wdiff rfc7333.original rfc7333.txt

Network Working Group
Internet Engineering Task Force (IETF) H. Chan (Ed.)
Internet-Draft Chan, Ed.
Request for Comments: 7333 Huawei Technologies
Intended status:
Category: Informational D. Liu
Expires: December 7, 2014
ISSN: 2070-1721 China Mobile
P. Seite
Orange
H. Yokota
KDDI Lab
Landis+Gyr
J. Korhonen
Broadcom Communications
June 5,
August 2014

Requirements for Distributed Mobility Management
draft-ietf-dmm-requirements-17

Abstract

This document defines the requirements for Distributed Mobility
Management (DMM) at the network layer. The hierarchical structure in
traditional wireless networks has led primarily to centrally deployed
mobility anchors. As some wireless networks are evolving away from
the hierarchical structure, it can be useful to have a distributed
model for mobility management in which traffic does not need to
traverse centrally deployed mobility anchors far from the optimal
route. The motivation and the problems addressed by each requirement
are also described.

Requirements Language

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].

Status of this This Memo

This Internet-Draft document is submitted in full conformance with the
provisions of BCP 78 and BCP 79.

Internet-Drafts are working documents not an Internet Standards Track specification; it is
published for informational purposes.

This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
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Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a maximum candidate for any level of Internet
Standard; see Section 2 of RFC 5741.

Information about the current status of six months this document, any errata,
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This Internet-Draft will expire on December 7, 2014.
http://www.rfc-editor.org/info/rfc7333.

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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 ....................................................2
2. Conventions used Used in this document . . . . . . . . . . . . . . 5 This Document ...............................4
2.1. Requirements Language ......................................4
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5 ................................................4
3. Centralized versus distributed mobility management . . . . . . 7 Distributed Mobility Management ..............5
3.1. Centralized mobility management . . . . . . . . . . . . . 7 Mobility Management ............................6
3.2. Distributed mobility management . . . . . . . . . . . . . 8 Mobility Management ............................7
4. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 9 ...............................................8
5. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 11 ...................................................10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 17 ........................................16
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 17
9. ...................................................17
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 20
9.1. .....................................................20
8.1. Normative References . . . . . . . . . . . . . . . . . . . 20
9.2. ......................................20
8.2. Informative References . . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 23 ....................................21

1. Introduction

In the past decade decade, a fair number of network-layer mobility protocols
have been standardized [RFC6275] [RFC5944] [RFC5380] [RFC6301]
[RFC5213]. Although these protocols differ in terms of functions and
associated message formats, they all employ a mobility anchor to
allow a mobile node to remain reachable after it has moved to a
different network. The anchor point, among Among other tasks, tasks that the anchor point performs,
the anchor point ensures connectivity by forwarding packets destined
to, or sent from, the mobile node. It is a centrally deployed
mobility anchor in the sense that the deployed architectures today
have a small number of these anchors and the traffic of millions of
mobile nodes in an operator network are is typically managed by the same
anchor. Such a mobility anchor may still have to reside in the
subscriber's provider network even when the subscriber is roaming to
a visited network, in order that certain functions such as charging
and billing can be performed more readily by the provider's network.
An example provider network is a Third Generation Partnership Project
(3GPP) network.

Distributed mobility management (DMM) is an alternative to the above above-
mentioned centralized deployment. The background behind the interests to study interest
in studying DMM are is primarily in the following. as follows.

(1) Mobile users are, more More than ever, mobile users are consuming Internet content content,
including that of local Content Delivery Networks (CDNs). Such
traffic imposes new requirements on mobile core networks for
data traffic delivery. To prevent exceeding the available core
network capacity, service providers need to implement new
strategies such as selective IPv4 traffic offload (e.g.,
[RFC6909], 3GPP work items Local IP Access (LIPA) and Selected IP Traffic
Offload (SIPTO) work items [TS.23.401]) through alternative
access networks such as Wireless Local Area Network (WLAN)
[Paper-Mobile.Data.Offloading]. Networks (WLANs)
[MOB-DATA-OFFLOAD]. In addition, a gateway selection mechanism
takes the user proximity into account within the Evolved Packet Core
(EPC) [TS.29303]. Yet [TS.29.303]. However, these mechanisms were not pursued
in the past past, owing to charging and billing considerations which that
require solutions beyond the mobility protocol. Consequently,
assigning a gateway anchor node from a visited network when
roaming to the visited network has only recently been done and
is limited to voice services.

Both traffic offloading and CDN mechanisms could benefit from
the development of mobile architectures with fewer hierarchical
levels introduced into the data path by the mobility management
system. This trend of "flattening" the mobile networks works
best for direct communications among peers in the same
geographical area. Distributed mobility management in the
flattening mobile networks would anchor the traffic closer to
the point of attachment of the user.

