Internet DRAFT - draft-ietf-mip4-multiple-tunnel-support
draft-ietf-mip4-multiple-tunnel-support
Mobility for IPv4 Working Group S. Gundavelli, Ed.
Internet-Draft K. Leung
Intended status: Experimental Cisco
Expires: December 23, 2015 G. Tsirtsis
Qualcomm
A. Petrescu
CEA LIST
June 21, 2015
Flow Binding Support for Mobile IP
draft-ietf-mip4-multiple-tunnel-support-13.txt
Abstract
This specification defines extensions to Mobile IP protocol for
allowing a mobile node with multiple interfaces to register a care-of
address for each of its network interfaces and to simultaneously
establish multiple IP tunnels with its home agent. This essentially
allows the mobile node to utilize all the available network
interfaces and build an higher aggregated logical pipe with its home
agent for its home address traffic. Furthermore, these extensions
also allow the mobile node and the home agent to negotiate IP traffic
flow policies for binding individual flows with the registered
care-of addresses.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 23, 2015.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 3
2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Example Call Flow . . . . . . . . . . . . . . . . . . . . 6
4. Message Extensions . . . . . . . . . . . . . . . . . . . . . . 7
4.1. Multipath Extension . . . . . . . . . . . . . . . . . . . 7
4.2. Flow-Binding Extension . . . . . . . . . . . . . . . . . . 9
4.3. New Error Codes for Registration Reply . . . . . . . . . . 12
5. Protocol Operation . . . . . . . . . . . . . . . . . . . . . . 12
5.1. Mobile Node Considerations . . . . . . . . . . . . . . . . 12
5.2. Home Agent Considerations . . . . . . . . . . . . . . . . 14
6. Routing Considerations . . . . . . . . . . . . . . . . . . . . 14
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 16
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 17
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
11.1. Normative References . . . . . . . . . . . . . . . . . . . 17
11.2. Informative References . . . . . . . . . . . . . . . . . . 17
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1. Introduction
With the ubiquitous availability of wireless networks based on
different access technology types, mobile devices are now equipped
with multiple wireless interfaces and have the ability to connect to
the network using any of those interfaces. For example, most mobile
devices are equipped with Wi-Fi and LTE interfaces. In many
deployments, it is desirable for a mobile node to leverage all the
available network interfaces and have IP mobility support for its IP
flows.
The operation defined in the Mobile IP Protocol [RFC5944], allows a
mobile node to continue to use its home address as it moves around
the internet. Based on the mode of operation, there will be a IP
tunnel that will be established between the home agent [RFC5944] and
the mobile node [RFC5944], or between the home agent and the foreign
agent [RFC5944] where the mobile node is attached. In both of these
modes, there will only be one interface on the mobile node that is
receiving the IP traffic from the home agent. This approach of using
a single access-interface for routing all mobile node's traffic is
not efficient and so there is a need to extend Mobile IP to
concurrently use multiple access-interfaces for routing the mobile
node's IP traffic. The goal is for efficient use of all the
available access links to obtain higher aggregated bandwidth for the
tunneled traffic between the home agent and the mobile node.
This specification defines extensions to Mobile IPv4 protocol for
allowing a mobile node with multiple interfaces to register a care-of
address for each of its network interfaces and to simultaneously
leverage all access links for the mobile node's IP traffic.
Furthermore, this specification also defines extensions to allow the
mobile node and the home agent to optionally negotiate IP flow
policies for binding individual IP flows with the registered care-of
addresses.
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 terms used in this document are to be
interpreted as defined in [RFC5944] and [RFC3753]. In addition this
document uses the following terms.
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Binding Identifier (BID)
It is an identifier assigned to a mobile node's binding. A
binding defines an association between a mobile node's home
address and its registered care-of address. When a mobile node
registers multiple bindings with its home agent, each using a
different care-of address, then each of those bindings are given a
unique identifier. Each of the binding identifier will have a
unique value which will be different from the identifiers assigned
to the mobile node's other bindings.
Flow Identifier (FID)
It is an identifier for a given IP flow, uniquely identified by
source address, destination address, protocol type, source port,
destination port, Security Parameter Index and other parameters as
identified in [RFC6088]. In the context of this document, the IP
flows associated with a mobile node are the IP flows using its
home address. For a mobile router, the IP flows also include the
IP flows using the mobile network prefix [RFC6626].
