Netext WG S. Krishnan
Internet-Draft Ericsson
Intended status: Standards Track R. Koodli
Expires: November 8, 2012 Cisco Systems
P. Loureiro
NEC
Q. Wu
Huawei
A. Dutta
NIKSUN
May 7, 2012
Localized Routing for Proxy Mobile IPv6
draft-ietf-netext-pmip-lr-09
Abstract
Proxy Mobile IPv6 (PMIPv6) is a network based mobility management
protocol that enables IP mobility for a host without requiring its
participation in any mobility-related signaling. PMIPv6 requires all
communications to go through the local mobility anchor. As this can
be suboptimal, localized routing (LR) allows mobile nodes attached to
the same or different mobile access gateways to route traffic by
using localized forwarding or a direct tunnel between the gateways.
This document proposes initiation, utilization and termination
mechanisms for localized routing between mobile access gateways
within a proxy mobile IPv6 domain. It defines two new signaling
messages, Localized Routing Initiation (LRI) and Local Routing
Acknowledgment (LRA), that are used to realize this mechanism.
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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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 November 8, 2012.
Krishnan, et al. Expires November 8, 2012 [Page 1]
Internet-Draft PMIPv6 Localized Routing May 2012
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Initiation of Localized Routing . . . . . . . . . . . . . . . 5
2.1. MAG behavior . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. LMA behavior . . . . . . . . . . . . . . . . . . . . . . . 5
3. Teardown of Localized Routing . . . . . . . . . . . . . . . . 6
4. Conventions used in this document . . . . . . . . . . . . . . 7
5. Scenario A11: Two MNs attached to the same MAG and LMA . . . . 8
5.1. Handover Considerations . . . . . . . . . . . . . . . . . 10
6. Scenario A21: Two MNs attached to different MAGs but same
LMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.1. Handover Considerations . . . . . . . . . . . . . . . . . 13
6.2. Tunneling between the MAGs . . . . . . . . . . . . . . . . 13
7. Scenario A12: Two MNs attached to the same MAG with
different LMAs . . . . . . . . . . . . . . . . . . . . . . . . 15
7.1. Handover Considerations . . . . . . . . . . . . . . . . . 16
8. Scenario A22: Two MNs attached to different MAGs with
different LMAs . . . . . . . . . . . . . . . . . . . . . . . . 17
9. IPv4 support in Localized Routing . . . . . . . . . . . . . . 18
10. Message Formats . . . . . . . . . . . . . . . . . . . . . . . 19
10.1. Localized Routing Initiation (LRI) . . . . . . . . . . . . 19
10.2. Localized Routing Acknowledgment (LRA) . . . . . . . . . . 20
11. New Mobility Option . . . . . . . . . . . . . . . . . . . . . 22
11.1. MAG IPv6 Address . . . . . . . . . . . . . . . . . . . . . 22
12. Configuration Variables . . . . . . . . . . . . . . . . . . . 23
13. Security Considerations . . . . . . . . . . . . . . . . . . . 24
14. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
15. Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
16. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 27
17. References . . . . . . . . . . . . . . . . . . . . . . . . . . 28
17.1. Normative References . . . . . . . . . . . . . . . . . . . 28
Krishnan, et al. Expires November 8, 2012 [Page 2]
Internet-Draft PMIPv6 Localized Routing May 2012
17.2. Informative References . . . . . . . . . . . . . . . . . . 28
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 29
Krishnan, et al. Expires November 8, 2012 [Page 3]
Internet-Draft PMIPv6 Localized Routing May 2012
1. Introduction
Proxy Mobile IPv6 [RFC5213] describes the protocol operations to
maintain reachability and session persistence for a Mobile Node (MN)
without the explicit participation from the MN in signaling
operations at the Internet Protocol (IP) layer. In order to
facilitate such network-based mobility, the PMIPv6 protocol defines a
Mobile Access Gateway (MAG), which acts as a proxy for the Mobile
IPv6 [RFC6275] signaling, and the Local Mobility Anchor (LMA) which
acts similar to a Home Agent. The LMA and the MAG establish a
bidirectional tunnel for forwarding all data traffic belonging to the
Mobile Nodes. In the case where both endpoints are located in the
same PMIPv6 domain, this can be suboptimal and results in higher
delay and congestion in the network. Moreover, it increases
transport costs and traffic load at the LMA.