(2) Today's mobile networks present service providers with new
challenges. Mobility patterns indicate that mobile nodes often
remain attached to the same point of attachment for considerable
periods of time [Paper-Locating.User]. [LOCATING-USER]. Specific IP mobility
management support is not required for applications that launch
and complete their sessions while the mobile node is connected
to the same point of attachment. However, currently, IP mobility support
is currently designed for always-on operation, maintaining all
parameters of the context for each mobile subscriber for as long
as they are connected to the network. This can result in a
waste of resources and unnecessary costs for the service
provider. Infrequent node mobility coupled with application
intelligence suggest that mobility support could be provided selectively such
selectively, e.g., as described in [I-D.bhandari-dhc-class-based-
prefix] [DHCPv6-CLASS-BASED-PREFIX]
and [I-D.korhonen-6man-prefix-properties], [IPv6-PREFIX-PROPERTIES], thus reducing the amount of
context maintained in the network.

DMM may distribute the mobility anchors in the data-plane data plane in
flattening the mobility network such that the mobility anchors are
positioned closer to the user; ideally, mobility agents could be
collocated with the first-hop router. Facilitated by the
distribution of mobility anchors, it may be possible to selectively
use or not use mobility protocol support support, depending on whether such
support is needed or not. It DMM can thus reduce the amount of state
information that must be maintained in various mobility agents of the
mobile network. It network and can then avoid the unnecessary establishment of
mechanisms to forward traffic from an old mobility anchor to a new
mobility anchor.

This document compares distributed mobility management with
centralized mobility management in Section 3. The problems that can
be addressed with DMM are summarized in Section 4. The mandatory
requirements as well as the optional requirements for network-layer
distributed mobility management are given in Section 5. Finally,
security Security
considerations are discussed mentioned in Section 6.

The problem statement and the use cases [I-D.yokota-dmm-scenario] [DMM-SCENARIO] can be found in [Paper-Distributed.Mobility.Review].
[DIST-MOB-REVIEW].

2. Conventions used Used in This Document

2.1. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document

2.1. are to be interpreted as described in RFC 2119 [RFC2119].

2.2. Terminology

All of the general mobility-related terms terms, and their acronyms as used
in this document document, are to be interpreted as defined in the Mobile IPv6
base specification [RFC6275], in the Proxy mobile Mobile IPv6 (PMIPv6)
specification [RFC5213], and in Mobility "Mobility Related Terminology Terminology"
[RFC3753]. These terms include the following: mobile node (MN),
correspondent node (CN), and home agent (HA) as per [RFC6275]; local
mobility anchor (LMA) and mobile access gateway (MAG) as per [RFC5213],
[RFC5213]; and context as per [RFC3753].

In addition, this draft document introduces the following terms. terms:

Centrally deployed mobility anchors

refer

refers to the mobility management deployments in which there are
very few mobility anchors and the traffic of millions of mobile
nodes in an operator network are is managed by the same anchor.

Centralized mobility management

makes use of centrally deployed mobility anchors.

Distributed mobility management

is not centralized centralized, so that traffic does not need to traverse
centrally deployed mobility anchors far from the optimal route.

Hierarchical mobile network

has a hierarchy of network elements arranged into multiple
hierarchical levels which that are introduced into the data path by the
mobility management system.

Flattening mobile network

refers to the hierarchical mobile network which that is going through
the trend of reducing its number of hierarchical levels.

Flatter mobile network

has fewer hierarchical levels compared to a hierarchical mobile
network.

Mobility context

is the collection of information required to provide mobility
management support for a given mobile node.

3. Centralized versus distributed mobility management Distributed Mobility Management

Mobility management is needed because the IP address of a mobile node
may change as the node moves. Mobility management functions may be
implemented at different layers of the protocol stack. At the IP
(network) layer, mobility management can be client-based or network-
based.
network-based.

An IP-layer mobility management protocol is typically based on the
principle of distinguishing between a session identifier and a
forwarding address and maintaining a mapping between the two. In
Mobile IP, the new IP address of the mobile node after the node has
moved is the forwarding address, whereas the original IP address
before the mobile node moves serves as the session identifier. The
location management (LM) information is kept by associating the
forwarding address with the session identifier. Packets addressed to
the session identifier will first route to the original network network,
which
re-directs redirects them using the forwarding address to deliver to the
session. Re-directing Redirecting packets this way can result in long routes. An
existing optimization routes directly directly, using the forwarding address
of the host, and as such is a host-based solution.

The next two subsections explain centralized and distributed mobility
management functions in the network.

3.1. Centralized mobility management Mobility Management

In centralized mobility management, the location information in terms
of a mapping between the session identifier and the forwarding
address is kept at a single mobility anchor, and packets destined to
the session identifier are forwarded via this anchor. In other
words, such mobility management systems are centralized in both the
control plane and the data plane (mobile node IP traffic).

