DMM WG P. Seite
Internet-Draft Orange
Intended status: Standards Track A. Yegin
Expires: December 27, 2015 Samsung
S. Gundavelli
Cisco
June 25, 2015
Multihoming support for Residential Gateways
draft-seite-dmm-rg-multihoming-01.txt
Abstract
The Quality-of-Experience of a fixed-network user can be
significantly improved by enabling the Residential Gateway (RG)
providing IP connectivity services to connect to the internet through
multiple access networks (Example: LTE and DSL) and use all the
available network bandwidth for the user traffic. This approach
enables a service provider to leverage all the availble access
networks and to offer guaranteed Quality-of-Service to the end-user
on any application basis. Furthermore, the mobility functions in the
residential gateway and in the service provider network will be able
to monitor the performance of all the access paths and dynamically
change the routing path for an application. This document
investigates the use of IP mobility protocols for supporting this
use-case and it also identifies the needed protocol extensions.
Status of this Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on December 27, 2015.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
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document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
3. Use-cases . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Architectures and requirements . . . . . . . . . . . . . . . . 5
4.1. Architectures . . . . . . . . . . . . . . . . . . . . . . 5
4.2. Traffic distribution schemes . . . . . . . . . . . . . . . 8
4.3. Tunnelling . . . . . . . . . . . . . . . . . . . . . . . . 9
5. Solution Overview - PMIPv6 Approach . . . . . . . . . . . . . 9
5.1. Protocol Extensions . . . . . . . . . . . . . . . . . . . 10
5.1.1. MAG Multipath-Binding Option . . . . . . . . . . . . . 10
5.1.2. MAG Identifier Option . . . . . . . . . . . . . . . . 12
5.1.3. New Status Code for Proxy Binding Acknowledgement . . 13
5.2. Call Flows . . . . . . . . . . . . . . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 15
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
9.1. Normative References . . . . . . . . . . . . . . . . . . . 15
9.2. Informative References . . . . . . . . . . . . . . . . . . 16
Appendix A. Appendix A . . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
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1. Introduction
Fixed access networks (e.g. DSL) usually provides Internet
connectivity via a Residential Gateway (RG) acting as the access
router. When equipped with different Wide Area Network (WAN) access
technologies (e.g. DSL and LTE), the RG could take benefit of
multihoming advantages such as redundancy, load balancing, load
sharing and so on. Besides, the Broadband Forum (BBF) has recently
initiated a new standardization effort, "Hybrid Access for Broadband
Networks" [WT-348] to address this use-case. The multihomed RG use-
case has been identified as an IP mobility scenario for a while
[RFC4908]. In a fix network context, like in the "Hybrid Access for
Broadband Networks" scenario, IP mobility protocols are obviously not
used to manage user mobility, but for their subscriber and traffic
management capabilities (e.g. move IP traffic between WAN interfaces
while maintaining IP session continuity). Moreover, the hybrid
access system can take benefit from the policy routing (i.e. IP flow
routing policies) capability of the IP mobility protocols.
This document refreshes [RFC4908] by describing how to use the IP
mobility protocols (e.g. [RFC3753], [RFC6275] and [RFC5213]) and
their extensions (e.g. Multiple care-of-address [RFC5648], IP flow
mobility [RFC6089])to address the Hybrid Access issue. The usual IP
mobility protocols operations allows sharing WAN interfaces on an IP
flow basis: a multihomed RG uses simultaneously more that one WAN
interface (e.g. DSL and LTE) and each IP flow is bounded to one of
the available interfaces, as per IP flow mobility use-case [RFC6089].
"Hybrid access" use-case is also expected to operate on a IP packet
basis: packets of a single IP flow are distributed over more than one
WAN interface, i.e. the system performs WAN interfaces bonding to
provide higher WAN bandwidth to a single IP flow. Although interface
bonding differs from the usual IP mobility operations, this document
addresses this use-case as well. Actually, IP mobility protocols
allow to establish and maintain the forwarding plane in user, of
flow, mobility situation (i.e. using IP tunnels); but nothing prevent
to use this data plane on a per packet basis. It must be noted that
this traffic distribution scheme may raise tricky packet reordering
and buffering issues. However, addressing these issues is out the
scope of this document. At last, this document identifies new
mobility options that would be necessary to address some of the
hybrid access use-case.