To overcome these issues, localized routing can be used to allow
nodes attached to the same or different MAGs to directly exchange
traffic by using localized forwarding or a direct tunnel between the
gateways. [RFC6279] defines the problem statement for PMIPv6
localized routing. This document describes a solution for PMIPv6
localized routing between two MNs in the same PMIPv6 domain. The
protocol specified here assumes that each MN is attached to a MAG and
that each MN's MAG has established a binding for the attached MN at
its selected LMA according to [RFC5213]. The protocol builds on the
scenarios defined in [RFC6279].
Krishnan, et al. Expires November 8, 2012 [Page 4]
Internet-Draft PMIPv6 Localized Routing May 2012
2. Initiation of Localized Routing
Since the traffic to be localized passes through both the LMA and the
MAGs, it is possible, at least in some scenarios, for either of them
to initiate Localized Routing (LR). In order to eliminate ambiguity,
the protocol described in this document selects the initiator of the
LR based on the following rules.
2.1. MAG behavior
The MAG MUST initiate LR if both the communicating MNs are attached
to it and the MNs are anchored at different LMAs. The MAG MUST NOT
initiate LR in any other case.
2.2. LMA behavior
The LMA MUST initiate LR if both the communicating MNs are anchored
to it. The LMA MUST NOT initiate LR in any other case.
Krishnan, et al. Expires November 8, 2012 [Page 5]
Internet-Draft PMIPv6 Localized Routing May 2012
3. Teardown of Localized Routing
The use of localized routing is not persistent. Localized routing
has a defined lifetime as specified by the initiator, upon the expiry
of which, the forwarding MUST revert to using bidirectional
tunneling. When localized routing ceases, the corresponding LRE
entries MUST be removed.
If the initiator of LR wishes to terminate localized routing before
the expiry of the lifetime specified in the LRI message, it MUST do
so by sending a new LRI message with the lifetime set to zero.
Krishnan, et al. Expires November 8, 2012 [Page 6]
Internet-Draft PMIPv6 Localized Routing May 2012
4. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
This document also uses the terminology defined in Section 2 of
[RFC6279].
Krishnan, et al. Expires November 8, 2012 [Page 7]
Internet-Draft PMIPv6 Localized Routing May 2012
5. Scenario A11: Two MNs attached to the same MAG and LMA
In this scenario, the two Mobile Nodes involved in communication are
attached to a single MAG and both are anchored at the same LMA as
shown in Figure 1.
Internet
:
|
|
+-----+
| LMA |
+-----+
|
|
|
+-----+
| MAG |
+-----+
: :
+---+ +---+
|MN1| |MN2|
+---+ +---+
Figure 1
The LMA initiates a localized routing session by detecting traffic
between two MNs attached to the same MAG. The exact traffic
identification mechanism is not specified in this document, and is
left open for implementations and specific deployments. An example
trigger could be that an application-layer signaling entity detects
the possibility of localized routing and notifies the LMA about the
two end-points, and the LMA determines that the two end-points are
attached to the same MAG. Such a trigger mechanism offers localized
routing at the granularity of an individual application session,
providing flexibility in usage. It is also possible that one of the
mobility entities (LMA or MAG) could decide to initiate localized
routing based on configured policy. Please note that a MAG
implementing the protocol specified in this specification will not
dynamically initiate LR in the same LMA case (i.e. by sending an
LRI), but can statically initiate LR based on the
EnableMAGLocalRouting configuration variable specified in [RFC5213].
