----_
_( )_
:-----------------( Internet )---------------:
| (_ _) |
| '----' |
| |
: |
(IPv4 Traffic Offload Point) |
: |
| |
........................................................|....
| | |
+--------+ | +---------------------+ |
| Local | | | Services requiring | |
|Services| | | mobility, or service| |
+--------+ | | treatment | |
| | +---------------------+ |
| +---+ | |
| |NAT| | |
| +---+ | |
+-----| _----_ | |
+-----+ _( )_ +-----+ |
[MN]----| MAG |======( IP )======| LMA |----------
+-----+ (_ _) +-----+ Internet
'----'
.
.
[Access Network] . [Home Network]
..........................................................

Figure 1: IPv4 Traffic Offload Support at the MAG

Figure 2 explains the operational sequence of the Proxy Mobile IPv6
protocol signaling message exchange between the mobile access gateway
(MAG) and the local mobility anchor (LMA) for negotiating the IPv4 Traffic
Offload
traffic offload selectors. The details related to DHCP transactions, transactions
or Router Advertisements on the access link are not shown here as
that is not the key focus of this specification. The use of IPv4
Traffic Selector option in the Proxy Binding Update is for allowing
the MAG to request the LMA for the IPv4 Traffic Offload traffic offload policy.

MN MAG(NAT) LMA
|------>| | 1. Mobile Node Attach
| |------->| 2. Proxy Binding Update (IPv4TS)
| |<-------| 3. Proxy Binding Acknowledgement (IPv4TS)
| |========| 4. Tunnel/Route Setup
| + | 5. Installing the traffic offload rules
|------>| | 6. IPv4 packet from mobile node
| + | 7. Offload rule applied (Tunnel/offload)
| | |

Figure 2: Exchange of IPv4 Traffic Offload Selectors

3.1. IPv4 Traffic Offload Selector Option

A new mobility option, the IPv4 Traffic Offload Selector option, option (53),
is defined for using it use in Proxy Binding Update (PBU) and Proxy Binding
Acknowledgement (PBA) messages exchanged between a mobile access
gateway and a local mobility anchor. This option is used for
carrying the IPv4 traffic offload policy. This policy identifies the
IPv4 traffic flow selectors that can be used by the mobile access
gateway for enforcing the offload policy.

The alignment requirement for this option is 4n.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|M| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Traffic Selector Sub-option ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 3: IPv4 Traffic Offload Selector Option

Type
<IANA-1>
53

Length
8-bit unsigned integer indicating the length in octets of the
option, excluding the type and length fields.

Offload Mode (M) Flag
This field indicates the offload mode.

If the (M) flag value is set to a value of (0), it is an
indication that the IPv4 flow(s) matching that match the traffic
selectors in the Traffic Selector sub-option [RFC6089] and that
are associated to that mobility session have to be offloaded at
the mobile access gateway. All the other IPv4 flows associated
with that mobility session and not matching the traffic
selectors have to be tunneled to the local mobility anchor.

If the (M) flag value is set to a value of (1), it is an
indication that all the IPv4 flows associated to that mobility
session except the IPv4 flow(s) matching the traffic selectors
in the Traffic Selector sub-option have to be offloaded at the
mobile access gateway. All the IPv4 flows associated with that
mobility session and matching the traffic selectors have to be
tunneled back to the local mobility anchor.

Reserved
This field is unused for now. The value MUST be initialized to 0
by the sender and MUST be ignored by the receiver.

Traffic Selector Sub-option
The traffic selector Traffic Selector sub-option includes the parameters used to
match packets for a specific flow binding. This is an optional
sub-option when the IPv4 Traffic Selector option is carried in a
Proxy Binding Update message, message but is a mandatory sub-option when
the IPv4 Traffic Selector option is carried in a Proxy Binding
Acknowledgement message. The format of the Traffic Selector sub-
option is defined in section Section 4.2.1.4 of [RFC6089]. This sub-
option includes a TS Format field, which identifies the format of
the flow specification included in that sub-option. The values
for that field are defined in section Section 3 of [RFC6088] and are
repeated here for completeness. When the value of the TS Format
field is set to (1), the format that follows is the IPv4 Binary Traffic
Selector binary
traffic selector specified in section Section 3.1 of [RFC6088] [RFC6088], and that
support is mandatory for this specification. The text specified
in this section takes precedence over what is specified in
[RFC6088] and [RFC6089].

