Internet DRAFT - draft-zuniga-dmm-gap-analysis
draft-zuniga-dmm-gap-analysis
DMM WG JC. Zuniga
Internet-Draft InterDigital
Intended status: Informational CJ. Bernardos
Expires: June 22, 2013 UC3M
T. Melia
Alcatel-Lucent
C. Perkins
Futurewei
December 19, 2012
Mobility Practices and DMM Gap Analysis
draft-zuniga-dmm-gap-analysis-03
Abstract
This document describes practices for the deployment of existing
mobility protocols in a distributed mobility management (DMM)
environment, and identifies the limitations in the current practices
with respect to providing the expected DMM functionality.
The practices description and gap analysis are performed for IP-based
mobility protocols, dividing them into three main families: IP
client-based, IP network-based, and 3GPP mobility solutions.
Status of this Memo
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This Internet-Draft will expire on June 22, 2013.
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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Practices: deployment of existing solutions in a DMM
fashion . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Client-based IP mobility . . . . . . . . . . . . . . . . . 4
2.1.1. Mobile IPv6 / NEMO . . . . . . . . . . . . . . . . . . 5
2.1.2. Mobile IPv6 Route Optimization . . . . . . . . . . . . 6
2.1.3. Hierarchical Mobile IPv6 . . . . . . . . . . . . . . . 7
2.1.4. Home Agent switch . . . . . . . . . . . . . . . . . . 8
2.1.5. IP Flow Mobility . . . . . . . . . . . . . . . . . . . 8
2.1.6. Source Address Selection . . . . . . . . . . . . . . . 8
2.2. Network-based IP mobility . . . . . . . . . . . . . . . . 9
2.2.1. Proxy Mobile IPv6 . . . . . . . . . . . . . . . . . . 9
2.2.2. Local Routing . . . . . . . . . . . . . . . . . . . . 10
2.2.3. LMA runtime assignment . . . . . . . . . . . . . . . . 10
2.2.4. Source Address Selection . . . . . . . . . . . . . . . 11
2.2.5. Multihoming in PMIPv6 . . . . . . . . . . . . . . . . 11
2.3. 3GPP mobility . . . . . . . . . . . . . . . . . . . . . . 11
2.3.1. GPRS Tunnelling Protocol (GTP) and DSMIPv6 . . . . . . 12
2.3.2. Local IP Access and Selected IP Traffic Offload
(LIPA-SIPTO) . . . . . . . . . . . . . . . . . . . . . 13
2.3.3. LIPA Mobility and SIPTO at the Local Network
(LIMONET) . . . . . . . . . . . . . . . . . . . . . . 13
2.3.4. Data IDentification in ANDSF (DIDA) and Operator
Policies for IP Interface Selection (OPIIS) . . . . . 13
2.3.5. Multi-Access PDN Connectivity (MAPCON) . . . . . . . . 14
3. Gap Analysis: limitations in current practices . . . . . . . . 14
3.1. Client-based IP mobility . . . . . . . . . . . . . . . . . 14
3.1.1. REQ1: Distributed deployment . . . . . . . . . . . . . 14
3.1.2. REQ2: Transparency to Upper Layers when needed . . . . 15
3.1.3. REQ3: IPv6 deployment . . . . . . . . . . . . . . . . 16
3.1.4. REQ4: Existing mobility protocols . . . . . . . . . . 16
3.1.5. REQ5: Compatibility . . . . . . . . . . . . . . . . . 17
3.1.6. REQ6: Security considerations . . . . . . . . . . . . 17
3.2. Network-based IP mobility . . . . . . . . . . . . . . . . 18
3.2.1. REQ1: Distributed deployment . . . . . . . . . . . . . 18
3.2.2. REQ2: Transparency to Upper Layers when needed . . . . 19
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3.2.3. REQ3: IPv6 deployment . . . . . . . . . . . . . . . . 20
3.2.4. REQ4: Existing mobility protocols . . . . . . . . . . 20
3.2.5. REQ5: Compatibility . . . . . . . . . . . . . . . . . 20
3.2.6. REQ6: Security considerations . . . . . . . . . . . . 21
3.3. 3GPP mobility . . . . . . . . . . . . . . . . . . . . . . 21
3.3.1. REQ1: Distributed deployment . . . . . . . . . . . . . 21
3.3.2. REQ2: Transparency to Upper Layers when needed . . . . 21
3.3.3. REQ3: IPv6 deployment . . . . . . . . . . . . . . . . 21
3.3.4. REQ4: Existing mobility protocols . . . . . . . . . . 21
3.3.5. REQ5: Compatibility . . . . . . . . . . . . . . . . . 22
3.3.6. REQ6: Security considerations . . . . . . . . . . . . 22
4. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.1. Independent solution analysis . . . . . . . . . . . . . . 22
4.2. Functional analysis . . . . . . . . . . . . . . . . . . . 23
4.2.1. Multiple anchoring . . . . . . . . . . . . . . . . . . 23
4.2.2. Dynamic anchor assignment . . . . . . . . . . . . . . 24
4.2.3. Multiple address management . . . . . . . . . . . . . 25
4.3. Combined solutions analysis . . . . . . . . . . . . . . . 26
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 27
6. Security Considerations . . . . . . . . . . . . . . . . . . . 27
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.1. Normative References . . . . . . . . . . . . . . . . . . . 27
7.2. Informative References . . . . . . . . . . . . . . . . . . 28
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 30
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 30
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1. Introduction
The Distributed Mobility Management (DMM) approach aims at setting up
IP networks so that traffic is distributed in an optimal way and does
not rely on centrally deployed anchors to manage IP mobility
sessions.
A first step towards the definition of DMM solutions is the
definition of the problem of distributed mobility management and the
identification of the main requirements for a distributed mobility
management solution [I-D.ietf-dmm-requirements].
We first analyze existing practices of deployment of IP mobility
solutions from a DMM perspective [I-D.perkins-dmm-matrix],
[I-D.patil-dmm-issues-and-approaches2dmm]. After that, a gap
analysis is carried out, identifying what can be achieved with
existing solutions and what is missing in order to meet the DMM
requirements identified in [I-D.ietf-dmm-requirements].
2. Practices: deployment of existing solutions in a DMM fashion
This section documents practices for the deployment of existing
mobility protocols in a distributed mobility management (DMM)
fashion. The scope is limited to existing IPv6-based and 3GPP
mobility protocols, such as Mobile IPv6 [RFC6275], NEMO Basic Support
Protocol [RFC3963], Proxy Mobile IPv6 [RFC5213], 3GPP GPRS Tunnelling
Protocol, and protocol extensions, such as Hierarchical Mobile IPv6
[RFC5380], Mobile IPv6 Fast Handovers [RFC5568], Localized Routing
for Proxy Mobile IPv6 [RFC6705], or 3GPP Selective IP Traffic Offload
(SIPTO), among others [RFC6301].