Krishnan, et al. Expires November 8, 2012 [Page 8]
Internet-Draft PMIPv6 Localized Routing May 2012
+----+ +----+ +----+ +----+
|MN1 | |MN2 | |MAG1| |LMA |
+----+ +----+ +----+ +----+
| | | |
| data | data |
|<--------------------->|<------------->|
| | | |
| | data | data |
| |<--------->|<------------->|
| | | LR decision
| | | LRI(Opt1) |
| | |<--------------|
| | | |
| | | LRA(Opt2) |
| | |-------------->|
| | | |
| data | |
|<--------------------->| |
| | | |
| | data | |
| |<--------->| |
| | | |
| | | |
Opt1: MN1-ID,MN1-HNP,MN2-ID,MN2-HNP
Opt2: U=0,MN1-ID,MN1-HNP,MN2-ID,MN2-HNP
where U is the flag defined in Section 9.1 and 9.2.
Figure 2
After detecting a possibility for localized routing, the LMA SHOULD
construct a Localized Routing Initiation (LRI) message that is used
to signal the intent to initiate localized routing and to convey
parameters for the same. This is a Mobility Header message and it
MUST contain the MN-Identifier and the Home Network Prefix (as
Mobility Header options) for each of the MNs involved. The LMA MUST
then send the LRI message to the MAG (MAG1) where the two MNs are
attached as shown in Figure 2.
The MAG (MAG1) MUST verify the attachment status of the two MNs
locally by checking the binding cache. The MAG MUST then verify if
the EnableMAGLocalRouting flag is set to 1. If it is not, the MAG
has not been configured to allow localized routing and it MUST reject
the LRI and MUST send an LRA with status code "Localized Routing Not
Allowed". Please note that this does not update behavior specified
in [RFC5213] but merely implements the LMA enforcement specified in
Section 6.10.3. of [RFC5213]. If MAG is configured to allow
Krishnan, et al. Expires November 8, 2012 [Page 9]
Internet-Draft PMIPv6 Localized Routing May 2012
localized routing it MUST then create Localized Routing Entries
(LREs) for each direction of the communication between the two MNs.
The exact form of the forwarding entries is left for the
implementations to decide; however, they SHOULD contain the Home
Network Prefix (HNP) corresponding to the destination IP address and
a next-hop identifier (e.g. the layer 2 address of the next hop).
These LREs MUST override the Binding Update List(BUL) entries for the
specific HNPs identified in the LRI message. Hence all traffic
matching the HNPs is forwarded locally.
If the MAG is unable to deliver packets using the LREs, it is
possible that one of the MNs is no longer attached to the MAG.
Hence, the MAG MUST fall back to using the BUL entry, and the LMA
MUST forward the received packets using its Binding Cache Entry
(BCE).
After processing the LRI message the MAG MUST respond with a Local
Routing Acknowledgment (LRA) message. This Mobility Header message
MUST also include the MN-ID and the HNP for each of the communicating
MNs as well as an appropriate Status code indicating the outcome of
LRI processing. Status code 0 indicates localized routing was
successfully offered by the MAG. Any other value for Status code
indicates the reason for the failure to offer localized routing
service. When Status code is 0, the LMA sets a flag in the BCE
corresponding to the HNPs to record that localized routing is in
progress for that HNP.
5.1. Handover Considerations
If one of the MNs, say MN1, detaches from the MAG and attaches to
another MAG (say nMAG) the localized routing state needs to be re-
established. When the LMA receives the PBU from nMAG for MN1, it
will see that localized routing is active for MN1. It MUST hence
initiate LR at nMAG and update the LR state of MAG. After the
handover completes, the localized routing will resemble Scenario A21.
The pMAG MUST follow the forwarding rules described in Section 6.10.5
of [RFC5213] and decide that it will no longer perform LR for MN1.
