Internet Engineering Task Force (IETF) F. Xia

Internet Engineering Task Force (IETF) F. Xia
Request for Comments: 6572 B. Sarikaya
Category: Standards Track Huawei USA
ISSN: 2070-1721 J. Korhonen, Ed.
Nokia Siemens Networks
S. Gundavelli
Cisco
D. Damic
Siemens
June 2012

RADIUS Support for Proxy Mobile IPv6

Abstract

This document defines new attributes to facilitate Proxy Mobile IPv6
operations using the RADIUS infrastructure. The protocol defined in
this document uses RADIUS-based interfaces of the mobile access
gateway and the local mobility anchor with the AAA server for
authentication, authorization, and policy functions. The RADIUS
interactions between the mobile access gateway and the RADIUS-based
AAA server take place when the mobile node (MN) attaches,
authenticates, and authorizes to a Proxy Mobile IPv6 domain.
Furthermore, this document defines the RADIUS-based interface between
the local mobility anchor and the AAA RADIUS server for authorizing
received Proxy Binding Update messages for the mobile node's mobility
session. In addition to the interactions related to mobility session
setup, this document defines the baseline for the mobile access
gateway and the local mobility anchor generated accounting.

Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6572.

Xia, et al. Standards Track [Page 1]

RFC 6572 RADIUS PMIPv6 June 2012

Copyright Notice

Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.

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RFC 6572 RADIUS PMIPv6 June 2012

Table of Contents

1. Introduction ....................................................4
2. Terminology .....................................................4
3. Solution Overview ...............................................5
4. Attribute Definitions ...........................................9
4.1. MIP6-Feature-Vector ........................................9
4.2. Mobile-Node-Identifier ....................................11
4.3. Service-Selection .........................................12
4.4. PMIP6-Home-LMA-IPv6-Address ...............................12
4.5. PMIP6-Visited-LMA-IPv6-Address ............................13
4.6. PMIP6-Home-LMA-IPv4-Address ...............................14
4.7. PMIP6-Visited-LMA-IPv4-Address ............................15
4.8. PMIP6-Home-HN-Prefix ......................................15
4.9. PMIP6-Visited-HN-Prefix ...................................16
4.10. PMIP6-Home-Interface-ID ..................................18
4.11. PMIP6-Visited-Interface-ID ...............................18
4.12. PMIP6-Home-IPv4-HoA ......................................19
4.13. PMIP6-Visited-IPv4-HoA ...................................20
4.14. PMIP6-Home-DHCP4-Server-Address ..........................21
4.15. PMIP6-Visited-DHCP4-Server-Address .......................22
4.16. PMIP6-Home-DHCP6-Server-Address ..........................22
4.17. PMIP6-Visited-DHCP6-Server-Address .......................23
4.18. Calling-Station-Id .......................................24
4.19. Chargeable-User-Identity .................................24
4.20. PMIP6-Home-IPv4-Gateway ..................................25
4.21. PMIP6-Visited-IPv4-Gateway ...............................25
5. MAG to RADIUS AAA Interface ....................................26
5.1. Interface Operations ......................................26
5.2. Table of Attributes .......................................27
6. LMA to RADIUS AAA Interface ....................................28
6.1. Interface Operations ......................................28
6.2. Table of Attributes .......................................30
7. Accounting .....................................................31
7.1. Accounting at LMA .........................................31
7.2. Accounting at MAG .........................................32
7.3. Table of Attributes .......................................32
8. Security Considerations ........................................32
9. IANA Consideration .............................................33
9.1. Attribute Type Codes ......................................33
9.2. Namespaces ................................................33
10. Acknowledgements ..............................................34
11. References ....................................................34
11.1. Normative References .....................................34
11.2. Informative References ...................................35

Xia, et al. Standards Track [Page 3]

RFC 6572 RADIUS PMIPv6 June 2012

1. Introduction

Proxy Mobile IPv6 (PMIPv6) [RFC5213] is a network-based mobility
management protocol that allows IP mobility support for a mobile node
without requiring the mobile node's participation in any mobility-
related signaling. The mobile management elements in the network,
the mobile access gateway (MAG) and the local mobility anchor (LMA),
are the two key functions in this network-based mobility system. The
mobile access gateway is responsible for detecting the mobile node's
movements in the network and for initiating the needed mobility
management signaling with the local mobility anchor (LMA). Both the
mobility management agents make use of the AAA infrastructure to
retrieve the mobile node's policy profile and for performing service
authorization.