3. Overview
The illustration below in Figure 1 is an example scenario where a
mobile node is connected to WLAN, LTE and CDMA access networks. The
mobile node is configured with an home address, HoA_1, and has
obtained the care-of addresses [RFC5944] CoA_1 from the WLAN network,
CoA_2 from the LTE network and CoA_3 from the CDMA network.
The mobile node using the extensions specified in this document
registers all the three care-of addresses with its home agent. The
mobile node also establishes an IP tunnel with the home agent using
each of its IP addresses; Resulting in three IP tunnels (Tunnel_1,
Tunnel_2 and Tunnel_3) between the mobile node and the home agent.
Each of the tunnel represents a overlay routing path between the
mobile node and the home agent and can be used for forwarding the
mobile node's IP traffic.
Furthermore, the extensions specified in this document allow the
mobile node and the home agent to negotiate a IP flow policy. The
negotiated flow policy allow the mobile node and the home agent in
determining the access network path for each of the mobile node's IP
flows.
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Flow_1 (SIP)
|
|Flow_2 (SSH)
| |
| |Flow_3 (HTTP) _----_
| | | CoA_1 _( )_ Tunnel_1
| | | .---=======( Wi-Fi )========\ Flow_1
| | | | (_ _) \
| | | | '----' \
| | | +=====+ _----_ \ +=====+ _----_
| | '-| | CoA_2 _( )_ Tunnel_2 \ | | _( )_ --
| '---| MN |---====( LTE )=========-----| HA |-( internet )--
'-----| | (_ _) Flow_3 / | | (_ _) --
+=====+ '----' / +=====+ '----'
| | _----_ /
HoA_1--' | CoA_3 _( )_ Tunnel_3 /
.------====( CDMA )========/ Flow_2
(_ _)
'----'
Figure 1: Mobile Node with multiple tunnels to the home agent
The above table is an example of how the individual flows are bound
to different care-of addresses registered with the home agent.
+=========+===================+=====================================+
| Flow Id | Access Network | Description |
| (FID) | Preferences | |
+=========+===================+=====================================+
| Flow_1 | Tunnel_1 / CoA_1 | All SIP Flows over Wi-Fi (preferred)|
| | Tunnel_2 / CoA_2 | If Wi-Fi is not available, use LTE |
| | <DROP> | If Wi-Fi and LTE access network are |
| | | not available, drop the flow |
+---------+-------------------+-------------------------------------+
| Flow_3 | Tunnel_2 / CoA_2 | All HTTP Flows over LTE (Preferred) |
| | <DROP> | If LTE not available, drop the flow |
+---------+-------------------+-------------------------------------+
| Flow_2 | Tunnel_3 / CoA_3 | All SSH Flows over CDMA (Preferred) |
| | Tunnel_2 / CoA_2 | If CDMA not available, use LTE |
| | Tunnel_1 / CoA_1 | If LTE not available, use Wi-Fi |
+---------+-------------------+-------------------------------------+
Figure 2: Example of a IP Traffic Policy
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3.1. Example Call Flow
Figure 3 is the call-flow for the example scenario where a mobile
node is connected to WLAN and LTE access networks.
+-------+ +-------+ +-------+ +-------+
| MN | | WLAN | | LTE | | HA |
| | |Network| |Network| | |
+-------+ +-------+ +-------+ +-------+
| | | |
* MIP RRQ is sent using the IP Address obtained from the WLAN Network
|<--- (1) --------->| | |
| | RRQ (Multipath, Flow-Binding) |
|---- (2) ----------------------------------------------->|
| | RRP | |
|<--- (3) ------------------------------------------------|
| MIP Tunnel through WLAN Network |
|=====(4)===========*=====================================|
* MIP RRQ is sent using the IP address obtained from the LTE Network
|<--- (5) ---------------------------->| |
| | RRQ (Multipath, Flow-Binding) |
|---- (6) ----------------------------------------------->|
| | RRP | |
|<--- (7) ------------------------------------------------|
| MIP Tunnel through LTE Access |
|=====(8)==============================*==================|
| |
* *
(Policy-based Routing Rule) (Policy-based Routing Rule)
Figure 3: Multipath Negotiation - Example Call Flow
o (1): The mobile node (MN) attaches to the WLAN network and obtains
IP address configuration for its WLAN interface.
o (2)-(3): The mobile node sends a Registration Request (RRQ)
[RFC5944] to the home agent through the WLAN network. The message
includes the Multipath Section 4.1 and Flow-Binding Section 4.2
extensions. The home agent upon accepting the request sends a
Registration Reply (RRP) [RFC5944] with a value of (0 )in the Code
field of the Registration Reply.