The section is divided in three parts: IP client-based mobility, IP
network-based mobility and 3GPP mobility solutions.
2.1. Client-based IP mobility
Mobile IPv6 (MIPv6) [RFC6275] and its extension to support mobile
networks, the NEMO Basic Support protocol (hereafter, simply NEMO)
[RFC3963] are well-known client-based IP mobility protocols. They
heavily rely on the function of the Home Agent (HA), a centralized
anchor, to provide mobile nodes (hosts and routers) with mobility
support. We next describe how Mobile IPv6/NEMO and several
additional protocol extensions can be deployed to meet some of the
DMM requirements [I-D.ietf-dmm-requirements].
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2.1.1. Mobile IPv6 / NEMO
<- INTERNET -> <- HOME NETWORK -> <---- ACCESS NETWORK ---->
------- -------
| CN1 | ------- | AR1 |-(o) zzzz (o)
------- | HA1 | ------- |
------- (MN1 anchored at HA1) -------
------- | MN1 |
| AR2 |-(o) -------
-------
-------
| HA2 | -------
------- | AR3 |-(o) zzzz (o)
------- |
------- (MN2 anchored at HA2) -------
| CN2 | ------- | MN2 |
------- | AR4 |-(o) -------
-------
CN1 CN2 HA1 HA2 AR1 MN1 AR3 MN2
| | | | | | | |
|<------------>|<=================+=====>| | | BT mode
| | | | | | | |
| |<----------------------------------------+----->| RO mode
| | | | | | | |
Figure 1: Distributed operation of Mobile IPv6 (BT and RO) / NEMO
Due to the heavy dependence on the home agent role, the base Mobile
IPv6 and NEMO protocols (i.e., without additional extensions) cannot
be easily deployed in a distributed fashion. One approach to
distribute the anchors can be to deploy several HAs (as shown in
Figure 1), and assign to each MN the one closest to its topological
location [RFC4640], [RFC5026], [RFC6611]. In the example shown in
Figure 1, MN1 is assigned HA1 (and a home address anchored by HA1),
while MN2 is assigned HA2. Note that current Mobile IPv6 / NEMO
specifications do not allow the simultaneous use of multiple home
agents by a single mobile node instance, and therefore the benefits
of this deployment model shown here are limited (unless multiple
MIPv6 MN instances are run in parallel, each of them associated to a
different HA). For example, if MN1 moves and attaches to AR3, the
path followed by data packets would be suboptimal, as they have to
traverse HA1, which is no longer close to the topological attachment
point of MN1.
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2.1.2. Mobile IPv6 Route Optimization
One of the main goals of DMM is to avoid the suboptimal routing
caused by centralized anchoring. By default, Mobile IPv6 and NEMO
use the so-called Bidirectional Tunnel (BT) mode, in which data
traffic is always encapsulated between the MN and its HA before being
directed to any other destination. Mobile IPv6 also specifies the
Route Optimization (RO) mode, which allows the MN to update its
current location on the CNs, and then use the direct path between
them. Using the example shown in Figure 1, MN1 is using BT mode with
CN2 and MN2 is in RO mode with CN1. However, the RO mode has several
drawbacks:
o The RO mode is only supported by Mobile IPv6. There is no route
optimization support standardized for the NEMO protocol, although
many different solutions have been proposed.
o The RO mode requires additional signaling, which adds some
protocol overhead.
o The signaling required to enable RO involves the home agent, and
it is repeated periodically because of security reasons [RFC4225].
This basically means that the HA remains as single point of
failure, because the Mobile IPv6 RO mode does not mean HA-less
operation.
o The RO mode requires additional support on the correspondent node
(CN).
Notwithstanding these considerations, the RO mode does offer the
possibility of substantially reducing traffic through the Home Agent,
in cases when it can be supported on the relevant correspondent
nodes.
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2.1.3. Hierarchical Mobile IPv6
<- INTERNET -> <- HOME NETWORK -> <------- ACCESS NETWORK ------->
-----
/|AR1|-(o) zz (o)
-------- / ----- |
| MAP1 |< -------
-------- \ ----- | MN1 |
------- \|AR2| -------
| CN1 | ----- HoA anchored
------- ----- at HA1
------- /|AR3| RCoA anchored
| HA1 | -------- / ----- at MAP1
------- | MAP2 |< LCoA anchored
-------- \ ----- at AR1
\|AR4|
------- -----
| CN2 | -----
------- /|AR5|
-------- / -----
| MAP3 |<
-------- \ -----
\|AR6|
-----
CN1 CN2 HA1 MAP1 AR1 MN1
| | | | ________|__________ |
|<------------------>|<==============>|<________+__________>| HoA
| | | | | |
| |<-------------------------->|<===================>| RCoA
| | | | | |
Figure 2: Hierarchical Mobile IPv6
Hierarchical Mobile IPv6 (HMIPv6) [RFC5380] allows reducing the
amount of mobility signaling as well as improving the overall
handover performance of Mobile IPv6 by introducing a new hierarchy
level to handle local mobility. The Mobility Anchor Point (MAP)
entity is introduced as a local mobility handling node deployed
closer to the mobile node.
When HMIPv6 is used, the MN has two different temporal addresses: the
Regional Care-of Address (RCoA) and the Local Care-of Address (LCoA).
The RCoA is anchored at one MAP, that plays the role of local home
agent, while the LCoA is anchored at the access router level. The
mobile node uses the RCoA as the CoA signaled to its home agent.
Therefore, while roaming within a local domain handled by the same
MAP, the mobile node does not need to update its home agent (i.e.,
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the mobile node does not change RCoA).
The use of HMIPv6 allows some route optimization, as a mobile node
may decide to directly use the RCoA as source address for a
communication with a given correspondent node, notably if the MN does
not expect to move outside the local domain during the lifetime of
the communication. This can be seen as a potential DMM mode of
operation. In the example shown in Figure 2, MN1 is using its global
HoA to communicate with CN1, while it is using its RCoA to
communicate with CN2.
Additionally, a local domain might have several MAPs deployed,
enabling hence different kind of HMIPv6 deployments (e.g., flat and
distributed). The HMIPv6 specification supports a flexible selection
of the MAP (e.g., based on the distance between the MN and the MAP,
taking into consideration the expected mobility pattern of the MN,
etc.).
2.1.4. Home Agent switch
The Home Agent switch specification [RFC5142] defines a new mobility
header for signaling a mobile node that it should acquire a new home
agent. Although the purposes of this specification do not include
the case of changing the mobile node's home address, as that might
imply loss of connectivity for ongoing persistent connections, it
could be used to force the change of home agent in those situations
where there are no active persistent data sessions that cannot cope
with a change of home address.