Krishnan, et al. Expires November 8, 2012 [Page 10]
Internet-Draft PMIPv6 Localized Routing May 2012
6. Scenario A21: Two MNs attached to different MAGs but same LMA
The LMA may choose to support local forwarding to mobile nodes
attached to two different MAGs within a single PMIPv6 domain.
Internet
:
|
|
+-----+
| LMA |
+-----+
|
|
+----+-----+
| |
+----+ +----+
|MAG1| |MAG2|
+----+ +----+
: :
+---+ +---+
|MN1| |MN2|
+---+ +---+
Figure 3
As earlier, the LMA initiates LR as a response to some trigger
mechanism. In this case, however, it MUST send two separate LRI
messages to the two MAGs. In addition to the MN-ID and the HNP
options, each LRI message MUST contain the IP Address of the
counterpart MAG. When the MAG IP Address option is present, each MAG
MUST create a local forwarding entry such that the packets for the MN
attached to the remote MAG are sent over a tunnel associated with
that remote MAG. The tunnel between the MAGs is assumed to be
established following the considerations mentioned in Section 6.2.
Krishnan, et al. Expires November 8, 2012 [Page 11]
Internet-Draft PMIPv6 Localized Routing May 2012
+----+ +----+ +----+ +----+ +----+
|MN1 | |MN2 | |MAG1| |MAG2| |LMA |
+----+ +----+ +----+ +----+ +----+
| | | | |
| data | data |
|<--------------------->|<----------------------->|
| | | | |
| | data | data |
| |<--------------------->|<----------->|
| | | | |
| | | | |
| | | LRI(Opt1) |
| | |<------------------------|
| | | | |
| | | | LRI(Opt2) |
| | | |<------------|
| | | | |
| | | LRA(Opt3) |
| | |------------------------>|
| | | | |
| | | | LRA(Opt4) |
| | | |------------>|
| | | | |
| | | | |
| | | | |
| data | data | |
|<--------------------->|<--------->| |
| | | | |
| | data | |
| |<--------------------->| |
| | | | |
| | | | |
Opt1: MN1-ID,MN1-HNP,MAG2-IPv6-Address
Opt2: MN2-ID,MN2-HNP,MAG1-IPv6-Address
Opt3: U=0,MN1-ID,MN1-HNP,MAG2-IPv6-Address
Opt4: U=0,MN2-ID,MN2-HNP,MAG1-IPv6-Address
where U is the flag defined in Section 9.1 and 9.2.
Figure 4
In this case, each MAG responds to the LRI with an LRA message. All
subsequent packets are routed between the MAGs locally, without
traversing the LMA. If one of the MAGs (say MAG1) responds with a
successful LRA (Status value is zero) and the other (say
MAG2)responds with an error (Status value is non-zero) LR will still
be performed in one direction (MN1->MAG1->MAG2->MN2), but the packets
Krishnan, et al. Expires November 8, 2012 [Page 12]
Internet-Draft PMIPv6 Localized Routing May 2012
flowing the other way will take the LMA path
(MN2->MAG2->LMA->MAG1->MN1).
The protocol does not require any synchronization between the MAGs
before local forwarding begins. Each MAG begins its local forwarding
independent of the other.
No synchronization between MAGs is required because each MAG
initiates LR in one direction. After the LMA instructs MAG1 to
initiate LR, packets from MN1 to MN2 will take the path
MN1->MAG1->MAG2->MN2 while those from MN2 to MN1 will take the path
MN2->MAG2->LMA->MAG1->MN1 until LMA instructs MAG2 to do so as well.
At any instant a MAG will forward a packet either towards another MAG
or its own LMA and hence there would be no duplication of packets.
6.1. Handover Considerations
If one of the MNs, say MN1, detaches from its current MAG (in this
case MAG1) and attaches to another MAG (say nMAG1) the localized
routing state needs to be re-established. When the LMA receives the
PBU from nMAG1 for MN1, it will see that localized routing is active
for MN1. The LMA MUST then initiate LR at nMAG1 and update the LR
state of MAG2 to use nMAG1 instead of MAG1.