Many existing mobility management deployments make use of centralized
mobility anchoring in a hierarchical network architecture, as shown
in Figure 1. Examples are the home agent (HA) and local mobility
anchor (LMA) serving as the anchors for the mobile node (MN) and
Mobile Access Gateway
mobile access gateway (MAG) in Mobile IPv6 [RFC6275] and in Proxy
Mobile IPv6 [RFC5213] [RFC5213], respectively. Cellular networks networks, such as the 3GPP
General Packet Radio System (GPRS) networks and 3GPP Evolved Packet
System (EPS) networks networks, also employ centralized mobility management
too. management.
In the 3GPP GPRS network, the Gateway GPRS Support Node (GGSN),
Serving GPRS Support Node (SGSN) (SGSN), and Radio Network Controller (RNC)
constitute a hierarchy of anchors. In the 3GPP EPS network, the
Packet Data Network Gateway (P-GW) and Serving Gateway (S-GW)
constitute another hierarchy of anchors.

3GPP GPRS 3GPP EPS MIP/PMIP
+------+ +------+ +------+
| GGSN | | P-GW | |HA/LMA|
+------+ +------+ +------+
/\ /\ /\
/ \ / \ / \
/ \ / \ / \
/ \ / \ / \
/ \ / \ / \
/ \ / \ / \
/ \ / \ / \
+------+ +------+ +------+ +------+ +------+ +------+
| SGSN | | SGSN | | S-GW | | S-GW | |MN/MAG| |MN/MAG|
+------+ +------+ +------+ +------+ +------+ +------+
/\ /\
/ \ / \
/ \ / \
+---+ +---+ +---+ +---+
|RNC| |RNC| |RNC| |RNC|
+---+ +---+ +---+ +---+

Figure 1. 1: Centralized mobility management. Mobility Management

3.2. Distributed mobility management Mobility Management

Mobility management functions may also be distributed in the data
plane to multiple networks as shown in Figure 2, so that a mobile
node in any of these networks may be served by a nearby function with
appropriate forwarding management (FM) capability.

+------+ +------+ +------+ +------+
| FM | | FM | | FM | | FM |
+------+ +------+ +------+ +------+
|
+----+
| MN |
+----+

Figure 2. 2: Distributed mobility management. Mobility Management

DMM is distributed in the data plane, whereas the control plane may
either
be either centralized or distributed [I-D.yokota-dmm-scenario]. [DMM-SCENARIO]. The former case
implicitly assumes separation of data and control planes as described
in [I-D.wakikawa-netext-pmip-cp-up-separation]. [PMIP-CP-UP-SPLIT]. While mobility management can be distributed,
it is not necessary for other functions such as subscription
management, subscription database, databases, and network access authentication
to be similarly distributed.

A distributed mobility management scheme for a flattening mobile
network consisting of access nodes is proposed in [Paper-
Distributed.Dynamic.Mobility]. [DIST-DYNAMIC-MOB].
Its benefits over centralized mobility management have been shown
through simulations [Paper-
Distributed.Centralized.Mobility]. [DIST-CENTRAL-MOB]. Moreover, the (re)use and
extension of existing protocols in the design of both fully
distributed mobility management [Paper-Migrating.Home.Agents] [Paper-
Distributed.Mobility.SAE] [MIGRATING-HAs] [DIST-MOB-SAE] and
partially distributed mobility management [Paper-Distributed.Mobility.PMIP] [Paper-
Distributed.Mobility.MIP] [DIST-MOB-PMIP]
[DIST-MOB-MIP] have been reported in the literature. Therefore,
before designing new mobility management protocols for a future
distributed architecture, it is recommended to first consider whether
existing mobility management protocols can be extended.

4. Problem Statement

The problems that can be addressed with DMM are summarized in the
following: as
follows:

PS1: Non-optimal routes

Forwarding via a centralized anchor often results in non-
optimal
non-optimal routes, thereby increasing the end-to-end delay.
The problem is manifested, for example, when accessing a nearby
server or servers of a Content Delivery Network (CDN), or when
receiving locally available IP multicast packets or sending IP
multicast packets. (Existing route optimization is only a
host-based solution. On the other hand, localized routing with
PMIPv6 [RFC6705] addresses only a part of the problem where
both the MN and the correspondent node (CN) are attached to the
same MAG, and it is not applicable when the CN does not behave
like an MN.)

PS2: Divergence from other evolutionary trends in network
architectures such as distribution of content delivery. delivery

Mobile networks have generally been evolving towards a flatter
and flatter network. Centralized mobility management, which is
non-optimal with a flatter network architecture, does not
support this evolution.

PS3: Lack of scalability of centralized tunnel management and
mobility context maintenance

Setting up tunnels through a central anchor and maintaining
mobility context for each MN usually requires more concentrated
resources in a centralized design, thus reducing scalability.
Distributing the tunnel maintenance function and the mobility
context maintenance function among different network entities
with proper signaling protocol design can avoid increasing the
concentrated resources with an increasing number of MNs.

PS4: Single point of failure and attack

Centralized anchoring designs may be more vulnerable to a
single
points point of failures failure and attacks than a distributed system.
The impact of a successful attack on a system with centralized
mobility management can be far greater as well.