2.1.5. IP Flow Mobility
There are different specifications meant to support IP Flow Mobility
(IFOM) with Mobile IPv6, namely the multiple care-of address
registration [RFC5648], the flow bindings in Mobile IPv6 and NEMO
[RFC6089] and the traffic selectors for flow bindings [RFC6088]. The
use of these extensions allows a mobile node to associate different
flows with different care-of addresses that the mobile owns at a
given time. This could also be used, combined with the route
optimization support, to improve the paths followed by data packets,
avoiding the traversal of the core network for selected flows.
2.1.6. Source Address Selection
The IPv6 socket API for source address selection [RFC5014], [RFC6724]
can be used by an application running on a mobile node to express its
preference of using a home address or a care-of address in a given
connection. This allows, for example, an application which can
survive an IP address change to always prefer the use of a care-of
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address. Similarly, and as mentioned in [RFC6275], a mobile node can
also prefer the use of a care-of address for sessions that are going
to finish before the mobile node hands off to a different attachment
point (e.g., short-lived connections like DNS dialogs). This could
be based on user or operator policies, and it is typically performed
by a connection manager (e.g., [I-D.seite-mif-cm]).
2.2. Network-based IP mobility
Proxy Mobile IPv6 (PMIPv6) [RFC5213] is the main network-based IP
mobility protocol specified for IPv6. Architecturally, PMIPv6 is
similar to MIPv6, as it relies on the function of the Local Mobility
Anchor (LMA) to provide mobile nodes with mobility support, without
requiring the involvement of the mobile nodes. The required
functionality at the mobile node is provided in a proxy manner by the
Mobile Access Gateway (MAG). We next describe how network-based
mobility protocols and several additional extensions can be deployed
to meet some of the DMM requirements [I-D.ietf-dmm-requirements].
2.2.1. Proxy Mobile IPv6
<- INTERNET -><- HOME NET -><----------- ACCESS NETWORK ------------>
-------
| CN1 | -------- -------- --------
------- -------- | MAG1 | | MAG2 | | MAG3 |
| LMA1 | ---+---- ---+---- ---+----
------- -------- | | |
| CN2 | (o) (o) (o)
------- -------- x x
| LMA2 | x x
------- -------- (o) (o)
| CN3 | | |
------- ---+--- ---+---
Anchored | MN1 | Anchored | MN2 |
at LMA1 -> ------- at LMA2 -> -------
CN1 CN2 LMA1 LMA2 MAG1 MN1 MAG3 MN2
| | | | | | | |
|<------------>|<================>|<---->| | |
| | | | | | | |
| |<------------>|<========================>|<----->|
| | | | | | | |
Figure 3: Distributed operation of Proxy Mobile IPv6
As with Mobile IPv6, plain Proxy Mobile IPv6 operation cannot be
easily decentralized, as in this case there also exists a single
network anchor point. One simple but still suboptimal approach,
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would be to deploy several local mobility anchors and use a
topological position-based assignment to attach mobile nodes (an
example of this type of assignment is shown in Figure 3. This
assignment can be static or dynamic (as described in Section 2.2.3).
The main advantage of this simple approach is that the IP address
anchor (i.e., the LMA) is placed close to the mobile node, and
therefore resulting paths are close-to-optimal. On the other hand,
as soon as the mobile node moves, the resulting path starts to
deviate from the optimal one.
2.2.2. Local Routing
[RFC6705] enables optimal routing in Proxy Mobile IPv6 in three
cases: i) when two communicating MNs are attached to the same MAG and
LMA, ii) when two communicating MNs are attached to different MAGs
but to the same LMA, and iii) when two communicating MNs are attached
to the same MAG but have different LMAs. In these three cases, data
traffic between the two mobile nodes does not traverse the LMA(s),
thus providing some form of path optimization since the traffic is
locally routed at the edge.
The main disadvantage of this approach is that it only tackles the
MN-to-MN communication scenario, and only under certain
circumstances.
In the context of 3GPP, the closest analogy is the use of the X2
interface between two eNBs to directly exchange data traffic during
handover procedures. 3GPP does not foresee the use of local routing
at any other point of the network given the structure of the EPS
bearer model.
2.2.3. LMA runtime assignment
[RFC6463] specifies a runtime local mobility anchor assignment
functionality and corresponding mobility options for Proxy Mobile
IPv6. This runtime local mobility anchor assignment takes place
during the Proxy Binding Update / Proxy Binding Acknowledgment
message exchange between a mobile access gateway and a local mobility
anchor. While this mechanism is mainly aimed for load-balancing
purposes, it can also be used to select an optimal LMA from the
routing point of view. A runtime LMA assignment can be used to
change the assigned LMA of an MN, for example in case when the mobile
node does not have any session active, or when running sessions can
survive an IP address change.
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2.2.4. Source Address Selection
Also in the context of network-based mobility, the use of a source
address selection API can be considered as means to achieve better
routing (by using different anchors). For instance, an MN connected
to a PMIPv6 domain could attach two different wireless network
interfaces to two different MAGs, hence configuring a different set
of HNPs on both interfaces (potentially combining both IPv4 and
IPv6). Based on application requirements or operator's policies the
connection manager logic could instruct the IP stack on the MN to
route selected traffic on a specific wireless interface
[I-D.seite-mif-cm]. It should be noted that source address selection
mostly provides for better routing but not session continuity.
2.2.5. Multihoming in PMIPv6
PMIPv6 provides some multihoming support. RFC 5213 specifies that
the LMA can maintain one mobility session per attached interface and
that upon handover the full set of HNPs can be moved to another
interface in case of inter-technology handover (MAGs providing
different wireless access technology) or maintained on the same
interface in case of intra-technology handover (MAGs providing the
same wireless access technology). An MN can also attach two
different interfaces to the same PMIPv6 domain (as described in
Section 2.2.4), hence resulting in a multihomed device being able to
send/receive traffic sequentially or simultaneously from both network
interfaces. [I-D.ietf-netext-pmipv6-flowmob] extends the base
RFC5213 capabilities so that a mobility session can be shared across
two different access networks. It derives that a selected flow could
be routed through different paths, hence achieving some sort of
better routing. Yet all the traffic is anchored at centralized
anchor points.
2.3. 3GPP mobility
Architecturally, the 3GPP Evolved Packet Core (EPC) network is also
similar to PMIPv6 and MIPv6, as it relies on the Packet Data Gateway
(PGW) anchoring services to provide mobile nodes with mobility
support (see Figure 4). There are client-based and network-based
mobility solutions in 3GPP, which for simplicity we will analyze
together. We next describe how 3GPP mobility protocols and several
additional completed or on-going extensions can be deployed to meet
some of the DMM requirements. [I-D.ietf-dmm-requirements].