6.2. Tunneling between the MAGs
In order to support localized routing both MAGs SHOULD support the
following encapsulation modes for the user packets, which are also
defined for the tunnel between the LMA and MAG:
o IPv4-or-IPv6-over-IPv6 [RFC5844]
o IPv4-or-IPv6-over-IPv4 [RFC5844]
o IPv4-or-IPv6-over-IPv4-UDP [RFC5844]
o TLV-header UDP tunneling [RFC5845]
o Generic Routing Encapsulation (GRE) tunneling with or without GRE
key(s) [RFC5845]
MAG1 and the MAG2 MUST use the same tunneling mechanism for the data
traffic tunneled between them. The encapsulation mode to be employed
SHOULD be configurable. It is RECOMMENDED that:
1. As the default behavior, the inter-MAG tunnel uses the same
encapsulation mechanism as that being used for the PMIPv6 tunnel
between the LMA and the MAGs. MAG1 and MAG2 automatically start
Krishnan, et al. Expires November 8, 2012 [Page 13]
Internet-Draft PMIPv6 Localized Routing May 2012
using the same encapsulation mechanism without a need for a
special configuration on the MAGs or a dynamic tunneling
mechanism negotiation between them.
2. Configuration on the MAGs can override the default mechanism
specified in Option 1 above. MAG1 and MAG2 MUST be configured
with the same mechanism, and this configuration is most likely to
be uniform throughout the PMIPv6 domain. If the packets on the
PMIPv6 tunnel cannot be uniquely mapped on to the configured
inter-MAG tunnel, this scenario is not applicable, and Option 3
below SHOULD directly be applied.
3. An implicit or explicit tunnel negotiation mechanism between the
MAGs can override the default mechanism specified in Option 1
above. The employed tunnel negotiation mechanism is outside the
scope of this document.
Krishnan, et al. Expires November 8, 2012 [Page 14]
Internet-Draft PMIPv6 Localized Routing May 2012
7. Scenario A12: Two MNs attached to the same MAG with different LMAs
In this scenario, both the MNs are attached to the same MAG, but are
anchored at two different LMAs. MN1 is anchored at LMA1 and MN2 is
anchored at LMA2. Note that the two LMAs are part of the same
Provider Domain.
Internet
: :
+------------------+
| |
+----+ +----+
|LMA1| |LMA2|
+----+ +----+
| |
| |
+------------------+
|
|
|
+-----+
| MAG |
+-----+
: :
+---+ +---+
|MN1| |MN2|
+---+ +---+
Figure 5
Hence, neither LMA has a means to determine that the two Mobile Nodes
are attached to the same MAG. Only the MAG can possibly determine
that the two Mobile Nodes involved in communication are attached to
it. Therefore, the localized routing MUST be initiated by the MAG.
The MAG sends an LRI message containing the MN-ID, HNP and the
counterpart LMA address to each LMA. Each LMA makes decision to
support local forwarding independently, based on, among others,
policy configuration for the counterpart LMA. Each LMA MUST respond
to the LRI message with an LRA message. If the initiation of LR on
the LMA was successful, the Status value in the received LRA would be
set to zero. After the MAG receives both the LRA messages each with
Status value set to zero (success) from the two different LMAs, the
MAG will conclude that it can provide local forwarding support for
the two Mobile Nodes.