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o (4): The mobile node and the home agent establish a bi-direction
IP tunnel over the WLAN network.
o (5): The mobile node attaches to LTE network and obtains IP
address configuration from that network.
o (6)-(7): The mobile node sends a Registration Request to the home
agent through the LTE network. The message includes the Multipath
and Flow-Binding extensions. The Flow-Binding extension indicates
that all HTTP flows need to be routed over WLAN network and if
WLAN access is not available, they need be routed over other
access networks. The negotiated policy also requires all Voice
related traffic flows to be routed over LTE network. The home
agent upon accepting the request sends a Registration Reply with a
value of (0) in the Code field of the Registration Reply.
o (8): The mobile node and the home agent establish a bi-direction
IP tunnel over the LTE network. The negotiated traffic flow
policy is applied. Both the home agent and the mobile node route
all the voice flows over the tunnel established through the LTE
access network and HTTP flows over WLAN network.
4. Message Extensions
This specification defines the following new extensions to Mobile IP.
4.1. Multipath Extension
This extension is used for requesting multipath support. It
indicates that the sender is requesting the home agent to register
the current care-of address listed in this Registration Request as
one of the many care-addresses through which the mobile node can be
reached. It is also for carrying the information specific to the
interface to which the care-of addresses that is being registered is
bound.
This extension is a non-skippable extension and MAY be added by the
mobile node to the Registration Request message. There MUST NOT be
more than one instance of this extension present in the message.
This extension MUST NOT be added by the home agent to the
Registration Reply.
This extension should be protected using the Mobile-Home
Authentication extension [RFC5944]. As specified in Section 3.2 and
Section 3.6.1.3 of [RFC5944], the mobile node MUST place this
Extension before the Mobile-Home Authentication Extension in the
registration messages, so that this extension is integrity protected.
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The format of this extension is as shown below. It adheres to the
long extension format described in [RFC5944].
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 | Sub-Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| If-ATT | If-Label | Binding-Id |B|O| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Multipath Extension
Type
Type: Multipath-Extension-Type (<IANA-1>)
Sub-Type
This field MUST be set to a value of 1 (Multipath Extension).
Length
The length of the extension in octets, excluding Type, Sub-Type
and Length fields. This field MUST be set to value of 4.
Interface Access-Technology Type (If-ATT)
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].
Interface Label (If-Label)
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
indexing forwarding policies. For example, the operator may
have a policy which binds an IP Flow "F1" to any interface with
label "Blue". When a registration through an interface
matching Label "Blue" gets activated, the home agent and the
mobile node establish an IP tunnel and the tunnel is marked
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with that label. Both the home agent and the mobile node
generate traffic rule for forwarding IP flow traffic "F1"
through mobile IP tunnel matching Label "Blue". The permitted
values for If-Label are 1 through 255.
Binding-Identifier (BID)
This 8-bit field is used for carrying the binding identifier.
It uniquely identifies a specific binding of the mobile node,
associated with this registration request. 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.
Bulk Re-registration Flag (B)
The (B) flag, if set to a value of (1), notifies the home agent
to update the binding lifetime of all the mobile node's
bindings, upon accepting this request. The (B) 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).
Registration Overwrite (O)
The (O) flag, if set to a value of (1), notifies the home agent
that upon accepting this request, it should replace all of the
mobile node's existing bindings with the new binding that will
be created upon accepting this request. The (O) 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 (R)
This 6-bit field is unused for now. The value MUST be
initialized to (0) by the sender and MUST be ignored by the
receiver.
4.2. Flow-Binding Extension
This extension contains information that can be used by the mobile
node and the home agent for binding mobile node's IP flows to a
specific multipath registration. There can be more than one instance
of this extension present in the message.
This extension is a non-skippable extension and MAY be added to the
Registration Request by the mobile node, or by the home agent to the
Registration Reply.
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This extension should be protected by Mobile-Home Authentication
extension [RFC5944]. As specified in Section 3.2 and Section 3.6.1.3
of [RFC5944], the mobile node MUST place this Extension before the
Mobile-Home Authentication Extension in the registration messages, so
that this extension is integrity protected.
The format of this extension is as shown below. It adheres to the
long extension format described in [RFC5944].