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+---------------------------------------------------------+
| PCRF |
+-----------+--------------------------+----------------+-+
| | |
+----+ +-----------+------------+ +--------+-----------+ +-+-+
| | | +-+ | | Core Network | | |
| | | +------+ |S|__ | | +--------+ +---+ | | |
| | | |GERAN/|_|G| \ | | | HSS | | | | | |
| +-----+ UTRAN| |S| \ | | +---+----+ | | | | E |
| | | +------+ |N| +-+-+ | | | | | | | x |
| | | +-+ /|MME| | | +---+----+ | | | | t |
| | | +---------+ / +---+ | | | 3GPP | | | | | e |
| +-----+ E-UTRAN |/ | | | AAA | | | | | r |
| | | +---------+\ | | | SERVER | | | | | n |
| | | \ +---+ | | +--------+ | | | | a |
| | | 3GPP AN \|SGW+----- S5---------------+ P | | | l |
| | | +---+ | | | G | | | |
| | +------------------------+ | | W | | | I |
| UE | | | | | | P |
| | +------------------------+ | | +-----+ |
| | |+-------------+ +------+| | | | | | n |
| | || Untrusted +-+ ePDG +-S2b---------------+ | | | e |
| +---+| non-3GPP AN | +------+| | | | | | t |
| | |+-------------+ | | | | | | w |
| | +------------------------+ | | | | | o |
| | | | | | | r |
| | +------------------------+ | | | | | k |
| +---+ Trusted non-3GPP AN +-S2a--------------+ | | | s |
| | +------------------------+ | | | | | |
| | | +-+-+ | | |
| +--------------------------S2c--------------------| | | |
| | | | | |
+----+ +--------------------+ +---+
Figure 4: EPS (non-roaming) architecture overview
2.3.1. GPRS Tunnelling Protocol (GTP) and DSMIPv6
GPRS Tunnelling Protocol (GTP) [3GPP.29.060] is a network-based
mobility protocol specified for 3GPP networks (S2a, S2b, S5 and S8
interfaces). Similar to PMIPv6, it can handle mobility without
requiring the involvement of the mobile nodes. In this case, the
mobile node functionality is provided in a proxy manner by the
Serving Data Gateway (SGW), Evolved Packet Data Gateway (ePDG), or
Trusted Wireless Access Gateway (TWAG).
3GPP specifications also include client-based mobility support, based
on adopting the use of Dual-Stack Mobile IPv6 (DSMIPv6) [RFC5555] for
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the S2c interface. In this case, the UE implements the mobile node
functionality, while the home agent role is played by the PGW.
2.3.2. Local IP Access and Selected IP Traffic Offload (LIPA-SIPTO)
A Local IP Access (LIPA) and Selected IP Traffic Offload (SIPTO)
enabled network [3GPP.23.829] allows offloading some IP services at
the local access network, above the Radio Access Network (RAN) or at
the macro, without the need to traverse back to the PGW.
Similarly to the runtime local mobility anchor assignment described
in Section 2.2.3, considerations have been discussed in 3GPP with
respect to SIPTO. SIPTO enables an operator to offload certain types
of traffic at a network node close to the UE's point of attachment to
the access network, by selecting a set of GWs (SGW and PGW) that is
geographically/topologically close to the UE's point of attachment.
LIPA, on the other hand, enables an IP capable UE connected via a
Home eNB (HeNB) to access other IP capable entities in the same
residential/enterprise IP network without the user plane traversing
the mobile operator's network core. In order to achieve this, a
Local GW (L-GW) collocated with the HeNB is used. LIPA is
established by the UE requesting a new PDN connection to an access
point name for which LIPA is permitted, and the network selecting the
Local GW associated with the HeNB and enabling a direct user plane
path between the Local GW and the HeNB.
2.3.3. LIPA Mobility and SIPTO at the Local Network (LIMONET)
Both SIPTO and LIPA have a very limited mobility support, specially
in 3GPP specifications up to Rel-10. In Rel-11, there is currently a
work item on LIPA Mobility and SIPTO at the Local Network (LIMONET)
[3GPP.23.859] that is studying how to provide SIPTO and LIPA
mechanisms with some additional, but still limited, mobility support.
In a glimpse, LIPA mobility support is limited to handovers between
HeNBs that are managed by the same L-GW (i.e., mobility within the
local domain), while seamless SIPTO mobility is still limited to the
case where the SGW/PGW is at or above Radio Access Network (RAN)
level.
2.3.4. Data IDentification in ANDSF (DIDA) and Operator Policies for IP
Interface Selection (OPIIS)
There are two ongoing work items in 3GPP that are currently
addressing the issue of selecting a wireless interface or an IP
address for a specific data application. The work item DIDA (Data
IDentification in ANDSF) is addressing the need to map an application
ID to a specific wireless interface, while the work item Operator
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Policies for IP Interface Selection (OPIIS) is addressing the need of
selecting the right APN for a given application.
Taking into account that there is a one to one link between APN and
PDN connection (i.e., IP address) these work items clearly address
from a 3GPP perspective the same problem space as [RFC6724], and the
same considerations described in Section 2.2.4 apply here as well.
2.3.5. Multi-Access PDN Connectivity (MAPCON)
The Multi-Access PDN Connectivity (MAPCON) feature addresses the use
of multiple PDN connections. Hence, this feature can make use of
multiple wireless interfaces either sequentially or simultaneously.
3. Gap Analysis: limitations in current practices
This section identifies the limitations in the current practices
(documented in Section 2) with respect to the requirements listed in
[I-D.ietf-dmm-requirements].
The analysis is divided in three parts: IP client-based mobility, IP
network-based mobility, and 3GPP mobility solutions. Each part
analyzes how well the requirements listed in
[I-D.ietf-dmm-requirements] are covered/met by the current practices,
highlighting existing limitations and gaps.
3.1. Client-based IP mobility
3.1.1. REQ1: Distributed deployment
MIPv6 / NEMO A careful home agent deployment and policy
configuration of the Mobile IPv6 / NEMO protocols can achieve some
distribution. However, as soon as the mobile node moves and
changes its initial attachment point, the anchors are no longer
placed optimally, incurring in sub-optimal routes. This situation
may be acceptable as long as the session is short-lived. If the
mobile node is not expected to move within a limited area, this
configuration might be considered sufficient. Otherwise,
additional mechanisms to support dynamic anchoring would be
needed. Note that a possible solution would be to run multiple
instances of mobile IPv6 at the mobile node, each one managing a
different HoA and bound to a different home agent. This would
require, though, additional intelligence at the mobile node to be
able to optimally select and manage source IP addresses for each
session.