Krishnan, et al. Expires November 8, 2012 [Page 15]
Internet-Draft PMIPv6 Localized Routing May 2012
+----+ +----+ +----+ +----+ +----+
|MN1 | |MN2 | |MAG | |LMA1| |LMA2|
+----+ +----+ +----+ +----+ +----+
| | | | |
| data | data | data |
|<--------------------->|<--------->|<----------->|
| | | | |
| | data | data |
| |<--------->|<----------------------->|
| | | | |
| | | | |
| | | LRI(Opt1) | |
| | |---------->| |
| | | | |
| | | LRI(Opt2) |
| | |------------------------>|
| | | | |
| | | LRA(Opt3) | |
| | |<----------| |
| | | | |
| | | LRA(Opt4) |
| | |<------------------------|
| | | | |
| | | | |
| | | | |
| data | | |
|<--------------------->| | |
| | | | |
| | data | | |
| |<--------->| | |
| | | | |
| | | | |
Opt1: MN1-ID,MN1-HNP
Opt2: MN2-ID,MN2-HNP
Opt3: U=0,MN1-ID,MN1-HNP
Opt4: U=0,MN2-ID,MN2-HNP
where U is the flag defined in Section 9.1 and 9.2.
Figure 6
7.1. Handover Considerations
If one of the MNs, say MN1, detaches from its current MAG (in this
case MAG1) and attaches to another MAG (say nMAG1), the current MAG
MUST immediately stop using the LRE and MUST send all packets
originated by the other MN (MN2) towards its LMA (in this case LMA2).
Krishnan, et al. Expires November 8, 2012 [Page 16]
Internet-Draft PMIPv6 Localized Routing May 2012
8. Scenario A22: Two MNs attached to different MAGs with different LMAs
This scenario will not be covered in this document since PMIPv6 does
not define any form of inter-LMA communications. When a supported
scenario, such as Scenario A12, morphs into Scenario A22 the node
that initiated the localized routing session MUST tear it down in
order to prevent lasting packet loss. This can result in transient
packet loss when routing switches between the localized path into the
normal path through the LMAs. In applications that are loss
sensitive, this can lead to observable service disruptions. In
deployments where Scenario A22 is possible, the use of localized
routing is NOT RECOMMENDED when packet-loss-sensitive applications
are in use.
Krishnan, et al. Expires November 8, 2012 [Page 17]
Internet-Draft PMIPv6 Localized Routing May 2012
9. IPv4 support in Localized Routing
PMIPv6 MNs can use an IPv4 HoA as described in [RFC5844]. In order
to support the setup and maintenance of localized routes for these
IPv4 HoAs in PMIPv6, MAGs MUST add the IPv4 HoAs into their LREs.
The MAGs MUST also support encapsulation of IPv4 packets as described
in [RFC5844]. The localized routing protocol messages MUST include a
IPv4 HoA option in their signaling messages in order to support IPv4
addresses for localized routing.
If the transport network between the PMIPv6 entities involved in
localized routing is IPv4-only, the LRI and LRA messages MUST be
encapsulated similar to the PBU/PBA messages as specified in
[RFC5844]. The encapsulation mode used SHOULD be identical to the
one used to transport PBU and PBA messages.
Krishnan, et al. Expires November 8, 2012 [Page 18]
Internet-Draft PMIPv6 Localized Routing May 2012
10. Message Formats
The Localized routing messages use two new mobility header type (TBA1
and TBA2). The LRI message requests creation or deletion of
localized routing state and the LRA message acknowledges the creation
or deletion of such localized routing state.
10.1. Localized Routing Initiation (LRI)
The LRI messages uses a new mobility header type (TBA1). The LMA
sends an LRI message to a MAG to request local forwarding for a pair
of MNs. The MAG may also send this message to request the two LMAs
for offering local forwarding as described in Section 7 .
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sequence Number: A monotonically increasing integer. Set by a
sending node in a request message, and used to match a reply to
the request.
Reserved: This field is unused. MUST be set zero.
Lifetime: The requested time in seconds for which the sender
wishes to have local forwarding. A value of 0xffff (all ones)
indicates an infinite lifetime. When set to 0, indicates a
request to stop localized routing.