PS5: Unnecessary mobility support to clients that do not need it

IP mobility support is usually provided to all MNs. Yet However,
it is not always required, and not every parameter of mobility
context is always used. For example, some applications or
nodes do not need a stable IP address during a handover to
maintain session continuity. Sometimes, the entire application
session runs while the MN does not change the point of
attachment. Besides, some sessions, e.g., SIP-based sessions,
can handle mobility at the application layer and hence do not
need IP mobility support; it is then unnecessary to provide IP
mobility support for such sessions.

PS6: Mobility signaling overhead with peer-to-peer communication

Wasting resources

Resources may be wasted when mobility signaling (e.g.,
maintenance of the tunnel, keep alive keep-alive signaling, etc.) is not
turned off for peer-to-peer communication.

PS7: Deployment with multiple mobility solutions

There are already many variants and extensions of MIP as well
as mobility solutions at other layers. Deployment of new
mobility management solutions can be challenging, and debugging
difficult, when they co-exist coexist with solutions already deployed in
the field.

PS8: Duplicate multicast traffic

IP multicast distribution over architectures using IP mobility
solutions (e.g., [RFC6224]) may lead to convergence of
duplicated multicast subscriptions towards the downstream
tunnel entity (e.g., MAG in PMIPv6). Concretely, when
multicast subscription for individual mobile nodes is coupled
with mobility tunnels (e.g., a PMIPv6 tunnel), duplicate
multicast subscription(s) is prone to be received through
different upstream paths. This problem may also exist or be
more severe in a distributed mobility environment.

5. Requirements

After comparing

Now that distributed mobility management against has been compared with
centralized deployment in Section 3 (Section 3) and describing the problems in Section 4, have been
described (Section 4), this section identifies the following
requirements:

REQ1: Distributed mobility management

IP mobility, network access solutions, and forwarding
solutions provided by DMM MUST enable traffic to avoid
traversing a single mobility anchor far from the optimal
route.

This requirement on distribution is in applies to the data plane
only. It does not impose constraints on whether the control
plane should be distributed or centralized. However, if the
control plane is centralized while the data plane is
distributed, it is implicit implied that the control plane and data
plane need to separate (Section 3.2).

Motivation: This requirement is motivated by current trends in
network evolution: (a) it is cost- and resource-effective to
cache contents, and the caching (e.g., CDN) servers are
distributed so that each user in any location can be close to
one of the servers; (b) the significantly larger number of
mobile nodes and flows call for improved scalability; (c)
single points of failure are avoided in a distributed system;
and (d) threats against centrally deployed anchors, e.g., a
home agent and a local mobility anchor, are mitigated in a
distributed system.

This requirement addresses the problems PS1, PS2, PS3, and PS4
described in Section 4.

REQ2: Bypassable network-layer mobility support for each application
session

DMM solutions MUST enable network-layer mobility mobility, but it MUST
be possible for any individual active application session
(flow) to not use it. Mobility support is needed, for
example, when a mobile host moves and an application cannot
cope with a change in the IP address. Mobility support is
also needed when a mobile router changes its IP address as it
moves together with a host and, in the presence of ingress
filtering, an application in the host is interrupted. However
However, mobility support at the network-layer network layer is not always
needed; a mobile node can often be stationary, and mobility
support can also be provided at other layers. It is then not
always necessary to maintain a stable IP address or prefix for
an active application session.

Different active sessions can also differ in whether network-
layer mobility support is needed. IP mobility, network access
solutions, and forwarding solutions provided by DMM MUST then enable
provide the possibility of independent handling for each
application session of a user or mobile device.

The handling of mobility management to the granularity of an
individual session of a user/device SHOULD need proper session
identification in addition to user/device identification.

Motivation: The motivation of this requirement is to enable
more efficient forwarding and more efficient use of network
resources by selecting an IP address or prefix according to
whether mobility support is needed and by not maintaining
context at the mobility anchor when there is no such need.

This requirement addresses the problems PS5 and PS6 described
in Section 4.

REQ3: IPv6 deployment

DMM solutions SHOULD target IPv6 as the primary deployment
environment and SHOULD NOT be tailored specifically to support
IPv4, in particular particularly in situations where private IPv4 addresses
and/or NATs are used.

Motivation: This requirement conforms to the general
orientation of IETF work. DMM deployment is foreseen in as "on
the mid- to long-term horizon, horizon", when IPv6 is expected to be
far more common than today.

This requirement avoids the unnecessarily complexity in
solving complex solution of
trying to provide the problems in Section 4 for IPv4, which will not be
able same level of functionality to use some both IPv4
and IPv6. Some of the IPv6-specific features. features are not
available for IPv4.

REQ4: Existing mobility protocols

A DMM solution MUST first consider reusing and extending IETF-
standardized IETF
standard protocols before specifying new protocols.

Motivation: Reuse of existing IETF work is more efficient and
less error-prone.

This requirement attempts to avoid the need for development of
new protocols
development and therefore their potential problems of for being
time-consuming time-
consuming and error-prone.