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 | Sub-Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action | BID Count | ... BID List ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TS Format | Traffic Selector ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Flow-Binding Extension
Type
Type: Multipath-Extension-Type (<IANA-1>)
Sub-Type
This field MUST be set to a value of 2 (Flow-Binding
Extension).
Length
The length of the extension in octets, excluding Type, Sub-Type
and Length fields.
Action
Action field identifies the traffic rule that needs to be
enforced. Following are the possible values.
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+---------+-------+-------------------------------------------------+
| Action | Value | Description |
+---------+-------+-------------------------------------------------+
| DROP | 0 | Drop matching packets. A filter rule |
| | | indicating a drop action MUST include a single |
| | | BID byte, the value of which MAY be set to 255 |
| | | by the sender and the value of which SHOULD be |
| | | ignored by the receiver. |
+---------+-------+-------------------------------------------------+
| FORWARD | 1 | Forward matching packets to the 1st BID in the |
| | | list of BIDs the filter rule is pointing to. |
| | | If the 1st BID becomes invalid (i.e., the |
| | | corresponding CoA is deregistered) use the next |
| | | BID in the list. |
+---------+-------+-------------------------------------------------+
Figure 6: Action Rules for the Traffic Selector
BID Count
Total number of binding identifiers that follow this field.
Permitted value for this field are 1 through 8; Each binding
identifier is represented as an unsigned integer in a single
octet field. There is no delimiter between two binding
identifier values, they are spaced consecutively.
TS Format
An 8-bit unsigned integer indicating the Traffic Selector
Format. Value (0) is reserved and MUST NOT be used. When the
value of TS Format field is set to (1), the format that follows
is the IPv4 Binary Traffic Selector specified in section 3.1 of
[RFC6088], and when the value of TS Format field is set to (2),
the format that follows is the IPv6 Binary Traffic Selector
specified in section 3.2 of [RFC6088]. The IPv6 traffic
selectors are only relevant when the mobile node registers IPv6
prefixes per [RFC5454].
Traffic Selector
A variable-length opaque field for including the traffic
specification identified by the TS format field. It identifies
the traffic selectors for matching the IP traffic and binding
them to specific binding identifiers.
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4.3. New Error Codes for Registration Reply
This document defines the following error code values for use by the
home agent in the Code field of the Registration Reply.
MULTIPATH_NOT_ALLOWED (Multipath Support not allowed for this mobile
node): <IANA-3>
INVALID_FB_IDENTIFIER (Invalid Flow Binding Identifier): <IANA-4>
5. Protocol Operation
5.1. Mobile Node Considerations
o The mobile node should register a care-of address for each of the
connected interfaces that it wishes to register with the home
agent. It can do so by sending a Registration Request to the home
agent through each of those interfaces.
o Each of the Registration Requests that is sent includes the
care-of address of the respective interface. The Registration
Request has to be routed through the specific interface for which
the registration is sough for. Some of these interfaces may be
connected to networks with a configured foreign agent on the link
and in such foreign agent based registrations, the care-of address
will be the IP address of the foreign agent.
o A Multipath extension (Section 4.1) reflecting the interface
parameters are present in each of the Registration Requests. This
serves as an indication to the home agent that the Registration
Request is a Multipath registration and the home agent will have
to register this care-of address as one of the many care-of
addresses through which the mobile node's home address is
reachable.
o If the mobile node is configured to exchange IP flow policy to the
home agent, then the Flow-Binding extension (Section 4.2)
reflecting the flow policy can be included in the message.
Otherwise, the Flow-Binding extension will not be included.
o The mobile node on receiving a Registration Reply with the code
value set to MULTIPATH_NOT_ALLOWED, MAY choose to register without
the Multipath extension specified in this document. This implies
the home agent has not enabled multipath support for this mobile
node and hence multipath support MUST be disabled on the mobile
node.
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o The mobile node on receiving a Registration Reply with the code
value set to INVALID_FB_IDENTIFIER, MUST re-register that specific
binding with the home agent.
o The mobile node at any time can extend the lifetime of a specific
care-of address registration by sending a Registration Request to
the home agent with a new lifetime value. The message MUST be
sent as the initial multipath registration and must be routed
through that specific interface. The message MUST include the
Multipath extension (Section 4.1) with the value in the Binding-Id
field set to the binding identifier assigned to that binding.