1: IPv4 binary traffic selector. selector

2: IPv6 binary traffic selector (Not (not used by this
specification)

3.2. MAG Considerations

o If the mobile access gateway is configured to support enable IPv4 Traffic
Offload traffic
offload support, then it includes the IPv4 Traffic Offload
Selector option (Section 3.1) in the Proxy Binding Update message
that it sends to the local mobility anchor. Optionally, the
mobile access gateway can also propose a specific offload policy.

* The mobile access gateway MAY choose not to propose any
specific IPv4 traffic offload policy but request the local
mobility anchor for the offload policy. In this scenario, the
IPv4 Traffic Offload Selector option that is carried in the
Proxy Binding Update message does not include the Traffic
Selector sub-option (Section 3.1) (see Section 3.1), and the (M) flag (see
Section 3.1 3.1) in the option MUST be set to a value of (0).
Including the IPv4 Traffic Offload Selector option in the Proxy
Binding Update without the Traffic Selector Sub-option sub-option serves
as an indication that the mobile access gateway is not
proposing any specific offload policy for that mobility
session, but rather it makes a request to the local mobility
anchor to provide the offload policy.

* The mobile access gateway MAY choose to propose a specific IPv4
traffic offload policy by including the Traffic Selector sub-
option in the IPv4 Traffic Offload Selector option (see
Section 3.1. 3.1). The specific details on how the mobile access
gateway obtains the mobile node's IPv4 traffic offload policy, is policy
are outside the scope of this document. When this offload
policy is included in the Proxy Binding Update message, it
serves as a proposal to the local mobility anchor, which the anchor. The local
mobility anchor can override with its own offload policy, or it
can agree to the proposed policy. The offload policy has to be
translated to a set of selectors that can be used to match the
mobile node's IP flows flows, and these selectors have to be carried
in the Traffic Selector
Sub-option. sub-option. The Traffic Selector sub-option sub-
option MUST be constructed as specified section in Section 4.2.1.4 of
[RFC6089]. This sub-option includes a Traffic Selector TS Format field, which
identifies the format of the flow specification included in
that the
sub-option. The values for that field and the corresponding
message format are defined in section 3.0 Section 3.1 of [RFC6088].
Considerations from Section 3.1 apply with respect to setting
the Offload Mode (M) flag.

o When sending a Proxy Binding Update either for Binding lifetime
extension, Lifetime
Extension or for Binding De-Registration, the mobile access
gateway SHOULD copy the IPv4 Traffic Offload Selector option from
the initial Proxy Binding Update message. Considerations from
section
Sections 6.9.1.3 [RFC5213] and section 6.9.1.4 of [RFC5213] MUST be applied.

o If the mobile access gateway is not configured to support IPv4
traffic offload support as specified in this specification, but if
the received Proxy Binding Acknowledgement message has the IPv4
Traffic Offload Selector option, then the mobile access gateway
MUST ignore the option and process the rest of the message as per
[RFC5213].

o If there is no IPv4 Traffic Offload Selector option in the Proxy
Binding Acknowledgement message received from the local mobility
anchor, it is an indication that the local mobility anchor did not
enable IPv4 Traffic Offload traffic offload support for that mobility session.
The mobile access gateway upon
Upon accepting the Proxy Binding Acknowledgement message message, the
mobile access gateway SHOULD NOT enable IPv4 traffic offload
support for that mobility session.

o If there is an IPv4 Traffic Offload Selector option in the Proxy
Binding Acknowledgement message, then the mobile access gateway
SHOULD enable the IPv4 traffic offload support for that mobility
session. The mobility access gateway has to provision the data
plane using the flow selectors present in the Traffic Selector
Sub-option.
sub-option. The IPv4 flows matching the flow selectors have to be
offloaded,
offloaded or tunneled back based to the local mobility anchor
based on the value of the Offload Mode (M) flag (see Section 3.1. 3.1).

3.3. LMA Considerations

o If the received Proxy Binding Update message does not include the
IPv4 Traffic Offload Selector option (Section 3.1), then the local
mobility anchor MUST NOT enable IPv4 Traffic Offload traffic offload support for
that mobility session session, and the Proxy Binding Acknowledgement
message that will be sent in response MUST NOT contain the IPv4
Traffic Offload Selector option.

o If the Proxy Binding Update message includes the IPv4 Traffic
Offload Selector option, but the local mobility anchor is not
configured to support IPv4 Traffic Offload traffic offload support, then the local
mobility anchor will ignore the option and process the rest of the
message as per [RFC5213]. This would have no effect on the
operation of the rest of the protocol.

o If the Proxy Binding Update message has the IPv4 Traffic Offload
Selector option and if the local mobility anchor is configured to
support IPv4 Traffic Offload traffic offload support, then the local mobility
anchor MUST enable IPv4 Traffic Offload traffic offload support for that mobility
session. The Proxy Binding Acknowledgement message that will be
sent in response MUST include the IPv4 Traffic Offload Selector
option. The following considerations apply with respect to
constructing the IPv4 Traffic Offload Selector option.