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Mobile IPv6 RO The use of route optimization support enables a
close-to anchor-less operation, which effectively can be
considered as a fully distributed configuration. However, as
explained before in this document, the home agent is still used
for the signaling and therefore remains as a critical centralized
component. Additionally, there is no standardized RO support for
network mobility.
HMIPv6 The use of hierarchical mobile IPv6 can be seen as a step
forward compared to a careful deployment of multiple home agents
and its proper configuration, as it allows a mobile node to roam
within a local domain, reducing the handover latency as well as
the signaling overhead. If used together with mobile IPv6,
traffic still has to traverse the centralized home agent, and
therefore no distributed operation is achieved.
HA switch The home agent switch specification can be used to enable
obtaining more benefits from a multiple-HA deployment, as the
mobile node could be instructed to switch to a closer home agent.
To avoid packet loss, this switch must be performed at periods of
time in which the mobile node does not have any active connection
running. Even if some packet loss were acceptable for active
sessions, the change of home address would also require the mobile
node to re-establish those sessions.
Flow mobility Considerations made for previous scenarios (e.g. for
Route Optimization) could also apply here, extending those
scenarios by the use of multiple attached interfaces.
SA selection API The use of proper source address selection
decisions, enabled by smart connection managers
[I-D.seite-mif-cm], or mobility aware applications using a
selection API [RFC5014], [RFC6724], would allow the mobile node to
realize substantial benefits from deployments providing multiple
anchors.
3.1.2. REQ2: Transparency to Upper Layers when needed
MIPv6 / NEMO As a mobility protocol, the solution is transparent to
the upper layers. However, as described before, this transparency
comes with the cost of suboptimal routes if the MN moves away from
its initial attachment point.
Mobile IPv6 RO The use of the route optimization support is
transparent to the upper layers.
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HMIPv6 The use of HMIPv6 is transparent to the upper layers.
HA switch The use of the home agent switch functionality is not
transparent to the upper layers, as a change of home agent
normally implies a change of home address. Therefore, the home
agent can only be switched when there is no active session running
on the mobile node. Since IP address continuity cannot be
achieved at the relocated home agents, one gap that would need to
be filled is the ability for the mobile node to convey HoA context
from the previous home agent.
Flow mobility The use of flow mobility mechanisms is transparent to
the upper layers.
SA selection API The use of an intelligent source address mechanisms
is transparent to the upper layers if performed by the connection
manager. However if the selection is performed by the
applications themselves, via the use of the API, then applications
have to be mobility-aware.
3.1.3. REQ3: IPv6 deployment
MIPv6 / NEMO Mobile IPv6 / NEMO protocols primarily support IPv6,
although there are some extensions defined to also offer some IPv4
support [RFC5555].
Mobile IPv6 RO Route optimization only supports IPv6.
HMIPv6 HMIPv6 is only defined for IPv6.
HA switch The home agent switch specification supports only IPv6,
although the use of the defined mechanisms to support dual stack
IPv4/IPv6 mobile nodes would also enable some IPv4 support.
Flow mobility Flow mobility is only defined for IPv6.
SA selection API The use of source address selection mechanisms
supports both IPv6 and IPv4.
3.1.4. REQ4: Existing mobility protocols
MIPv6 / NEMO These approaches are ones of the base IETF-standardized
mobility protocols: [RFC6275] and [RFC3963].
Mobile IPv6 RO This approach is based on an existing protocol
[RFC6275].
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HMIPv6 This approach is based on an existing protocol [RFC5380].
HA switch This approach is based on an existing protocol [RFC5142].
Flow mobility This approach is based on existing protocols
[RFC5648], [RFC6089] and [RFC6088].
SA selection API This approach is based on existing protocols
[RFC6724] and [RFC5014].
3.1.5. REQ5: Compatibility
MIPv6 / NEMO This approach would be compatible with other protocols
and work between trusted administrative domains, although as
described before its operation would not provide the benefits of a
fully distributed mechanism. The combination of different IP
mobility protocols might have a performance/complexity cost
associated, as described in [A. de la Oliva, et al.].
Mobile IPv6 RO This approach would be compatible with other
protocols and work between trusted administrative domains, as long
as mobile IPv6 is allowed. However, as highlighted before, mobile
IPv6 route optimization requires specific support at the
correspondent nodes.
HMIPv6 HMIPv6 is compatible with other protocols.
HA switch This approach would be compatible with other protocols and
work between trusted administrative domains.
Flow mobility This approach would be compatible with other protocols
and work between trusted administrative domains.
SA selection API This approach has no impact in terms of
compatibility or use between trusted administrative domains.
3.1.6. REQ6: Security considerations
MIPv6 / NEMO This approach includes security considerations.
Mobile IPv6 RO This approach includes security considerations.
HMIPv6 This approach includes security considerations.
HA switch This approach includes security considerations.
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Flow mobility This approach includes security considerations.
SA selection API This approach does not have security issues.
3.2. Network-based IP mobility
3.2.1. REQ1: Distributed deployment
PMIPv6 As for the case of MIPv6, a careful deployment of the local
mobility anchors and policy configuration of the Proxy Mobile IPv6
protocol can achieve some distribution. However, as soon as the
mobile node moves and changes its initial attachment point, the
anchor is no longer placed optimally, incurring in sub-optimal
routes, which might be quite noticeable in case of medium to large
PMIPv6 domains. If the mobile node movement is restricted to a
well known limited area and/or the PMIPv6 domain is not large,
this configuration might be considered sufficient. Otherwise,
additional mechanisms to support dynamic anchoring would be
needed.
Local Routing As mentioned before, it enables optimal routing in
three cases: the LMA manages the traffic of two mobile nodes
connected to the same MAG, the LMA manages the traffic of two
mobile nodes connected to different MAGs, the MAG manages the
traffic of two mobile nodes connected to different LMAs. LR does
not consider the case where the traffic should be optimized
considering different MAGs and different LMAs. Inter LMA
communication is not in scope. LR only enables better routing and
does not consider the distribution of mobility anchors as such.
LMA Runtime Assignment The LMA runtime assignment is used to
allocate an optimal LMA mostly for load balancing purposes, for
instance in scenarios where LMAs run in a datacenter-like
infrastructure. It can be used to allocate a different LMA based
on other policies such as routing, although it is not clear how
the technology can be used to achieve distributed mobility
management, especially considering scalability issues. There are
different gaps that would prevent using this mechanism as a way to
meet all the DMM requirements: i) LMA runtime assignment can only
performed at the MN's attachment, so it would need to be extended
to allow LMA re-location at any time; ii) LMA runtime assignment
can only be initiated by current LMA; iii) it is not in the scope
of the specification how the context is transferred between the
involved LMAs.