Document requires additional updates and efforts are in progress.
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Flow-1
|
|Flow-2 _----_
| | CoA-1 _( )_ Tunnel-1
| | .---=======( LTE )========\ Flow-1
| | | (_ _) \Flow-4
| | | '----' \
| | +=====+ \ +=====+ _----_
| '-| | \ | | _( )_
'---| CPE | | BNG |-( Internet )--
.---| | | | (_ _)
| .-| | / | | '----'
| | +=====+ / +=====+
| | | _----_ /
| | | CoA-2 _( )_ Tunnel-2 /
| | .---=======( DSL )========/ Flow-2
| | (_ _) Flow-3
| | '----'
|Flow-3
|
Flow0=-4
Figure 1: Hybrid-Access With IP mobility prorocols
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 mobility related terms used in this document are to be
interpreted as defined in [RFC5213], [RFC5844] and [RFC7148].
Additionally, this document uses the following terms:
IP-in-IP
IP-within-IP encapsulation [RFC2473], [RFC4213]
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3. Use-cases
The current evolution of the Internet usage makes users more and more
greedy of high throughput services (e.g. video streaming, file
downloading, peer-to-peer,....). However, upgrading the fix access,
to meet resulting high bandwidth demand, is sometimes difficult; for
example in historic cities downtown where only Internet access based
on old copper line is deployed. At the same time, these areas may be
within LTE coverage from which the user could benefit to access the
Internet services. In this situation "Hybrid access for Broadband
Networks" system, using a multiple WAN interfaces RG, may come into
play with the two following use-cases:
Load balancing: the hybrid access system uses simultaneously all
the available WAN interfaces and binds each application on one of
these interface, i.e. increase WAN bandwidth from the user
standpoint. The system must be able to identify traffic (e.g.
issued from a specific user, or terminal; or an application) and,
depending on its characteristics (e.g. QoS requirements),
forwards it on the most appropriate WAN interface.
Load sharing: The hybrid access allows the user to get access to
higher throughput services (e.g. IPTV). The RG is equipped with
and combines them to get additional WAN resources and provide
higher bandwidth per application.
4. Architectures and requirements
4.1. Architectures
Figure 2 depicts the architecture for hybrid access use-cases relying
on multiple WAN interfaces Residential Gateway. WAN interfaces can
be either physical (e.g. DSL, LTE) or virtual (e.g. VLAN). On the
network side, an aggregation gateway is in charge to distribute the
downlink traffic to the different WAN paths. Uplink traffic
management depends on the traffic distribution scheme (see
Section 4.2); it is detailed in section . In this architecture, the
RG can be viewed as a mobile router, or mobile node, (so, supporting
mobility management client) managing multiple local interfaces, i.e.
multiple care-of-addresses. IP mobility protocols (e.g. NEMO
[RFC3963]), together with Multiple Care-of-Address [RFC5648]), can
thus be used to establish dynamically the forwarding paths between
the RG and the IP the aggregation gateway, so playing a mobility
anchor role.
The RG obtains local IP addresses, i.e. care-of-address, via legacy
IP allocation mechanisms (e.g. DHCP, SLAAC) of the WAN interfaces.
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Then, in order to set-up data path up to the aggregation gateway
(i.e. mobility anchor), the RG uses the multiple care-of-addresses
[RFC5648] mobility option to registers these care-of-addresses to the
mobility anchor. Bi-directional IP tunnels are established, between
the RG and the mobility anchor, over each WAN interface. The
mobility anchor provision the RG with a unique IP address, i.e. Home
Prefix/Address, through which the RG is reachable from then Internet.
When the Home Agent receives a data packet meant for a node in the RG
Network, it tunnels the packet to the RG to one of the available
care-of address. The selection of the care-of-address depends on the
traffic distribution scheme, operating either on a IP flow or on
packet basis (see Section 4.2).
IP Network #1
(e.g. DSL)
+------------+ _--------_ +------------+
| | ( ) | |
|Residential +======(==IP-in-IP==)==+ |
| Gateway | (_ _) |Aggregation |
| (RG) | (_______) | Gateway |
| | |(Home Agent)|------>
| Mobility | | |
| Client | | |
| | _--------_ | |
| | ( ) | |
| +======(==IP-in-IP==)==+ |
| | (_ _) | |
+-----+------+ (______) +------------+
| IP Network #2
----RG network---- (eg. LTE)
|
end-nodes
Figure 2: Multihomed RG architecture
Depending on the deployment architecture, the hybrid access
management may be not supported by the RG. For example, in Figure 3,
DSL and LTE networks are operated by two different operators and the
hybrid access service is provided by the mobile operator.