* The local mobility anchor can obtain the offload policy from
the local configuration store, store or from a network function such
as from AAA (Authentication, Authorization Authorization, and Accounting), Accounting) or PCRF
(Policy Charging and Rules Function)). Charging Rule Function). The offload policy has to
be translated to a set of selectors that can be used to match
the mobile node's IP flows flows, and these selectors have to be
carried in the Traffic Selector Sub-option. sub-option. The Traffic
Selection Sub-option
Selector sub-option MUST be constructed as specified in
section Section
4.2.1.4 of [RFC6089]. Considerations from Section 3.1 apply
with respect to the Offload Mode Flag (M) flag setting.

* If the Proxy Binding Update message includes a specific IPv4
Traffic Offload
traffic offload policy proposal in the form of the Traffic
Selector
Sub-option sub-option [RFC6089], then the local mobility anchor
MAY choose to agree to that request by including the same IPv4 Traffic
Offload
traffic offload policy in the Proxy Binding Acknowledgement
message. This implies the local mobility anchor has agreed to
the IPv4 traffic offload policy provided by the mobile access gateway provided IPv4 Traffic Offload policy.
gateway. The local mobility anchor MAY also choose to override
the request by including a different IPv4 Traffic Offload traffic offload
policy that it wants the mobile access gateway to enforce for
that mobility session. This is entirely based on the policy
configuration on the local mobility anchor.

* The IPv4 traffic offload policy that is sent to the mobile
access gateway has to be specific to the mobility session
identified using the Mobile Node Identifier option [RFC5213].
The offload policy MUST be specific to a mobile node's
application traffic. The traffic selectors have to match only
the mobile node's application traffic and MUST NOT match any
other mobile node's IP traffic. Furthermore, control plane control-plane
traffic such as DHCP, ND Neighbor Discovery (ND), or any other IP
traffic that is used for IP address configuration, mobility management
management, or for other
control plane control-plane functions has to MUST NOT be excluded.
subject to offload.

* The local mobility anchor MUST NOT make any changes to the
mobile node's offload policy during the middle of a mobility
session, as long as the mobile node continues to attach to the
mobile access gateway that might break some of negotiated the offload policy.
However, when the mobile node performs an inter-MAG handover,
the new mobile access gateway may not be capable of supporting
IP sessions.
Therefore Traffic offload and in this scenario, the offload policy may
change. Therefore, the IPv4 Traffic Selector option with the
Traffic Selector sub-option that is delivered during the
initial mobility signaling signaling MUST be the same as the one that is
delivered as part of the mobility signaling related to lifetime extension.
extension from the same mobile access gateway.

4. Protocol Configuration Variables

This specification defines the following configuration variable that
controls the IPv4 Traffic Offload traffic offload support feature. This
configuration variable is internal to the system and has no bearing
on interoperability across different implementations.

The mobility entities, local mobility anchor anchor, and the mobile access
gateway have to allow these variables to be configured by the system
management. The configured values for these protocol variables have
to survive server reboots and service restarts.

EnableIPv4TrafficOffloadSupport

This flag indicates whether or not IPv4 Traffic Offload traffic offload support
needs to be enabled. This configuration variable is available
at both in the mobile access gateway and at the local mobility
anchor. The default value for this flag is set to (0),
indicating that the support for IPv4 Traffic traffic offload support is disabled.

When this flag on the mobile access gateway is set to a value
of (1), the mobile access gateway has to enable the IPv4
Traffic traffic
offload support for all mobility sessions, by specifically
request
requesting the IPv4 traffic offload policy from the local
mobility anchor by including the IPv4 Traffic Offload Selector
option in the Proxy Binding Update message. If the flag is set
to a value of (0), the mobile access gateway has to disable support
for
IPv4 Traffic Offload traffic offload support for all mobility sessions.

Similarly, when this flag on the local mobility anchor is set
to a value of (1), the local mobility anchor has to enable
support for IPv4 Traffic
traffic offload support. When If the local mobility anchor chooses
to enable IPv4 Traffic traffic offload support
and if when there is an offload
policy specified for a mobile node, it has to deliver the IPv4
traffic offload policy to the mobile access gateway by
including the IPv4 Traffic Offload Selector option in the Proxy
Binding Acknowledgement message.