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Source Address Selection It can help in selecting a given IP source
address although the current specifications have many limitations
(for instance prefer IPv6 over IPv4, prefer HoA instead of CoA)
and the socket extensions [RFC5014] require changes in the node.
This solution alone is not sufficient to achieve anchors
distribution in case of session continuity requirements, as some
control logic (e.g., from a connection manager [I-D.seite-mif-cm])
is needed to intelligently perform source address selection.
Multihoming in PMIPv6 As summarized in the previous section a single
mobility session belongs to a single LMA (at the most the same
mobility session is shared across two access networks). As of
today there is no possibility to distribute anchors and to move
the session between different LMAs.
3.2.2. REQ2: Transparency to Upper Layers when needed
PMIPv6 As a mobility protocol, the solution provides transparent
mobility support for a mobile node while roaming within the PMIPv6
domain (e.g., if a mobile node moves outside the domain,
established sessions cannot be maintained, unless the MN
implements Mobile IPv6). However, as for the MIPv6 case, this
transparent mobility support comes with the cost of suboptimal
routes if the MN moves away from its initial attachment point,
especially in large PMIPv6 domains.
Local Routing During HO the standard mechanisms are used. In this
sense if there is a MAG change while LR is enabled signaling is
exchanged to inform the target MAG that upon handover LR should be
re-established. The inter LMA case is not supported. For this
solution the mobility context is always up, all the traffic
receive seamless service.
LMA Runtime Assignment Seamless support is provided as per RFC 5213.
Since the LMA cannot be changed at runtime, the solution provides
transparency to the upper layers. However, if the solution were
extended to allow dynamic LMA re-location, some extensions would
be needed to provide IP address continuity.
Source Address Selection No seamless support is currently provided,
since it requires solutions such as IP flow mobility for PMIPv6
[I-D.ietf-netext-pmipv6-flowmob].
Multihoming in PMIPv6 Seamless support falls back to standard PMIPv6
operations extended for IP flow mobility support. For this
solution the mobility context is always up, all the traffic
receive seamless service.
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3.2.3. REQ3: IPv6 deployment
PMIPv6 Although Proxy Mobile IPv6 primarily support IPv6, there are
also extensions defined to also offer some limited IPv4 support
[RFC5844].
Local Routing It supports both IPv4 (limited to the support provided
by [RFC5844]) and IPv6.
LMA Runtime Assignment It supports both IPv4 (limited to the support
provided by [RFC5844]) and IPv6.
Source Address Selection It supports both IPv4 and IPv6.
Multihoming in PMIPv6 It supports both IPv4 (limited to the support
provided by [RFC5844]) and IPv6.
3.2.4. REQ4: Existing mobility protocols
PMIPv6 This approach is one of the base IETF-standardized mobility
protocols: [RFC5213].
Local Routing It reuses [RFC5213].
LMA Runtime Assignment It reuses [RFC5213].
Source Address Selection This approach is based on local support on
the terminal only.
Multihoming in PMIPv6 It reuses [RFC5213].
3.2.5. REQ5: Compatibility
PMIPv6 This protocol is compatible with other protocols and can
operate between trusted administrative domains, although there may
be an associated penalty in terms of performance and/or complexity
[A. de la Oliva, et al.].
Local Routing Since it extends [RFC5213], compatibility with
existing network deployments and end hosts is provided.
LMA Runtime Assignment Since it extends [RFC5213], compatibility
with existing network deployments and end hosts is provided.
Source Address Selection To enable the full set of use cases
mentioned above extensions are required thus impacting the
landscape of mobile devices. The extensions should not impact the
network.
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Multihoming in PMIPv6 Since it extends [RFC5213], compatibility is
provided.
3.2.6. REQ6: Security considerations
PMIPv6 This approach includes security considerations.
Local Routing It reuses [RFC5213]. As such, the same security
considerations apply.
LMA Runtime Assignment It reuses [RFC5213]. As such, the same
security considerations apply.
Source Address Selection There is not signaling involved to perform
this action.
Multihoming in PMIPv6 It reuses [RFC5213]. As such, the same
security considerations apply.
3.3. 3GPP mobility
3.3.1. REQ1: Distributed deployment
SIPTO enables a certain degree of distribution, as SGW/PGW can be
selected to be the closest geographically to the UE. This, together
with the use of OPIIS (and MAPCON for the case the UE is using
multiple interfaces), could be used to allow the use of different
anchors as the UE moves. However, as described below, there is no
support for dynamically changing the anchor while providing IP
address continuity, which might be OK for short-lived sessions.
3.3.2. REQ2: Transparency to Upper Layers when needed
Seamless mobility at the local network is still not considered in
SIPTO. Therefore, although SIPTO and LIPA allow offloading traffic
from the network core similarly to the DMM approaches, even with
LIMONET they just provide localized mobility support, requiring
packet data network connections to be deactivated and re-activated
when the UE is not moving locally.
3.3.3. REQ3: IPv6 deployment
3GPP specs support IPv6 as described in [RFC6459].
3.3.4. REQ4: Existing mobility protocols
Current 3GPP specifications make use of both IETF standardized
mechanisms (e.g., PMIPv6, DSMIPv6), and custom made mechanisms, such
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as GTP.
3.3.5. REQ5: Compatibility
All the 3GPP extensions listed in this document are compatible with
3GPP networks, at least for the same release these extensions are
introduced or newer ones.
3.3.6. REQ6: Security considerations
3GPP extensions are assumed to be secure. TBD: refine (possibly
extending) this section.
4. Conclusions
In this section we identify the gaps between existing mobility
solutions and the DMM requirements and expected functionalities. We
first summarize the identified IP-mobility protocols and provide a
mapping (e.g., YES, NO, LIMITED) to the different DMM requirements
listed in [I-D.ietf-dmm-requirements]. Following the independent
analysis, a comparison between the solutions and the main DMM
functionalities is provided. Finally, the possibility of using
multiple solutions is addressed by combining different solutions
according to the results found in the independent and functional
analysis.