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DSL access
+------------+ _--------_ +------------+
| | ( ) | |
|Residential +======(==IP-in-IP==)==+ |
| Gateway | (_ _) |Aggregation |
+------------+ (_______) | Gateway |
| |(Home Agent)|------>
WLAN (RG network) | |
| LTE Access | |
+------------+ _--------_ | |
| | ( ) | |
| Mobility +======(==IP-in-IP==)==+ |
| Client | (_ _) | |
+-----+------+ (______) +------------+
|
Hybrid access network
|
end-nodes
Figure 3: split RG and hybrid access management
As a, alternative to NEMO [RFC3963]), Proxy Mobile IPv6 [RFC5648] can
also be used to provide, in addition, IP session continuity when a
mobile node moves between the cellular network to the home network
between RG, or between access router (e.g. RG). In Proxy Mobile
IPv6 architecture, the access router supporting mobility management
functions is called a Mobile Access Gateway (MAG). Being
functionally similar to the RG, the MAG could take benefit from the
hybrid access advantages. To do so, the MAG must be able to manage
multiple care-of-addresses as depicted in Figure 4.
+------------+
+------------+ | |
| +==PMIP Tunnel / DSL===+ |
| MAG #1 | | |
| +==PMIP tunnel / LTE===+ |
+------------+ | LMA |
| | |
MN#2| -------- | |------>
| MN#1-( LTE )===========| |
| | ( ) | |
V V -------- | |
+------------+ | |
| +==PMIP Tunnel / DSL===+ |
| MAG #2 | | |
| +==PMIP tunnel / LTE===+ |
+------------+ +------------+
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Figure 4: Multihomed MAG for PMIP
4.2. Traffic distribution schemes
IP mobility protocols allow to establish the forwarding plane over
the WAN interfaces of a multihomed RG. Then, traffic distribution
schemes define the way to distribute data packets over these paths
(i.e. IP tunnels). Traffic distribution can be managed either on a
per-flow or on a per-packet basis:
o per-flow traffic management: each IP flow (both upstream and
downstream) is mapped to a given mobile IP tunnel, corresponding
to a given WAN interface. This scenario is based on IP flow
mobility mechanism using the Flow binding extension [RFC6089].
The mobility anchor provides IP session continuity when an IP flow
is moved from one WAN interfaces to another. The flow binding
extension allows the IP mobility anchor and the RG to exchange,
and synchronize, IP flow management policies (i.e. policy routing
rules associating traffic selectors [RFC6088] to mobility
bindings).
o Per-packet management: distribute the IP packets of a same IP
flow, or of a group of IP flows, over more than one WAN interface.
In this scenario, traffic management slightly differs from the
default mobile IP behaviour; the mobility entities (mobility
anchor and client) distribute packets, belonging to a same IP
flow, over more than one bindings simultaneously. The definition
of control algorithm of a Per-packet distribution scheme (how to
distribute packets) is out the scope of this document. When
operating at the packet level, traffic distribution scheme may
introduce packet latency and out-of-order delivery. It may
require the aggeregation entities (RG and mobility anchor) to be
able to reorder (ans thus, to buffer) received packets before
delivering. A possible implementation is to use GRE as mobile
tunnelling mechanism, together with the GRE KEY option [RFC5845]
to add sequence number to GRE packets, and so, to allow the
receiver to perform reordering. However, more detailed buffering
and reordering considerations are out of the scope of this
document.
The traffic distribution scheme may require the RG and the to
exchange interface metrics to make traffic steering decision.For
example, the RG may sent its DSL synchronization rate to the mobility
anchor, so that the latter can make traffic forwarding decision
accordingly. In this case, the vendor specific mobility option
[RFC5094] can be used for that purpose (see example in apapendix
Appendix A).
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Per-flow and per-packet distribution schemes are not exclusive
mechanisms; they can cohabit in the same hybrid access system. For
example, High throughput services (e.g. video streaming) may benefit
from per-packet distribution scheme, while some other may not.