This document defines a RADIUS-based [RFC2865] profile and
corresponding attributes to be used on the AAA interface between the
MAG and the AAA RADIUS server. This interface is used to carry the
per-MN policy profile from the remote policy store to the MAG.
Furthermore, this document also defines a RADIUS-based interface
between the LMA and the AAA RADIUS server for authorization of the
received Proxy Mobile IPv6 signaling messages. The AAA procedures
defined in this document cover the following two scenarios:

o a mobile node connects to the Proxy Mobile IPv6 domain from the
home network

o a mobile node connects to the Proxy Mobile IPv6 domain from a
visited network

2. Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].

All the mobility-related terms used in this document are to be
interpreted as defined in the Proxy Mobile IPv6 specifications
[RFC5213] and [RFC5844]. Additionally, this document uses the
following abbreviations:

Network Access Server (NAS):

A function that provides authorization services for a device/user
access to the network as defined in [RFC2865]. This document
makes an assumption that the NAS function is co-located with the

Xia, et al. Standards Track [Page 4]

RFC 6572 RADIUS PMIPv6 June 2012

MAG. In scenarios where the NAS function and MAG are decoupled,
the messaging interface needed between them for the operation of
PMIP6 is beyond the scope of this document.

Home AAA (HAAA):

An Authentication, Authorization, and Accounting (AAA) server
located in the MN's home network. This sever has access to the
mobile node's policy profiles.

Visited AAA (VAAA):

An Authentication, Authorization, and Accounting (AAA) server
located in the MN's visited network. The VAAA server takes the
role of a proxy-server, forwarding the received AAA service
request to the HAAA server in the mobile node's home network and
relaying the response to the requesting node, after applying any
local access network policies.

Local AAA (LAAA):

An Authentication, Authorization, and Accounting proxy located in
the local network. In a roaming case, the local AAAA has the
visited AAA role.

3. Solution Overview

This document defines the RADIUS-based AAA interactions with the two
mobility management elements in the Proxy Mobile IPv6 domain.

o Interactions between a MAG and a RADIUS-based AAA server

o Interactions between a LMA and a RADIUS-based AAA server

The mobile node's policy profile [RFC5213] is present in a policy
store and is needed by the PMIPv6 mobility management elements for
authorizing the mobile node for mobility management service and for
obtaining various service-related parameters. This policy store
could be locally co-located with the mobility management agents
enabling direct local access or could be available from a AAA server
through a RADIUS-based AAA interface.

When a mobile node attaches to an access network, the NAS on that
access network may activate the network access authentication
procedure. The choice of the authentication mechanism is specific to
the access network deployment; however, it is typically based on the
Extensible Authentication Protocol (EAP) [RFC3748]. The NAS performs
the network access authentication and queries the HAAA using AAA

Xia, et al. Standards Track [Page 5]

RFC 6572 RADIUS PMIPv6 June 2012

protocol, such as RADIUS. If the network access authentication
succeeds, the MN's policy profile is obtained as part of the RADIUS
message exchange with the AAA server.

The mobile node may be an IPv4-only node, IPv6-only node, or a dual-
stack (IPv4/v6) node. Based on the policy specified in the policy
profile, the network access authentication procedure SHOULD provide
the unambiguous indication of the type of address(es) to be assigned
for the MN in the network and with all other service-related and
policy parameters relevant to the mobility service.

After the successful network access authentication and obtaining the
mobile node's policy profile, the MAG sends a Proxy Binding Update
(PBU) to the LMA. Upon receiving the PBU, the LMA interacts with the
HAAA to obtain the mobile node's policy profile, which is required
for authorizing and activating mobility service.

This document adds support for three distinct PMIPv6 mobility use
cases, taking into account the administrative domains to which the
MAG and the LMA belong. The following are the three relevant
deployment models.

1. the MAG and LMA are both in the home network,

2. the MAG and LMA are both in the visited network,

3. the MAG is in the visited network while the LMA is in the home
network.

Figure 1 shows participating network entities for the PMIPv6 mobility
session, which is located in the home network. The MAG and LMA
interact only with the HAAA.

Xia, et al. Standards Track [Page 6]

RFC 6572 RADIUS PMIPv6 June 2012

+--------+
| HAAA & | RADIUS +-----+
| Policy |<-------->| LMA |
| Profile| +-----+
+--------+ | <--- LMA-Address
^ |
| // \\
+---|------------- //---\\----------------+
( | IPv4/IPv6 // \\ )
( | Network // \\ )
+---|-----------//---------\\-------------+
| // \\
RADIUS // <- Tunnel1 \\ <- Tunnel2
| // \\
| |- MAG1-Address |- MAG2-Address
| +----+ +----+
+---->|MAG1| |MAG2|
+----+ +----+
| |
| |
MN1 MN2

Figure 1: The MAG and LMA Are Both in the Home Network

Figure 2 shows both the LMA and MAG are in the visited network. The
MAG and LMA exchange signaling with the HAAA through the VAAA, which
acts as a Proxy. The visited network may append additional
information to the HAAA replies in order to reflect the local policy.