Alternatively, the home agent can send a single Registration
Request with the Bulk Re-registration Flag (B) set to a value of
(1). This serves as a request to the home agent to update the
registration lifetime of all the mobile node's registrations.
o The mobile node at any time can de-register a specific care-of
address by sending a Registration Request to the home agent with a
lifetime value of (0). The message must include the Multipath
extension (Section 4.1) with the value in the Binding-Id field set
to the binding identifier assigned to that binding Alternatively,
the home agent can send a single Registration Request with the
Bulk Re-registration Flag (B) set to a value of (1) and a lifetime
value of (0). This serves as a request to the home agent to
consider this request as a request to de-register all the mobile
node's care-of addresses.
o The mobile node at any time can update the parameters of a
specific registration by sending a Registration Request to the
home agent. This includes change of care-of address associated
with a previously registered interface. The message must be sent
as the initial multipath registration and must be routed through
that specific interface. The message must include the Multipath
extension (Section 4.1) with the value in the Binding-Id field set
to the binding identifier assigned to that binding and the
Overwrite Flag (O) flag MUST set to a value of (1).
o The mobile node on receiving a Registration Reply with the code
value set to 0 (registration accepted), will establish a mobile IP
tunnel to the home agent using that care-of address. When using
foreign agent care-of address, the tunnel is between the home
agent and the foreign agent. The tunnel encapsulation type and
any other parameters are based on the registration for that path.
If there is also an exchange of flow policy between the mobile
node and the home agent, with the use of Flow-Binding extensions
then the mobile node must set up the forwarding plane that matches
the flow policy.
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5.2. Home Agent Considerations
The home agent upon receiving a Registration Request from a mobile
node with a Multipath extension, should check if the mobile node is
authorized for multipath support. If multipath support is not
enabled, the home agent MUST reject the request with a registration
reply and with the code set to MULTIPATH_NOT_ALLOWED.
If the received Registration Request includes a Multipath extension
and additionally has the Bulk Re-registration (B) flag set to a value
of (1), then the home agent MUST extend the lifetime of all the
bindings associated with that mobile node.
The home agent upon receipt of a Registration Request with the Flow-
Binding Extension must process the extension and upon accepting the
flow policy must set up the forwarding plane that matches the flow
policy. If the home agent cannot identify any of the binding
identifiers then it MUST reject the request with a Registration Reply
and with the code set to INVALID_FB_IDENTIFIER.
If the received Registration Request includes a Multipath extension
and additionally has the Registration Overwrite (O) flag set to a
value of (1), then the home agent MUST consider this as a request to
replace all other mobile node's bindings with just one binding and
that is the binding associated with this request.
6. Routing Considerations
When multipath registration is enabled for a mobility node, there
will be multiple mobile IP tunnels established between a mobile node
and its home agent. These mobile IP tunnels appear to the forwarding
plane of the mobile node as equal-cost, point-to-point links.
If there is also an exchange of traffic flow policy between the
mobile node and the home agent, with the use of Flow-Binding
extensions (Section 4.2), then the mobile node's IP traffic can be
routed by the mobility entities as per the negotiated flow policy.
However, if multipath is enabled for a mobility session, without the
use of any flow policy exchange, then both the mobile node and the
home agent are required to have a pre-configured static flow policy.
The specific details on the semantics of this static flow policy is
outside the scope of this document.
In the absence of any established traffic flow policies, most IP
hosts support two alternative traffic load-balancing schemes, Per-
flow and Per-packet load balancing [RFC2991]. These load balancing
schemes allow the forwarding plane to evenly distribute traffic based
on the criteria of either a per-packet or on a per-flow basis, across
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all the available equal-cost links through which a destination can be
reached. The default forwarding behavior of per-flow load balancing
will ensure a given flow always takes the same path and will
eliminate any packet re-ordering issues and that is critical for
delay sensitive traffic. Whereas the per-destination load balancing
scheme leverages all the paths much more affectively, but with the
potential issue of packet re-ordering on the receiver end. This
issue will be specially magnified when the access links have very
different forwarding characteristics. A host can choose to enable
any of these approaches. Therefore, this specification recommends
the use of per-flow load balancing.
7. IANA Considerations
This document requires the following IANA actions.
o Action-1: This specification defines two new Mobile IP extensions,
Multipath extension and Flow-Binding extension. The format of the
Multipath extension is described in Section 4.1 and the format of
the Flow-Binding extension is described in Section 4.2. Both of
these extensions are non-skippable extensions to the Mobile IPv4
header in accordance to the long extension format of [RFC5944].