Typically VoIP application are sensitive to latency and thus should
not be split over different WAN paths. In this situation, the
aggregation entities (RG and mobility anchor) must exchange traffic
management policies to associate distribution scheme, traffic and WAN
interface (physical or virtual). [RFC6088] and [RFC6089] define
traffic management on a flow basis but there is no such policy on a
per packet basis.
4.3. Tunnelling
The hybrid access system should be able to support multiple type of
tunnelling mechanisms:
o IP-in-IP: default IP mobility tunnelling mechanism.
o GRE: the GRE KEY option can allow to manage packet reordering
o GTP: Network based mobility management of the 3GPP cellular
networks use GTP as tunnelling mechanism.
o IPsec
5. Solution Overview - PMIPv6 Approach
Below protocols considerations also apply to both PMIPv6 and NEMO.
However for the sake of simplicicity, this section focuses on a
PMIPv6 based hybrid access system. In such an implementation, the
the MAG functionality is enabled on the CPE and the LMA functionality
is enabled on the agregation gateway inside the SP network.
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_----_
CoA-1 _( )_ Tunnel-1
.---=======( LTE )========\ Flow-1
| (_ _) \Flow-4
| '----' \
+=====+ \ +=====+ _----_
| | \ | | _( )_
| MAG | | LMA |-( Internet )--
.---| | | | (_ _)
| |(CPE)| / | | '----'
| +=====+ / +=====+
| | _----_ /
| | CoA-2 _( )_ Tunnel-2 /
| .---=======( Fixed )========/ Flow-2
| (_ _) Flow-3
| '----'
|
[MN]
Figure 5: Hybrid-Access With PMIPv6
5.1. Protocol Extensions
5.1.1. MAG Multipath-Binding Option
The MAG Multipath-Binding option is a new mobility header option
defined for use with Proxy Binding Update and Proxy Binding
Acknowledgement messages exchanged between the local mobility anchor
and the mobile access gateway.
This mobility header option is used for requesting multipath support.
It indicates that the mobile access gateway is requesting the local
mobility anchor to register the current care-of address associated
with the request as one of the many care-addresses through which the
mobile access gateway can be reached. It is also for carrying the
information related to the access network associated with the care-of
address.
The MAG Multipath-Binding option has an alignment requirement of
8n+2. Its format is as shown in Figure 6:
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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 | If-ATT | If-Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Binding-Id |B|O| RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: MAG Multipath Binding Option
Type
<IANA-1> To be assigned by IANA.
Length
8-bit unsigned integer indicating the length of the option in
octets, excluding the type and length fields.
This 8-bit field identifies the Access-Technology type of the
interface through which the mobile node is connected. The permitted
values for this are from the Access Technology Type registry defined
in [RFC5213].
This 8-bit field represents the interface label represented as an
unsigned integer. The mobile node identifies the label for each of
the interfaces through which it registers a CoA with the home agent.
When using static traffic flow policies on the mobile node and the
home agent, the label can be used for generating forwarding policies.
For example, the operator may have policy which binds traffic for
Application "X" needs to interface with Label "Y". When a
registration through an interface matching Label "Y" gets activated,
the home agent and the mobile node can dynamically generate a
forwarding policy for forwarding traffic for Application "X" through
mobile IP tunnel matching Label "Y". Both the home agent and the
mobile node can route the Application-X traffic through that
interface. The permitted values for If-Label are 1 through 255.
This 8-bit field is used for carrying the binding identifier. It
uniquely identifies a specific binding of the mobile node, to which
this request can be associated. Each binding identifier is
represented as an unsigned integer. The permitted values are 1
through 254. The BID value of 0 and 255 are reserved. The mobile
access gateway assigns a unique value for each of its interfaces and
includes them in the message.
This flag, if set to a value of (1), is to notify the local mobility
anchor to consider this request as a request to update the binding
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lifetime of all the mobile node's bindings, upon accepting this
specific request. This flag MUST NOT be set to a value of (1), if
the value of the Registration Overwrite Flag (O) flag is set to a
value of (1).
This flag, if set to a value of (1), notifies the local mobility
anchor that upon accepting this request, it should replace all of the
mobile node's existing bindings with this binding. This flag MUST
NOT be set to a value of (1), if the value of the Bulk Re-
registration Flag (B) is set to a value of (1). This flag MUST be
set to a value of (0), in de-registration requests.