Mobility Options: MUST contain two separate MN-ID options,
followed by one or more HNPs for each of the MNs. For instance,
for Mobile Nodes MN1 and MN2 with identifiers MN1-ID, MN2-ID and
Home Network Prefixes MN1-HNP and MN2-HNP, the following tuple
in the following order MUST be present: [MN1-ID, MN1-HNP],
[MN2-ID, MN2-HNP]. The MN-ID and HNP options are the same as in
[RFC5213]. MAY contain the remote MAG IPv6 address option,
which is formatted identically to the HNP option, except that it
uses a different Type code and the Prefix Length is always equal
Krishnan, et al. Expires November 8, 2012 [Page 19]
Internet-Draft PMIPv6 Localized Routing May 2012
to 128 bits (see Section 10.1).
The LRI message SHOULD be re-transmitted if a corresponding LRA
message is not received within LRA_WAIT_TIME time units, up to a
maximum of LRI_RETRIES, each separated by LRA_WAIT_TIME time units.
10.2. Localized Routing Acknowledgment (LRA)
The LRA messages uses a new mobility header type (TBA2). A MAG sends
an LRA message to the LMA as a response to the LRI message. An LMA
may also send this message to a MAG as a response to the LRI message
as described in Section 7 .
Krishnan, et al. Expires November 8, 2012 [Page 20]
Internet-Draft PMIPv6 Localized Routing May 2012
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U| Reserved | Status | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sequence Number: is copied from the sequence number field of the
LRI message being responded to.
'U' flag: When set to 1, the LRA message is sent unsolicited.
The Lifetime field indicates a new requested value. The MAG MUST
wait for the regular LRI message to confirm that the request is
acceptable to the LMA.
Reserved: This field is unused. MUST be set zero.
Status:
0: Success
128: Localized Routing Not Allowed
129: MN not attached
Lifetime: The time in seconds for which the local forwarding is
supported. Typically copied from the corresponding field in the
LRI message.
Mobility Options: When Status code is 0, MUST contain the
[MN-ID, HNP] tuples in the same order as in the LRI message.
When Status code is not 0, MUST contain only those [MN-ID, HNP]
tuples for which local forwarding is supported. The MN-ID and
HNP options are the same as in [RFC5213].
Krishnan, et al. Expires November 8, 2012 [Page 21]
Internet-Draft PMIPv6 Localized Routing May 2012
11. New Mobility Option
11.1. MAG IPv6 Address
The MAG IPv6 address mobility option contains the IPv6 address of a
MAG involved in the localized routing. The MAG IPv6 address option
has an alignment requirement of 8n+4.
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 | Reserved | Address Length|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ MAG IPv6 Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
TBA3
Length
8-bit unsigned integer indicating the length of the option
in octets, excluding the type and length fields. This field
MUST be set to 18.
Reserved (R)
This 8-bit field is unused for now. The value MUST be
initialized to 0 by the sender and MUST be ignored by the
receiver.
Address Length
This field MUST be set to 128.
MAG IPv6 Address
A 16 byte field containing the MAG's IPv6 Address.
Krishnan, et al. Expires November 8, 2012 [Page 22]
Internet-Draft PMIPv6 Localized Routing May 2012
12. Configuration Variables
The LMA and the MAG must allow the following variables to be
configurable.
LRA_WAIT_TIME: This variable is used to set the time interval in
seconds between successive retransmissions of an LRI message. The
default value is 3 seconds.
LRI_RETRIES: This variable indicates the maximum number of times the
initiator retransmits an LRI message before stopping. The default
value for this variable is 3.
Krishnan, et al. Expires November 8, 2012 [Page 23]
Internet-Draft PMIPv6 Localized Routing May 2012
13. Security Considerations
The protocol inherits the the threats to [RFC5213] that are
identified in [RFC4832]. The protocol specified in this document
uses the same security association as defined in [RFC5213] for use
between the LMA and the MAG to protect the LRI and LRA messages.
This document also assumes the pre-existence of a MAG-MAG security
association if LR needs to be supported between them. Support for
integrity protection using IPsec is REQUIRED, but support for
confidentiality is OPTIONAL. The MAGs MUST perform ingress filtering
on the MN sourced packets before encapsulating them into MAG-MAG
tunnels in order to prevent address spoofing.