4.1. Independent solution analysis
+-------------+------+------+-----------+------+------+------+
| | REQ1 | REQ2 | REQ3 | REQ4 | REQ5 | REQ6 |
+-------------+------+------+-----------+------+------+------+
| MIPv6/NEMO | NO | LIM | v6/v4 | YES | LIM | YES |
| MIPv6 RO | NO | YES | v6 | YES | LIM | YES |
| HMIPv6 | NO | YES | v6 | YES | LIM | YES |
| HA switch | NO | NO | v6 | YES | YES | YES |
| FlowMob | NO | YES | v6/LIM v4 | YES | YES | YES |
| SAS w/ CB | NO | YES | v6/v4 | YES | YES | YES |
| PMIPv6 | NO | LIM | v6/LIM v4 | YES | LIM | YES |
| LR | NO | LIM | v6/LIM v4 | YES | YES | YES |
| LMA RA | LIM | LIM | v6/LIM v4 | YES | YES | YES |
| SAS w/ NB | NO | NO | v6/v4 | YES | YES | YES |
| MuHo PMIPv6 | NO | LIM | v6/LIM v4 | YES | YES | YES |
+-------------+------+------+-----------+------+------+------+
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4.2. Functional analysis
The goal of this section is to identify and analyze the main
functions that a DMM solution should provide in order to meet the DMM
requirements [I-D.ietf-dmm-requirements]. This analysis is on
purpose kept at high level, and will be used in the following section
as main guideline for the final assessment of the gaps that cannot be
covered with existing specified and deployed solutions (even if
combined).
4.2.1. Multiple anchoring
Multiple (distributed) anchoring refers to the ability to anchor
different sessions of a single mobile node at different anchors. In
order to make this feature "DMM-friendly", some anchors should be
placed closer to the mobile node. This implies the ability to deploy
routers and assign locally anchored IP addresses at the edge of the
network. This feature also requires potentially assigning multiple
IP addresses to a single mobile node for its simultaneous use.
Figure 5 shows an example of the multiple anchoring function, in
which a mobile network operator (MNO) has deployed multiple anchors,
placed closer to or at the access network level. These (distributed)
anchors provide attaching terminals with IP addresses that are
locally anchored, allowing MNs' traffic (Internet and operator
services) to be locally offloaded (i.e., not traversing the MNO's
core).
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+-----+ +-----+
| CN1 | | CN2 |
+-----+ +-----+
| |
+--------------------+
( )
( Internet )
( )
+--------------------+
||
+------------------------------------------------+
( )
( -------------------- )
( | centralized | Mobile Network )
( | anchor (e.g., | Operator's )
( | LMA/HA/PGW/GGSN) | core )
( -------------------- )
( )
+------------------------------------------------+
/ | \
/ * Internet | x Internet \ + Internet
/ * / access | x / access \ + / access
/ * / | x / \ + /
--+------+----- ----+-----+---- ------+---+----
| distributed | * * *| distributed | | distributed |
| anchor 1 | | anchor i | | anchor n |
---+----------- ---+----------- ---+-----------
| | |
(o) (o) (o)
session * x session + session
anchored * x anchored + anchored
at 1 * x at i + at n
(o) (o)
| |
+--+--+ +--+--+
| MN1 | | MN2 |
+-----+ +-----+
Figure 5: Multiple anchoring
4.2.2. Dynamic anchor assignment
Dynamic anchor re-location is the ability to i) optimally assign
initial anchor, and ii) change the initially assigned anchor and/or
assign a new one. This can be achieved either by changing anchor for
all ongoing sessions (which might only be achievable with routing-
based solutions), or by assigning new anchors for new sessions.
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Figure 6 shows an example of what the dynamic anchor assignment
function provides. A mobile node MN1, initially attached to the
distributed anchor 1, establishes a session X (anchored at 1, i.e.,
optimal initial anchor assignment), which finishes before MN1 moves
to the distributed anchor i. While connected to the distributed
anchor i, a new session Y is established, which is anchored at i
(i.e. assignment of a new anchor). Then MN1 moves and attaches to
the distributed anchor n, while having session Y active, where MN1 is
assigned n as its anchor for new sessions and (optionally) existing
sessions are moved (i.e., change of assigned anchor).
( )
+------------------------------------------------+
/ | \
/ * Internet | x Internet \ x Internet
/ * / access | x / access \ x / access
/ * / | x / \ x /
--+------+----- ----+----+----- ------+---+----
| distributed | | distributed | | distributed |
| anchor 1 | | anchor i | | anchor n |
---+----------- ---+----------- ---+-----------
| | |
(o) (o) (o)
* x session Y x session Y
session X * x anchored x anchored
anchored * x at i x (moved)
at 1 (o) (o) at n
| |
+--+--+ \ +--+--+
| MN1 | =========) | MN1 |
+-----+ / +-----+
Figure 6: Dynamic anchor assignment
4.2.3. Multiple address management
Multiple IP address management refers to the ability of the mobile
node to simultaneously use multiple IP addresses and select the best
one (from an anchoring point of view) to use on a per-session/
application/service basis. Depending on the mobile node support,
this functionality might require more or less support from the
network side.
Figure 7 shows an example of multiple address management, in which
MN1 initially obtained an IP address (IP a) when connected to the
distributed anchor 1, which is then used for a session which remains
active after MN1 moves and attaches to the distributed anchor i. MN1
also obtains a new IP address (IP b) to be used for sessions
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initiated while attached to i. MN1 therefore needs to simultaneously
manage and use multiple IP addresses, selecting the best one for each
session. This selection might be performed by the mobile node solely
or might be aided/performed with network support.
( )
+------------------------------------------------+
/ | \
/ * Internet | x Internet \ Internet
/ * / access | x / access \ / access
/ * / (IP a) | x / (IP b) \ /
--+------+----- ----+-----+---- ------+---+----
| distributed | * * *| distributed | | distributed |
| anchor 1 | | anchor i | | anchor n |
---+----------- ---+----------- ---+-----------
| | |
(o) (o) (o)
session X * x session Y
anchored * x anchored
at 1 * x at i
(IP a) (o) (IP b)
|
+--+--+
| MN1 |
+-----+
Figure 7: Multiple address management
4.3. Combined solutions analysis
The goal of this section is to evaluate how a solution based on
combining the different standardized IP mobility solutions could meet
the DMM requirements, making reference to the high-level functions
identified above.
Both the main client- and network-based IP mobility protocols, namely
(DS)MIPv6 and PMIPv6 allows to deploy multiple anchors (i.e., home
agents and localized mobility anchors), therefore providing the
functionality of multiple anchoring. However, existing solutions
does only provide an optimal initial anchor assignment, a gap being
the lack of dynamic anchor change/new anchor assignment. Neither the
HA switch nor the LMA runtime assignment allow changing the anchor
during an ongoing session.
Even if dynamic anchor change and new anchor assignment were
supported, default address selection mechanisms would need to be
improved, as mobile nodes would likely be assigned multiple IP
addresses, anchored at different places. Therefore, smart address
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selection, trying to always use the shortest path, would be required.
5. IANA Considerations
No IANA considerations.
6. Security Considerations
This is an informational document that analyzes practices for the
deployment of existing mobility protocols in a distributed mobility
management environment, and identifies the limitations in the current
practices. One of the requirements that these practices has to meet
is to take into account security aspects, including confidentiality
and integrity. This is briefly analyzed for each of the considered
practices, and will be extended in future versions of this document.