Reserved
This field is unused in this specification. The value MUST be set
to zero (0) by the sender and MUST be ignored by the receiver.
5.1.2. MAG Identifier Option
The MAG Identifier option is a
This option does not have any alignment requirements.
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 | Subtype | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: MAG Identifier Option
Type
<IANA-2> To be assigned by IANA.
Length
8-bit unsigned integer indicating the length of the option in
octets, excluding the type and length fields.
Subtype
One byte unsigned integer used for identifying the type of the
Identifier field. Accepted values for this field are the
registered type values from the Mobile Node Identifier Option
Subtypes registry.
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Reserved
This field is unused in this specification. The value MUST be set
to zero (0) by the sender and MUST be ignored by the receiver.
Identifier
A variable length identifier of type indicated in the Subtype
field.
5.1.3. New Status Code for Proxy Binding Acknowledgement
This document defines the following new Status Code value for use in
Proxy Binding Acknowledgement message.
CANNOT_SUPPORT_MULTIPATH_BINDING (Cannot Support Multipath Binding):
<IANA-4>
5.2. Call Flows
Figure 8 is the callflow detailing hybrid access support with PMIPv6.
The CPE in this example scenario is equipped with both WLAN and LTE
interfaces and is also configured with the MAG functionality. A
logical-NAI with ALWAYS-ON configuration is enabled on the MAG. The
mobility session that is created on the LMA is for the logical-NAI.
The IP hosts MN_1 and MN_2 are assigned IP addresses from the
delegated mobile network prefix.
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+=====+ +=====+ +=====+ +=====+ +=====+ +=====+
| MN_1| | MN_2| | MAG | | WLAN| | LTE | | LMA |
+=====+ +=====+ +=====+ +=====+ +=====+ +=====+
| | | | | |
| | | | | |
| | | (1) ATTACH | | |
| | | <--------> | | |
| | | (2) ATTACH | |
| | | <---------------------->| |
| | | (3) PBU (NAI, MAG-NAI, DMNP, MMB) |
| | | ------------------------*----------> |
| | | (4) PBA (NAI, DMNP) |
| | | <-----------------------*----------- |
| | | (5) TUNNEL INTERFACE CREATION |
| | |-============== TUNNEL ==*===========-|
| | | |
| | | (6) PBU (NAI, MAG-NAI, DMNP, MMB) |
| | | -----------*-----------------------> |
| | | (7) PBA (NAI, DMNP) |
| | | <----------*------------------------ |
| | | (8) TUNNEL INTERFACE CREATION |
| | |-===========*== TUNNEL ==============-|
| (9) | |
| <------------------> | |
| | (10) | |
| |<-----------> | |
Figure 8: Functional Separation of the Control and User Plane
6. IANA Considerations
This document requires the following IANA actions.
o Action-1: This specification defines a new mobility option, the
MAG Multipath-Binding option. The format of this option is
described in Section 5.1.1. The type value <IANA-1> for this
mobility option needs to be allocated from the Mobility Options
registry at <http://www.iana.org/assignments/mobility-parameters>.
RFC Editor: Please replace <IANA-1> in Section 5.1.1 with the
assigned value and update this section accordingly.
o Action-2: This specification defines a new mobility option, the
MAG Identifier option. The format of this option is described in
Section 5.1.2. The type value <IANA-2> for this mobility option
needs to be allocated from the Mobility Options registry at
<http://www.iana.org/assignments/mobility-parameters>. RFC
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Editor: Please replace <IANA-2> in Section 5.1.2 with the assigned
value and update this section accordingly.
o Action-4: This document defines a new status value,
CANNOT_SUPPORT_MULTIPATH_BINDING (<IANA-4>) for use in Proxy
Binding Acknowledgement message, as described in Section 5.1.3.
This value is to be assigned from the "Status Codes" registry at
<http://www.iana.org/assignments/mobility-parameters>. The
allocated value has to be greater than 127. RFC Editor: Please
replace <IANA-4> in Section 5.1.3 with the assigned value and
update this section accordingly.