Krishnan, et al. Expires November 8, 2012 [Page 24]
Internet-Draft PMIPv6 Localized Routing May 2012
14. IANA Considerations
The Localized Routing Initiation, described in Section 10.1 and the
Localized Routing Acknowledgment, described in Section 10.2 each
require a Mobility Header Type (TBA1 and TBA2) from the Mobility
Header Types registry at
http://www.iana.org/assignments/mobility-parameters
The MAG IPv6 Address requires a Mobility Option Type (TBA3) from the
Mobility Options registry at
http://www.iana.org/assignments/mobility-parameters
Krishnan, et al. Expires November 8, 2012 [Page 25]
Internet-Draft PMIPv6 Localized Routing May 2012
15. Authors
This draft merges ideas from five different drafts addressing the
PMIP localized routing problem. The authors of these drafts are
listed below (in alphabetical order)
Kuntal Chowdhury <kchowdhury@starentnetworks.com>
Ashutosh Dutta <adutta@niksun.com>
Rajeev Koodli <rkoodli@starentnetworks.com>
Suresh Krishnan <suresh.krishnan@ericsson.com>
Marco Liebsch <marco.liebsch@nw.neclab.eu>
Paulo Loureiro <paulo.loureiro@nw.neclab.eu>
Desire Oulai <desire.oulai@videotron.com>
Behcet Sarikaya <sarikaya@ieee.org>
Qin Wu <sunseawq@huawei.com>
Hidetoshi Yokota <yokota@kddilabs.jp>
Krishnan, et al. Expires November 8, 2012 [Page 26]
Internet-Draft PMIPv6 Localized Routing May 2012
16. Acknowledgments
The authors would like to thank Sri Gundavelli, Julien Abeille, Tom
Taylor, Kent Leung, Mohana Jeyatharan, Jouni Korhonen, Glen Zorn,
Ahmad Muhanna, Zoltan Turanyi, Dirk von Hugo, Pete McCann, Xiansong
Cui, Carlos Bernardos, Basavaraj Patil, Jari Arkko, Mary Barnes, Les
Ginsberg, Russ Housley, Carl Wallace, Ralph Droms and Adrian Farrel
for their comments and suggestions.
Krishnan, et al. Expires November 8, 2012 [Page 27]
Internet-Draft PMIPv6 Localized Routing May 2012
17. References
17.1. 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.
[RFC5845] Muhanna, A., Khalil, M., Gundavelli, S., and K. Leung,
"Generic Routing Encapsulation (GRE) Key Option for Proxy
Mobile IPv6", RFC 5845, June 2010.
[RFC6275] Perkins, C., Johnson, D., and J. Arkko, "Mobility Support
in IPv6", RFC 6275, July 2011.
17.2. Informative References
[RFC4832] Vogt, C. and J. Kempf, "Security Threats to Network-Based
Localized Mobility Management (NETLMM)", RFC 4832,
April 2007.
[RFC6279] Liebsch, M., Jeong, S., and Q. Wu, "Proxy Mobile IPv6
(PMIPv6) Localized Routing Problem Statement", RFC 6279,
June 2011.
Krishnan, et al. Expires November 8, 2012 [Page 28]
Internet-Draft PMIPv6 Localized Routing May 2012
Authors' Addresses
Suresh Krishnan
Ericsson
8400 Blvd Decarie
Town of Mount Royal, Quebec
Canada
Phone: +1 514 345 7900 x42871
Email: suresh.krishnan@ericsson.com
Rajeev Koodli
Cisco Systems
Email: rkoodli@cisco.com
Paulo Loureiro
NEC
Email: paulo.loureiro@nw.neclab.eu
Qin Wu
Huawei
Email: Sunseawq@huawei.com
Ashutosh Dutta
NIKSUN
Email: adutta@niksun.com
Krishnan, et al. Expires November 8, 2012 [Page 29]