REQ5: Coexistence with deployed networks/hosts and operability
across different networks

A DMM solution may require loose, tight tight, or no integration
into existing mobility protocols and host IP stack. stacks.
Regardless of the integration level, DMM implementations MUST
be able to coexist with existing network deployments, end hosts
hosts, and routers that may or may not implement existing
mobility protocols. Furthermore, a DMM solution SHOULD work
across different networks, possibly operated as separate
administrative domains, when the needed mobility management
signaling, forwarding, and network access are allowed by the
trust relationship between them.

Motivation: (a) to (a) preserve backwards compatibility so that
existing networks and hosts are not affected and continue to
function as usual, and (b) enable inter-domain operation if
desired.

This requirement addresses the problem PS7 described in
Section 4.

REQ6: Operation and Management considerations. management considerations

A DMM solution needs to consider configuring a device,
monitoring the current operational state of a device, and
responding to events that impact the device, possibly by
modifying the configuration and storing the data in a format
that can be analyzed later. Different management protocols
are available. For example:

(a) SNMP [RFC1157] the Simple Network Management Protocol (SNMP) [RFC1157],
with definition definitions of standardized management information
base MIB (MIB) objects for DMM, DMM that allows allow the monitoring of
traffic steering in a consistent manner across different devices,
devices

(b) NETCONF [RFC6241] the Network Configuration Protocol (NETCONF) [RFC6241],
with definition definitions of standardized YANG [RFC6020] modules
for DMM to achieve a standardized
configuration, configuration

(c) syslog [RFC3164] [RFC5424], which is a one-way protocol allowing a
device to report significant events to a log analyzer in
a network management system. system

(d) the IP Flow Information Export (IPFIX) Protocol, which
serves as a means for transmitting traffic flow
information over the network [RFC7011], with a formal
description of IPFIX Information Elements [RFC7012]. [RFC7012]

It is not the goal of the this requirements document to impose
which management protocol(s) should be used. An inventory of
the management protocols and data models is covered in RFC
6632.
[RFC6632].

The following lists paragraphs list the operation and management
considerations required for a DMM solution; the this list of
considerations may not be exhaustive and may be expanded
according to the needs of the solutions:

A DMM solution MUST describe how, and in what environment and how types of
environments, it can be scalably deployed and managed.

A DMM solution MUST support mechanisms to test if whether the DMM
solution is working properly. For example, when a DMM
solution employs traffic indirection to support a mobility
session, implementations MUST support mechanisms to test that
the appropriate traffic indirection operations are in place,
including the setup of traffic indirection and the subsequent
teardown of the indirection to release the associated network
resources when the mobility session has closed.

A DMM solution SHOULD expose the operational state of DMM to
the administrators of the DMM entities. For example, when a
DMM solution employs separation between a session identifier
and forwarding address, it should expose the association
between them.

When flow mobility is supported by a DMM solution, the
solution SHOULD support means to correlate the flow routing
policies and the observed forwarding actions.

A DMM solution SHOULD support mechanisms to check the liveness
of a forwarding path. If the DMM solution sends periodic
update refresh messages to configure the forwarding path, the
refresh period SHOULD be configurable and a reasonable default
configuration value proposed. Information collected can be
logged or made available with protocols such as SNMP
[RFC1157], NETCONF [RFC6241], IPFIX [RFC7011], or syslog
[RFC3164].
[RFC5424].

A DMM solution MUST provide fault management and monitoring
mechanisms to manage situations where an update of the
mobility session or the data path fails. The system must also
be able to handle situations where a mobility anchor with
ongoing mobility sessions fails.

A DMM solution SHOULD be able to monitor usage of the DMM
protocol. When a DMM solution uses an existing protocol, the
techniques already defined for that protocol SHOULD be used to
monitor the DMM operation. When these techniques are
inadequate, new techniques MUST be developed.

In particular, the DMM solution SHOULD

(a) be able to monitor the number of mobility sessions per
user
user, as well as their average duration. duration

(b) provide an indication on of DMM performance performance, such as

1 the

(1) handover delay delay, which includes the time necessary to re-establish
reestablish the forwarding path when the point of
attachment changes,

2 the changes
(2) protocol reactivity reactivity, which is the time between
handover events such as the attachment to a new
access point and the completion of the mobility
session
update. update

(d) if tunneling is used for traffic redirection, monitor

(1) the number of tunnels,

2 tunnels

(2) their transmission and reception information,

3 information

(3) the used encapsulation method used, and its overhead

(4) the security used at a the node level. level

DMM solutions SHOULD support standardized configuration with
NETCONF [RFC6241], using YANG [RFC6020] modules, which SHOULD
be created for DMM when needed for such configuration.
However, if a DMM solution creates extensions to MIPv6 or
PMIPv6, the allowed addition of the definition definitions of management
information base (MIB) objects to the MIPv6 MIB [RFC4295] or
the PMIPv6 MIB [RFC6475] that are needed for the control and
monitoring of the protocol extensions SHOULD be limited to
read-only objects.

Motivation: A DMM solution that is designed from the beginning
for operability and manageability can avoid difficulty or
incompatibility to implement efficient
operations and management solutions.

These requirements avoid DMM designs that make operations and
management difficult or costly.