7. Security Considerations
This specification allows a mobile access gateway to establish
multiple Proxy Mobile IPv6 tunnels with a local mobility anchor, by
registering a care-of address for each of its connected access
networks. This essentially allows the mobile node's IP traffic to be
routed through any of the tunnel paths and either based on a static
or a dynamically negotiated flow policy. This new capability has no
impact on the protocol security. Furthermore, this specification
defines two new mobility header options, MAG Multipath-Binding option
and the MAG Identifier option. These options are carried like any
other mobility header option as specified in [RFC5213]. Therefore,
it inherits security guidelines from [RFC5213]. Thus, this
specification does not weaken the security of Proxy Mobile IPv6
Protocol, and does not introduce any new security vulnerabilities.
8. Acknowledgements
The authors of this draft would like to acknowledge the discussions
and feedback on this topic from the members of the Broadband Forum.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3963] Devarapalli, V., Wakikawa, R., Petrescu, A., and P.
Thubert, "Network Mobility (NEMO) Basic Support Protocol",
RFC 3963, January 2005.
[RFC5094] Devarapalli, V., Patel, A., and K. Leung, "Mobile IPv6
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Vendor Specific Option", RFC 5094, December 2007.
[RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.
[RFC5648] Wakikawa, R., Devarapalli, V., Tsirtsis, G., Ernst, T.,
and K. Nagami, "Multiple Care-of Addresses Registration",
RFC 5648, October 2009.
[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
Mobile IPv6", RFC 5844, May 2010.
[RFC5845] Muhanna, A., Khalil, M., Gundavelli, S., and K. Leung,
"Generic Routing Encapsulation (GRE) Key Option for Proxy
Mobile IPv6", RFC 5845, June 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.
[RFC7148] Zhou, X., Korhonen, J., Williams, C., Gundavelli, S., and
CJ. Bernardos, "Prefix Delegation Support for Proxy Mobile
IPv6", RFC 7148, March 2014.
9.2. Informative References
[RFC2473] Conta, A. and S. Deering, "Generic Packet Tunneling in
IPv6 Specification", RFC 2473, December 1998.
[RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology",
RFC 3753, June 2004.
[RFC4213] Nordmark, E. and R. Gilligan, "Basic Transition Mechanisms
for IPv6 Hosts and Routers", RFC 4213, October 2005.
[RFC4908] Nagami, K., Uda, S., Ogashiwa, N., Esaki, H., Wakikawa,
R., and H. Ohnishi, "Multi-homing for small scale fixed
network Using Mobile IP and NEMO", RFC 4908, June 2007.
[WT-348] "Liaison Statement: Broadband Forum Work on "Hybrid Access
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Internet-Draft Multihoming support for RG June 2015
for Broadband Networks" (WT-348)", BBF Broadband Forum,
October 2014, <http://datatracker.ietf.org/liaison/1355/>.
Appendix A. Appendix A
The traffic distribution scheme may require the RG and the HRG and
HAG to exchange interface metrics to make traffic steering decision.
For example, the RG may send its DSL synchronization rate to the
mobility anchor, so that the latter can make traffic forwarding
decision accordingly. In this case, the vendor specific mobility
option [RFC5094] can be used.
The << Mobile IPv6 Vendor Specific Option >> can be used with the
broadband forum Vendor ID (3561). This option in piggybacked by
control messages exchanged between CPE and the Aggregation Gateway
(e.g. Binding Update, Binding Update ACK).
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Vendor ID = 3561 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Type | Data....... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: Vendor Specific Option
Sub-Type identifies Hybrid access specific information. The
administration of the Sub-type should be done by the BBF. Any type
of information can be supported, it can be information related to
access networks (LTE, DSL) or information related to services (e.g.
IPTV throughput). For example, the following defines an hybrid
access sub-option to allow the CPE sending its DSL synchronisation
rate to the Aggregation Gateway.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Type = 1 | Length = 4 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DSL synchronisation rate (bps) |
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: Vendor Specific Option - Sub-Type
Length: An 8-bit field indicating the length of the option in
octets excluding the sub-Type and the Length fields. Here, Length
= 4.
Sub-Type : indicating that BBF information is the DSL sync rate.
Here, Sub-Type = 1.
Authors' Addresses
Pierrick Seite
Orange
4, rue du Clos Courtel, BP 91226
Cesson-Sevigne 35512
France
Email: pierrick.seite@orange.com
Alper Yegin
Samsung
Istanbul
Turkey
Email: alper.yegin@partner.samsung.com
Sri Gundavelli
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
Email: sgundave@cisco.com
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