7. References
7.1. Normative References
[RFC3963] Devarapalli, V., Wakikawa, R., Petrescu, A., and P.
Thubert, "Network Mobility (NEMO) Basic Support Protocol",
RFC 3963, January 2005.
[RFC5026] Giaretta, G., Kempf, J., and V. Devarapalli, "Mobile IPv6
Bootstrapping in Split Scenario", RFC 5026, October 2007.
[RFC5142] Haley, B., Devarapalli, V., Deng, H., and J. Kempf,
"Mobility Header Home Agent Switch Message", RFC 5142,
January 2008.
[RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.
[RFC5380] Soliman, H., Castelluccia, C., ElMalki, K., and L.
Bellier, "Hierarchical Mobile IPv6 (HMIPv6) Mobility
Management", RFC 5380, October 2008.
[RFC5555] Soliman, H., "Mobile IPv6 Support for Dual Stack Hosts and
Routers", RFC 5555, June 2009.
[RFC5568] Koodli, R., "Mobile IPv6 Fast Handovers", RFC 5568,
July 2009.
[RFC5648] Wakikawa, R., Devarapalli, V., Tsirtsis, G., Ernst, T.,
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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.
[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.
[RFC6463] Korhonen, J., Gundavelli, S., Yokota, H., and X. Cui,
"Runtime Local Mobility Anchor (LMA) Assignment Support
for Proxy Mobile IPv6", RFC 6463, February 2012.
[RFC6611] Chowdhury, K. and A. Yegin, "Mobile IPv6 (MIPv6)
Bootstrapping for the Integrated Scenario", RFC 6611,
May 2012.
[RFC6705] Krishnan, S., Koodli, R., Loureiro, P., Wu, Q., and A.
Dutta, "Localized Routing for Proxy Mobile IPv6",
RFC 6705, September 2012.
[RFC6724] Thaler, D., Draves, R., Matsumoto, A., and T. Chown,
"Default Address Selection for Internet Protocol Version 6
(IPv6)", RFC 6724, September 2012.
7.2. Informative References
[3GPP.23.829]
3GPP, "Local IP Access and Selected IP Traffic Offload
(LIPA-SIPTO)", 3GPP TR 23.829 10.0.1, October 2011.
[3GPP.23.859]
3GPP, "LIPA Mobility and SIPTO at the Local Network", 3GPP
TR 23.859 0.5.0, June 2012.
[3GPP.29.060]
3GPP, "General Packet Radio Service (GPRS); GPRS
Tunnelling Protocol (GTP) across the Gn and Gp interface",
3GPP TS 29.060 3.19.0, March 2004.
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Internet-Draft DMM Gap Analysis December 2012
[A. de la Oliva, et al.]
de la Oliva, A., Soto, I., Calderon, M., Bernardos, C.,
and M. Sanchez, "The costs and benefits of combining
different IP mobility standards", Computer Standards &
Interfaces, accepted for publication, doi:10.1016/
j.csi.2012.08.003 , 2012.
[I-D.ietf-dmm-requirements]
Chan, A., "Requirements for Distributed Mobility
Management", draft-ietf-dmm-requirements-02 (work in
progress), September 2012.
[I-D.ietf-netext-pmipv6-flowmob]
Bernardos, C., "Proxy Mobile IPv6 Extensions to Support
Flow Mobility", draft-ietf-netext-pmipv6-flowmob-05 (work
in progress), October 2012.
[I-D.patil-dmm-issues-and-approaches2dmm]
Patil, B., Williams, C., and J. Korhonen, "Approaches to
Distributed mobility management using Mobile IPv6 and its
extensions", draft-patil-dmm-issues-and-approaches2dmm-00
(work in progress), March 2012.
[I-D.perkins-dmm-matrix]
Perkins, C., Liu, D., and W. Luo, "DMM Comparison Matrix",
draft-perkins-dmm-matrix-04 (work in progress), July 2012.
[I-D.seite-mif-cm]
Seite, P. and J. Zuniga, "MIF API Conn Mngr
Considerations", draft-seite-mif-cm-00 (work in progress),
September 2012.
[RFC4225] Nikander, P., Arkko, J., Aura, T., Montenegro, G., and E.
Nordmark, "Mobile IP Version 6 Route Optimization Security
Design Background", RFC 4225, December 2005.
[RFC4640] Patel, A. and G. Giaretta, "Problem Statement for
bootstrapping Mobile IPv6 (MIPv6)", RFC 4640,
September 2006.
[RFC5014] Nordmark, E., Chakrabarti, S., and J. Laganier, "IPv6
Socket API for Source Address Selection", RFC 5014,
September 2007.
[RFC6301] Zhu, Z., Wakikawa, R., and L. Zhang, "A Survey of Mobility
Support in the Internet", RFC 6301, July 2011.
[RFC6459] Korhonen, J., Soininen, J., Patil, B., Savolainen, T.,
Zuniga, et al. Expires June 22, 2013 [Page 29]
Internet-Draft DMM Gap Analysis December 2012
Bajko, G., and K. Iisakkila, "IPv6 in 3rd Generation
Partnership Project (3GPP) Evolved Packet System (EPS)",
RFC 6459, January 2012.
Appendix A. Acknowledgments
The work of Carlos J. Bernardos and Telemaco Melia has been partially
supported by the European Community's Seventh Framework Programme
(FP7-ICT-2009-5) under grant agreement n. 258053 (MEDIEVAL project).
The work of Carlos J. Bernardos has also been partially supported by
the Ministry of Science and Innovation of Spain under the QUARTET
project (TIN2009-13992-C02-01). The authors would like to thank
Konstantinos Pentikousis, Georgios Karagiannis, Jouni Korhonen, Jong-
Hyouk Lee, Marco Liebsch, Elena Demaria, Peter McCann, Luo Wen and
Julien Laganier for their valuable comments.
Authors' Addresses
Juan Carlos Zuniga
InterDigital Communications, LLC
1000 Sherbrooke Street West, 10th floor
Montreal, Quebec H3A 3G4
Canada
Email: JuanCarlos.Zuniga@InterDigital.com
URI: http://www.InterDigital.com/
Carlos J. Bernardos
Universidad Carlos III de Madrid
Av. Universidad, 30
Leganes, Madrid 28911
Spain
Phone: +34 91624 6236
Email: cjbc@it.uc3m.es
URI: http://www.it.uc3m.es/cjbc/
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Telemaco Melia
Alcatel-Lucent Bell Labs
Route de Villejust
Nozay, Ile de France 91620
France
Email: telemaco.melia@alcatel-lucent.com
Charles E. Perkins
Futurewei
USA
Email: charliep@computer.org
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