5. IANA Considerations

This document requires the following

Per this specification, IANA action.

o Action-1: This specification defines has assigned a new mobility option, option: the
IPv4 Traffic Offload Selector option. option (53). This option is described
in Section 3.1. The Type value for this option needs to be has been assigned
from the same numbering space as allocated for the other mobility
options [RFC6275].

o RFC Editor: Please replace <IANA-1> in Section 4 with the assigned
value, and update this section accordingly.

6. Security Considerations

The IPv4 Traffic Offload Selector option defined in this
specification is for use in Proxy Binding Update and Proxy Binding
Acknowledgement messages. This option is carried like any other
mobility header option as specified in [RFC5213]. Therefore Therefore, it
inherits from [RFC5213] its security guidelines and does not require
any additional security considerations. Carrying IPv4 traffic
offload selectors does not introduce any new security
vulnerabilities.

When IPv4 traffic offload support is enabled for a mobile node, the
mobile access gateway selectively offloads some of the mobile node's
IPv4 traffic flows to the access network. Typically, these offloaded
flows get NAT translated and translated, which essentially that introduces certain
vulnerabilities which that are common to any NAT deployment. These
vulnerabilities and the related considerations have been well
documented in the NAT specification [RFC2663]. There are no
additional considerations above and beyond what has already been
documented by the NAT specifications and which that are unique to the
approach specified in this document.

The mobile node's home network may be equipped with firewall and
other security devices to guard against any security threats. When
IPv4 traffic offload support is enabled, it potentially exposes the
mobile node to some security risks in the access network. This
threat can be mitigated by deploying the security features both in
the access network as and in the home network.

When IPv4 traffic offload support is enabled for a mobile node, some
of the IP flows are sent through the home network network, and some other IP
flows are routed through the access network. This potentially
introduces some complexity with respect to enabling diagnostics or
monitoring on the user traffic. The tools that are used for such
diagnostics have to be aware of the offload policy that in enabled in
the network.

7. Acknowledgements

The authors would like to thank Ahmad Muhanna, Basavaraj Patil,
Carlos Bernardos, Eric Voit, Frank Brockners, Hidetoshi Yokota, Marco
Liebsch, Mark Grayson, Pierrick Seite, Ryuji Wakikawa, Steve Wood,
Barry Lieba, Leiba, Sean Turner, Pete Resnick, Wesley Eddy, Mary Barnes,
Vincent Roca, Ralph Droms, Scott Bradner, Stephen Farrell, Adrian
Farrell,
Farrel, Benoit Claise Claise, and Brian Haberman for all the draft reviews and
discussions related to the topic of IPv4 traffic offload.

8. References

8.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.

[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
Mobile IPv6", RFC 5844, May 2010.

[RFC6088] Tsirtsis, G., Giarreta, G., Soliman, H., and N. Montavont,
"Traffic Selectors for Flow Bindings", RFC 6088,
January 2011.

[RFC6089] Tsirtsis, G., Soliman, H., Montavont, N., Giaretta, G.,
and K. Kuladinithi, "Flow Bindings in Mobile IPv6 and
Network Mobility (NEMO) Basic Support", RFC 6089,
January 2011.

[RFC6275] Perkins, C., Johnson, D., and J. Arkko, "Mobility Support
in IPv6", RFC 6275, July 2011.

8.2. Informative References

[RFC2663] Srisuresh, P. and M. Holdrege, "IP Network Address
Translator (NAT) Terminology and Considerations",
RFC 2663, August 1999.

[RFC5101] Claise, B., "Specification of the IP Flow Information
Export (IPFIX) Protocol for the Exchange of IP Traffic
Flow Information", RFC 5101, January 2008.

[TS23402] 3GPP, "Architecture enhancements for non-3GPP accesses",
2010.

Authors' Addresses

Sri Gundavelli (editor)
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA

Email:

EMail: sgundave@cisco.com

Xingyue Zhou
ZTE Corporation
No.68 Zijinghua Rd
Nanjing
China

Email:

EMail: zhou.xingyue@zte.com.cn

Jouni Korhonen
Nokia Siemens Networks
Linnoitustie 6
Espoo FIN-02600
Renesas Mobile
Porkkalankatu 24
Helsinki FIN-00180
Finland

Email:

EMail: jouni.nospam@gmail.com

Gaetan Feige
Cisco
France

Email:

EMail: gfeige@cisco.com

Rajeev Koodli
Cisco
3650 Cisco Way
San Jose, CA 95134
USA

Email:

EMail: rkoodli@cisco.com