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RFC 6572 RADIUS PMIPv6 June 2012

+---------------+
| HAAA & |
+----------| Policy Profile|
| +---------------+
|
+---------+
|[VL]AAA &| RADIUS +-----+
| Policy |<------->| LMA |
| Profile | +-----+
+---------+ | <--- LMA-Address
^ // \\
+---|------------- //---\\----------------+
( | IPv4/IPv6 // \\ )
( | Network // \\ )
+---|-----------//---------\\-------------+
| // \\
RADIUS // <- Tunnel1 \\ <- Tunnel2
| // \\
| |- MAG1-Address |- MAG2-Address
| +----+ +----+
+---->|MAG1| |MAG2|
+----+ +----+
| |
MN1 MN2

Figure 2: The MAG and LMA Are Both in the Visited/Local Network

Figure 3 illustrates a topology where the MAG resides in the visited
network while the associated LMA is in MN's home network. Any
message between the MAG and the HAAA passes through the VAAA, which
acts as a Proxy. During the network authentication, the visited
network's specific policy may also be propagated from the VAAA to the
MAG. The LMA has a direct access to the HAAA.

Xia, et al. Standards Track [Page 8]

RFC 6572 RADIUS PMIPv6 June 2012

+---------------+
| HAAA & |
+----------| Policy Profile|
| +---------------+
| |
| RADIUS
+---------+ |
|[VL]AAA &| +-----+
| Policy | | LMA |
| Profile | +-----+
+---------+ | <--- LMA-Address
^ // \\
+---|------------- //---\\----------------+
( | IPv4/IPv6 // \\ )
( | Network // \\ )
+---|-----------//---------\\-------------+
| // \\
RADIUS // <- Tunnel1 \\ <- Tunnel2
| // \\
| |- MAG1-Address |- MAG2-Address
| +----+ +----+
+---->|MAG1| |MAG2|
+----+ +----+
| |
MN1 MN2

Figure 3: Visited MAG and Home LMA Topology

4. Attribute Definitions

4.1. MIP6-Feature-Vector

Diameter [RFC3588] reserves AVP Code space 1-255 as RADIUS attribute
compatibility space. The MIP6-Feature-Vector attribute (Type value
124) defined in [RFC5447] is of type OctetString and contains a
64-bit flags field of supported mobility capabilities. This document
reserves two new capability bits according to the rules in [RFC5447],
and reuses the PMIPv6 capability bits defined by [RFC5779]. The
following capability flag bits are used or defined in this document:

PMIP6_SUPPORTED (0x0000010000000000)

This capability bit is used as defined in [RFC5779].

IP4_HOA_SUPPORTED (0x0000020000000000)

This capability bit is used as defined in [RFC5779]. Assignment
of the IPv4-HoA (Home Address) is defined by [RFC5844].

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RFC 6572 RADIUS PMIPv6 June 2012

LOCAL_MAG_ROUTING_SUPPORTED (0x0000040000000000)

This capability bit is used as defined in [RFC5779].

IP4_TRANSPORT_SUPPORTED (0x0000800000000000)

This capability bit is used for negotiation of the IPv4 transport
support between the MAG and AAA. When the MAG sets this flag bit
in the MIP6-Feature-Vector, it indicates the ability of the MAG to
provide IPv4 transport (i.e., IPv4-based encapsulation) for
carrying IP traffic between the MAG and the LMA. If this flag bit
is unset in the returned MIP6-Feature-Vector attribute, the AAA
does not authorize the use of IPv4 transport on the MAG-to-LMA
tunnel.

IP4_HOA_ONLY_SUPPORTED (0x0001000000000000)

This capability bit is used for determination of the authorized
PMIPv6 mobility mode. When this bit is set by the AAA, it
indicates PMIPv6 mobility with IPv4 support has only been
authorized for the MN. As a result, the RADIUS Access-Accept
SHOULD NOT carry the IPv6 Home Network Prefix (IPv6 HNP). When
this bit is set, the PMIP6_SUPPORTED flag MUST also be set and the
IP4_HOA_SUPPORTED flag MUST NOT be set.

To summarize the use of the MIP6-Feature-Vector the following
capability bit combination settings mean:

PMIP6-SUPPORTED bit set - only IPv6 mobility is supported and
authorized.