REQ7: Security considerations

A DMM solution MUST support any security protocols and
mechanisms needed to secure the network and to make continuous
security improvements. In addition, with security taken into
consideration early in the design, a DMM solution MUST NOT
introduce new security risks, risks or amplify existing security
risks,
risks that cannot be mitigated by existing security protocols
and mechanisms.

Motivation: Various attacks such as impersonation, denial of
service, man-in-the-middle attacks, and so on, on may be launched
in a DMM deployment. For instance, an illegitimate node may
attempt to access a network providing DMM. Another example is
that a malicious node can forge a number of signaling messages
messages, thus redirecting traffic from its legitimate path.
Consequently, the specific node or nodes to which the traffic
is redirected may be under a denial of service attack, whereas denial-of-service attack and
other nodes do not receive their traffic. Accordingly,
security mechanisms/protocols providing access control,
integrity, authentication, authorization, confidentiality,
etc. should be used to protect the DMM entities as they are
already used to protect against existing networks and existing
mobility protocols defined in the IETF. Yet However, if a
candidate DMM solution is such that even the proper use of these existing security
mechanisms/protocols are unable to provide sufficient security protection,
protection even when properly used, then that candidate DMM
solution is causing uncontrollable security problems.

This requirement prevents a DMM solution from introducing
uncontrollable problems of potentially insecure mobility
management protocols which that make deployment infeasible infeasible, because
platforms conforming to the such protocols are at risk for data
loss and numerous other dangers, including financial harm to
the users.

REQ8: Multicast considerations

DMM SHOULD enable multicast solutions to be developed to avoid
network inefficiency in multicast traffic delivery.

Motivation: Existing multicast deployment deployments have been
introduced after completing the design of the reference
mobility protocol, often leading to network inefficiency and non-
optimal
non-optimal forwarding for the multicast traffic. Instead DMM should
instead consider multicast early in the process, so that the
multicast solutions can better consider efficiency nature in the efficient nature
of multicast traffic delivery (such as duplicate multicast
subscriptions towards the downstream tunnel entities). The
multicast solutions should then avoid restricting the
management of all IP multicast traffic to a single host
through a dedicated (tunnel) interface on multicast-capable
access routers.

This requirement addresses the problems PS1 and PS8 described
in Section 4.

6. Security Considerations

Please refer to the discussion under Security requirement REQ7 in Section 5.

7. IANA Considerations

None

8. Contributors

This requirements document is a joint effort among numerous
participants working in as a team. Valuable comments and suggestions in
various reviews from the following area directors and IESG members
have also contributed to much many improvements: Russ Housley, Catherine
Meadows, Adrian Farrel, Barry Leiba, Alissa Cooper, Ted Lemon, Brian
Haberman, Stephen Farrell, Joel Jaeggli, Alia Atlas, and Benoit
Claise.

In addition to the authors, each of the following has made very
significant and important contributions to the working group
draft in this work:

Charles E. Perkins
Huawei Technologies
Email:
EMail: charliep@computer.org

Melia Telemaco
Alcatel-Lucent Bell Labs
Email:
EMail: telemaco.melia@googlemail.com

Elena Demaria
Telecom Italia
via G. Reiss Romoli, 274, TORINO, Torino, 10148, Italy
Email:
EMail: elena.demaria@telecomitalia.it

Jong-Hyouk Lee
Sangmyung University, Korea
Email:
EMail: jonghyouk@smu.ac.kr

Kostas Pentikousis
EICT GmbH
Email:
EMail: k.pentikousis@eict.de

Tricci So
ZTE
Email:
EMail: tso@zteusa.com

Carlos J. Bernardos
Universidad Carlos III de Madrid
Av. Universidad, 30, Leganes, Madrid 28911, Spain
Email:
EMail: cjbc@it.uc3m.es

Peter McCann
Huawei Technologies
Email:
EMail: Peter.McCann@huawei.com
Seok Joo Koh
Kyungpook National University, Korea
Email:
EMail: sjkoh@knu.ac.kr

Wen Luo
ZTE
No.68,
No. 68, Zijinhua RD,Yuhuatai Rd, Yuhuatai District, Nanjing, Jiangsu 210012,
China
Email:
EMail: luo.wen@zte.com.cn

Sri Gundavelli
Cisco
sgundave@cisco.com

Hui Deng
China Mobile
Email:
EMail: denghui@chinamobile.com

Marco Liebsch
NEC Laboratories Europe
Email:
EMail: liebsch@neclab.eu

Carl Williams
MCSR Labs
Email:
EMail: carlw@mcsr-labs.org

Seil Jeon
Instituto de Telecomunicacoes, Aveiro
Email:
EMail: seiljeon@av.it.pt

Sergio Figueiredo
Universidade de Aveiro
Email:
EMail: sfigueiredo@av.it.pt

Stig Venaas
Email:
EMail: stig@venaas.com

Luis Miguel Contreras Murillo
Telefonica I+D
Email:
EMail: lmcm@tid.es

Juan Carlos Zuniga
InterDigital
Email:
EMail: JuanCarlos.Zuniga@InterDigital.com

Alexandru Petrescu
Email:
EMail: alexandru.petrescu@gmail.com
Georgios Karagiannis
University of Twente
Email:
EMail: g.karagiannis@utwente.nl