Both of these extensions use a common Type value, Multipath-
Extension-Type (<IANA-1>) but are identified using different Sub-
Type values. The type value <IANA-1> for these extension needs to
be allocated from the registry, "Extensions to Mobile IP
Registration Messages", at the URL,
<http://www.iana.org/assignments/mobileip-numbers>. The field,
"Permitted for Notification Messages" for this extension MUST be
set to "N"." RFC Editor: Please replace <IANA-1> in Section 4.1
and in Section 4.2 with the assigned value and update these
sections accordingly.
o Action-2: This specification defines a new message sub-type space,
Multipath Extension sub-type. This field is described in
Section 4.1. The values for this sub-type field needs to be
managed by IANA, under the Registry, Multipath Extension Sub-type
Registry. This specification reserves the following type values.
Approval of new Multipath Extension sub-type values are to be made
through IANA Expert Review [RFC5226].
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+=========================================================+
| 0 | Reserved |
+=========================================================+
| 1 | Multipath Extension |
+=========================================================+
| 2 | Flow-Binding Extension |
+=========================================================+
| | |
~ 3-254 | -- For future use -- ~
| | |
+=========================================================+
| 255 | Reserved |
+=========================================================+
o Action-3: This document defines new status code values,
MULTIPATH_NOT_ALLOWED (<IANA-3>) and INVALID_FB_IDENTIFIER
(<IANA-4>) for use by the home agent in the Code field of the
Registration Reply, as described in Section 4.3. These values
need to be assigned from the "Registration denied by the home
agent" registry at
<http://www.iana.org/assignments/mobility-parameters>. The
allocated value has to be greater than 127. RFC Editor: Please
replace <IANA-3> and <IANA-4> in Section 4.3 with the assigned
value and update this section accordingly.
8. Security Considerations
This specification allows a mobile node to establish multiple Mobile
IP tunnels with its home agent, by registering a care-of address for
each of its active roaming interfaces. This essentially allows the
mobile node's IP traffic to be routed through any of the tunnel paths
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 Mobile IP extensions, Multipath
extension and the Flow-Binding extension. These extensions are
specified to be included in Mobile IP control messages, which are
authenticated and integrity protected as described in [RFC5944].
Therefore, this specification does not weaken the security of Mobile
IP Protocol, and does not introduce any new security vulnerabilities.
9. Contributors
This document reflects discussions and contributions from the
following people:
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Ahmad Muhanna
asmuhanna@yahoo.com
Srinivasa Kanduru
skanduru@gmail.com
Vince Park
vpark@qualcomm.com
Hesham Soliman
hesham@elevatemobile.com
10. Acknowledgements
We like to thank Qin Wu, Shahriar Rahman, Mohana Jeyatharan, Yungui
Wang, Hui Deng Behcet Sarikaya, Jouni Korhonen, Michaela Vanderveen,
Antti Makela, Charles Perkins, Pierrick Siette, Vijay Gurbani, Barry
Leiba, Henrik Levkowetz, Pete McCann and Brian Haberman. for their
review and comments on this draft.
11. References
11.1. 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.
[RFC5944] Perkins, C., "IP Mobility Support for IPv4, Revised",
RFC 5944, November 2010.
[RFC6088] Tsirtsis, G., Giarreta, G., Soliman, H., and N. Montavont,
"Traffic Selectors for Flow Bindings", RFC 6088,
January 2011.
11.2. Informative References
[RFC2991] Thaler, D. and C. Hopps, "Multipath Issues in Unicast and
Multicast Next-Hop Selection", RFC 2991, November 2000.
[RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology",
RFC 3753, June 2004.
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[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
[RFC5454] Tsirtsis, G., Park, V., and H. Soliman, "Dual-Stack Mobile
IPv4", RFC 5454, March 2009.
[RFC6626] Tsirtsis, G., Park, V., Narayanan, V., and K. Leung,
"Dynamic Prefix Allocation for Network Mobility for Mobile
IPv4 (NEMOv4)", RFC 6626, May 2012.
Authors' Addresses
Sri Gundavelli (editor)
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
EMail: sgundave@cisco.com
Kent Leung
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
EMail: kleung@cisco.com
George Tsirtsis
Qualcomm
EMail: tsirtsis@qualcomm.com
Alexandru Petrescu
CEA LIST
Communicating Systems Laboratory, Point Courrier 94
Gif-sur-Yvette F-91191
France
Phone: +33 169089223
EMail: alexandru.petrescu@cea.fr
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