PMIP6-SUPPORTED and IP4-ONLY-HOA-SUPPORTED bits set - only IPv4
mobility is supported and authorized.

PMIP6-SUPPORTED and IP4-HOA-SUPPORTED bits set - both IPv6 and
IPv4 mobility are supported and authorized.

The MIP6-Feature-Vector attribute is also used on the LMA to the
RADIUS AAA interface. This capability announcement attribute enables
direct capability negotiation between the LMA and the AAA. The
capabilities that are announced by both parties in the MIP6-Feature-
Vector are known to be mutually supported. The LMA may use this
mechanism during authorization of the received PBU against the AAA to
check individual PMIPv6 feature permissions for a particular MN.

If the RADIUS Access-Accept contains a contradicting combination of
the capability flag bits such as both the IP4_HOA_ONLY_SUPPORTED and
the IP4_HOA_SUPPORTED flags being set, then the RADIUS client MUST

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RFC 6572 RADIUS PMIPv6 June 2012

treat the Access-Accept as an Access-Reject and SHOULD log the event.
Similarly, if the RADIUS Access-Request contains a contradicting
combination of the capability flag bits, then the RADIUS server MUST
reply with an Access-Reject message and SHOULD log the event.

4.2. Mobile-Node-Identifier

The Mobile-Node-Identifier attribute (Type value 145) is of type
String and contains the mobile node identifier (MN-Identifier), see
[RFC5213], in a form of a Network Access Identifier (NAI) [RFC4282].
This identifier and the identifier used for access authentication may
be different; however, there needs to be a mapping between the two
identities as specified in Section 6.6 of [RFC5213]. This attribute
is used on the interface between the MAG and the AAA server. The
Mobile-Node-Identifier attribute is designed for deployments where
the identity used during network access authentication and the
identity used for mobility management is decoupled. It may also be
the case where the MAG does not have means to find out the MN
identity that could be used in subsequent PBU and Proxy Binding
Acknowledgement (PBA) exchanges (e.g., due to identity hiding during
the network access authentication) or when the HAAA wants to assign
periodically changing identities to the MN.

The Mobile-Node-Identifier attribute MAY be returned by the HAAA in
the RADIUS Access-Accept message that completes a successful
authentication and authorization exchange between the MAG and the
HAAA. The MAG MUST use the received MN-Identifier.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Mobile Node Identifier... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
Mobile-Node-Identifier 145.

Length:
In octets, including Type and Length fields (>= 3).

Mobile Node Identifier:
This field is of type String and contains the MN-Identifier
of the MN to be used in the PBU/PBA exchange.

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RFC 6572 RADIUS PMIPv6 June 2012

4.3. Service-Selection

The Service-Selection attribute (Type value 146) is of type UTF-8
text and contains the name of the service or the external network
with which the mobility service for the particular MN SHOULD be
associated [RFC5149]. The identifier MUST be unique within the
PMIPv6 Domain when normalized using the selected normalization form
[UNF] for the particular PMIPv6 Domain deployment. For instance,
[RFC5149] uses the Normalization Form KC (NFKC).

The MAG MUST include the Service-Selection attribute in the Access-
Request sent to the AAA if the information was acquired, e.g., by
operator-specific configuration. The AAA MAY include the Service-
Selection attribute in the Access-Accept response message to the MAG
even if it was not included in the Access-Request as a means of
indicating the MN's default service.

The Service Selection mobility option defined in [RFC5149] can be
used in PBU/PBA messages between the MAG and LMA. On the LMA-to-AAA
interface, the LMA MAY populate the Service-Selection attribute in
the Access-Request message using the service information found in the
received PBU, if such a mobility option were included. The Service-
Selection identifier should be used to assist the PBU authorization,
the assignment of the MN-HNP, and the IPv4-MN-HoA as described in
[RFC5149] and [RFC5779].

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Service Identifier... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
Service-Selection 146.

Length:
In octets, including Type and Length fields (>= 3).

Text:
This field is of type UTF-8 text and contains the Service
Identifier with which the MN is associated.

4.4. PMIP6-Home-LMA-IPv6-Address

The PMIP6-Home-LMA-IPv6-Address attribute (Type value 147) is of type
IPv6 address and is used to deliver the IPv6 address of the LMA
located in the home network.

Xia, et al. Standards Track [Page 12]

RFC 6572 RADIUS PMIPv6 June 2012

Before the MAG can initiate Proxy Mobile IPv6 signaling, it must be
aware of the LMA's IP address.

When the LMA is assigned to the MN from the home network, this
attribute MAY be sent by the HAAA to the MAG in the RADIUS Access-
Accept message.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Home LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home LMA IPv6 address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-LMA-IPv6-Address 147.