Julien Laganier
Juniper
Email:
EMail: julien.ietf@gmail.com

Wassim Michel Haddad
Ericsson
Email:
EMail: Wassim.Haddad@ericsson.com

Dirk von Hugo
Deutsche Telekom Laboratories
Email:
EMail: Dirk.von-Hugo@telekom.de

Ahmad Muhanna
Award Solutions
Email:
EMail: asmuhanna@yahoo.com

Byoung-Jo Kim
ATT Labs
Email:
EMail: macsbug@research.att.com

Hassan Ali-Ahmad
Orange
Email:
EMail: hassan.aliahmad@orange.com

Alper Yegin
Samsung
Email:
EMail: alper.yegin@partner.samsung.com

David Harrington
Effective Software
Email:
EMail: ietfdbh@comcast.net

8. References

9.1.

8.1. Normative References

[RFC1157] Case, J., Fedor, M., Schoffstall, M., and J. Davin,
"Simple Network Management Protocol (SNMP)", STD 15,
RFC 1157, May 1990.

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

[RFC3164] Lonvick, C., "The BSD Syslog Protocol", RFC 3164,
August 2001.

[RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology",
RFC 3753, June 2004.

[RFC4295] Keeni, G., Koide, K., Nagami, K., and S. Gundavelli,
"Mobile IPv6 Management Information Base", RFC 4295,
April 2006.

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

[RFC5424] Gerhards, R., "The Syslog Protocol", RFC 5424, March 2009.

[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010.

[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
Bierman, "Network Configuration Protocol (NETCONF)",
RFC 6241, June 2011.

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

[RFC6475] Keeni, G., Koide, K., Gundavelli, S., and R. Wakikawa,
"Proxy Mobile IPv6 Management Information Base", RFC 6475,
May 2012.

[RFC6632] Ersue, M. and B. Claise, "An Overview of the IETF Network
Management Standards", RFC 6632, June 2012.

[RFC7011] Claise, B., Trammell, B., and P. Aitken, "Specification of
the IP Flow Information Export (IPFIX) Protocol for the
Exchange of Flow Information", STD 77, RFC 7011,
September 2013.

[RFC7012] Claise, B. and B. Trammell, "Information Model for IP Flow
Information Export (IPFIX)", RFC 7012, September 2013.

9.2.

8.2. Informative References

[I-D.bhandari-dhc-class-based-prefix]

[DHCPv6-CLASS-BASED-PREFIX]
Bhandari, S., Halwasia, G., Gundavelli, S., Deng, H.,
Thiebaut, L., Korhonen, J., and I. Farrer, "DHCPv6 class
based prefix", draft-bhandari-dhc-class-based-prefix-05
(work in progress), July 2013.

[I-D.korhonen-6man-prefix-properties]
Korhonen, J., Patil, B., Gundavelli, S., Seite, P., and D.
Liu, "IPv6 Prefix Properties",
draft-korhonen-6man-prefix-properties-02 (work Work in
progress), Progress, July 2013.

[I-D.wakikawa-netext-pmip-cp-up-separation]
Wakikawa, R., Pazhyannur, R., Gundavelli, S., and C.
Perkins, "Separation of Control and User Plane for Proxy
Mobile IPv6",
draft-wakikawa-netext-pmip-cp-up-separation-03 (work in
progress), April 2014.

[I-D.yokota-dmm-scenario]
Yokota, H., Seite, P., Demaria, E., and Z. Cao, "Use case
scenarios for Distributed Mobility Management",
draft-yokota-dmm-scenario-00 (work in progress),
October 2010.

[Paper-Distributed.Centralized.Mobility]

[DIST-CENTRAL-MOB]
Bertin, P., Bonjour, S., and J-M. Bonnin, "A Distributed "Distributed or
Centralized Mobility", Mobility?", Proceedings of Global
Communications the 28th IEEE
Conference on Global Telecommunications (GlobeCom),
December 2009.

[Paper-Distributed.Dynamic.Mobility]

[DIST-DYNAMIC-MOB]
Bertin, P., Bonjour, S., and J-M. Bonnin, "A Distributed
Dynamic Mobility Management Scheme Designed for Flat IP
Architectures", Proceedings of 3rd International
Conference on New Technologies, Mobility and Security
(NTMS), 2008.

[Paper-Distributed.Mobility.MIP]

[DIST-MOB-MIP]
Chan, H., "Distributed Mobility Management with Mobile
IP", Proceedings of IEEE International Communication
Conference (ICC) Workshop on Telecommunications: from
Research to Standards, June 2012.

[Paper-Distributed.Mobility.PMIP]

[DIST-MOB-PMIP]
Chan, H., "Proxy Mobile IP with Distributed Mobility
Anchors", Proceedings of GlobeCom Workshop on Seamless
Wireless Mobility, December 2010.

[Paper-Distributed.Mobility.Review]

[DIST-MOB-REVIEW]
Chan, H., Yokota, H., Xie, J., Seite, P., and D. Liu,
"Distributed and Dynamic Mobility Management in Mobile
Internet: Current Approaches and Issues", Journal of
Communications, vol. 6, no. 1, pp. 4-15, February 2011.

[Paper-Distributed.Mobility.SAE]
Fisher,

[DIST-MOB-SAE]
Fischer, M., Anderson, Andersen, F., Kopsel, A., Schafer, G., and M.
Schlager, "A Distributed IP Mobility Approach for 3G SAE",
Proceedings of the 19th International Symposium on
Personal, Indoor and Mobile Radio Communications (PIMRC),
2008.

[Paper-Locating.User]

[DMM-SCENARIO]
Yokota, H., Seite, P., Demaria, E., and Z. Cao, "Use case
scenarios for Distributed Mobility Management", Work in
Progress, October 2010.

[IPv6-PREFIX-PROPERTIES]
Korhonen, J., Patil, B., Gundavelli, S., Seite, P., and
D. Liu, "IPv6 Prefix Properties", Work in Progress,
July 2013.

[LOCATING-USER]
Kirby, G., "Locating the User", Communication Communications
International, 1995.

[Paper-Migrating.Home.Agents]

[MIGRATING-HAs]
Wakikawa, R., Valadon, G., and J. Murai, "Migrating Home
Agents Towards Internet-scale Mobility Deployments",
Proceedings of the ACM 2nd CoNEXT Conference on Future
Networking Technologies, December 2006.

[Paper-Mobile.Data.Offloading]

[MOB-DATA-OFFLOAD]
Lee, K., Lee, J., Yi, Y., Rhee, I., and S. Chong, "Mobile
Data Offloading: How Much Can WiFi Deliver?", Proceedings
of the ACM SIGCOMM
2010, 2010 Conference, 2010.

[PMIP-CP-UP-SPLIT]
Wakikawa, R., Pazhyannur, R., and S. Gundavelli,
"Separation of Control and User Plane for Proxy Mobile
IPv6", Work in Progress, July 2013.

[RFC5380] Soliman, H., Castelluccia, C., ElMalki, K., and L.
Bellier, "Hierarchical Mobile IPv6 (HMIPv6) Mobility
Management", RFC 5380, October 2008.

[RFC5944] Perkins, C., "IP Mobility Support for IPv4, Revised",
RFC 5944, November 2010.

[RFC6224] Schmidt, T., Waehlisch, M., and S. Krishnan, "Base
Deployment for Multicast Listener Support in Proxy Mobile
IPv6 (PMIPv6) Domains", RFC 6224, April 2011.

[RFC6301] Zhu, Z., Wakikawa, R., and L. Zhang, "A Survey of Mobility
Support in the Internet", RFC 6301, July 2011.

[RFC6705] Krishnan, S., Koodli, R., Loureiro, P., Wu, Q., and A.
Dutta, "Localized Routing for Proxy Mobile IPv6",
RFC 6705, September 2012.

[RFC6909] Gundavelli, S., Zhou, X., Korhonen, J., Feige, G., and R.
Koodli, "IPv4 Traffic Offload Selector Option for Proxy
Mobile IPv6", RFC 6909, April 2013.

[TS.23.401]
3GPP, "General Packet Radio Service (GPRS) enhancements
for Evolved Universal Terrestrial Radio Access Network
(E-UTRAN) access", 3GPP TR TS 23.401 10.10.0, March 2013.

[TS.29303] 12.5.0, June 2014,
<http://www.3gpp.org/ftp/Specs/html-info/23401.htm>.

[TS.29.303]
3GPP, "Domain Name System Procedures; Stage 3", 3GPP
TR 23.303 11.2.0, September 2012.
TS 29.303 12.3.0, June 2014, <http://www.3gpp.org/ftp/
Specs/html-info/29303.htm>.

Authors' Addresses

H. Anthony Chan (editor)
Huawei Technologies
5340 Legacy Dr. Building 3, 3
Plano, TX 75024, 75024
USA
Email:

EMail: h.a.chan@ieee.org

Dapeng Liu
China Mobile
Unit2,
Unit 2, 28 Xuanwumenxi Ave, Xuanwu District, District
Beijing 100053, 100053
China
Email:

EMail: liudapeng@chinamobile.com

Pierrick Seite
Orange
4, rue du Clos Courtel, BP 91226, 91226
Cesson-Sevigne 35512, 35512
France
Email:

EMail: pierrick.seite@orange.com

Hidetoshi Yokota
KDDI Lab
2-1-15 Ohara, Fujimino, Saitama, 356-8502 Japan
Email: yokota@kddilabs.jp
Landis+Gyr

EMail: hidetoshi.yokota@landisgyr.com

Jouni Korhonen
Broadcom Communications
Porkkalankatu 24, 24
Helsinki FIN-00180 Helsinki,
Finland
Email:

EMail: jouni.nospam@gmail.com