Length:
= 18 octets

Home LMA IPv6 address:
128-bit IPv6 address of the assigned home LMA IPv6 address.

4.5. PMIP6-Visited-LMA-IPv6-Address

The PMIP6-Visited-LMA-IPv6-Address attribute (Type value 148) is of
type IPv6 address and is used to propose a particular LMA in the
visited network and to authorize the use of the LMA in the visited/
local network.

PMIP6-Visited-LMA-IPv6-Address attribute MAY be included by the MAG
in the RADIUS Access-Request message. The LMA in the visited/local
network may be assigned by the [VL]AAA as the result of retrieved
policy profile. If included by the [VL]AAA in the RADIUS Access-
Accept sent to the MAG, the use of the LMA in the visited/local
network is authorized and the attribute SHALL carry the IPv6 address
of the LMA assigned for the particular MN. See Section 4.2.5 of
[RFC5447] how the MIP6-Feature-Vector attribute and
LOCAL_HOME_AGENT_ASSIGNMENT capability flag is used with the LMA
(Home Agent) assignment.

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RFC 6572 RADIUS PMIPv6 June 2012

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Visited LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited LMA IPv6 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited LMA IPv6 address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-LMA-IPv6-Address 148.

Length:
= 18 octets

Visited LMA IPv6 address:
128-bit IPv6 address of the assigned visited LMA IPv6 address.

4.6. PMIP6-Home-LMA-IPv4-Address

The PMIP6-Home-LMA-IPv4-Address attribute (Type value 149) is of type
IPv4 address and contains the IPv4 address of the LMA assigned by the
HAAA. The [RFC5844] supports Proxy Mobile IPv6 signaling exchange
between MAG and LMA using the IPv4 transport.

When the LMA is located in the home network, this attribute MAY be
sent by the HAAA to the MAG in the RADIUS Access-Accept message.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Home LMA IPv4 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home LMA IPv4 address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-LMA-IPv4-Address 149.

Length:
= 6 octets

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RFC 6572 RADIUS PMIPv6 June 2012

Home LMA IPv4 address:
32-bit IPv4 address of the assigned LMA.

4.7. PMIP6-Visited-LMA-IPv4-Address

The PMIP6-Visited-LMA-IPv4-Address attribute (Type value 150) is of
type IPv4 address and is used to propose a particular LMA in the
visited network and to authorize the use of the LMA in the visited
network.

PMIP6-Visited-LMA-IPv4-Address attribute MAY be included by the MAG
in the RADIUS Access-Request message. The LMA in the visited/local
network may be assigned by the [VL]AAA as the result of retrieved
policy profile. If included by the [VL]AAA in the RADIUS Access-
Accept sent to the MAG, the use of the LMA in the visited/local
network is authorized and the attribute SHALL carry the IPv4 address
of the LMA assigned for the particular MN. See Section 4.2.5 of
[RFC5447] how the MIP6-Feature-Vector attribute and
LOCAL_HOME_AGENT_ASSIGNMENT capability flag is used with the LMA
(Home Agent) assignment.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Visited LMA IPv4 address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited LMA IPv4 address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-LMA-IPv4-Address 150.

Length:
= 6 octets

IPv4 LMA address:
32-bit IPv4 address of the assigned LMA.

4.8. PMIP6-Home-HN-Prefix

The PMIP6-Home-HN-Prefix attribute (Type value 151) is of type IPv6
prefix. It contains the Mobile Node - Home Network Prefix (MN-HNP),
which is the IPv6 prefix assigned to the link between the MN and the
MAG. The MN configures its IP interface from its home network
prefix(es). When the LMA is located in the home network, the PMIP6-
Home-HN-Prefix attribute is used to deliver the MN-HNP from the HAAA
to the MAG.

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RFC 6572 RADIUS PMIPv6 June 2012

The PMIP6-Home-HN-Prefix attribute is also used on the LMA-to-HAAA
interface containing the prefix assigned to the MN. If the LMA
delegates the MN-HNP assignment to the HAAA, the attribute MUST
contain all zeroes in the address of (i.e., '::') the Access-Request
message. The attribute MUST be present in the RADIUS Access-Accept
message if the prior request already included one and SHOULD carry
the MN-HNP the HAAA assigned to the MN.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved | Prefix-Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Home MN-HNP
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home MN-HNP
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home MN-HNP
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home MN-HNP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-HN-Prefix 151.

Length:
= at least 4 and no larger than 20.

Reserved:
Reserved for future use. The bits MUST be set to zero by the
sender and MUST be ignored by the receiver.

Prefix-Length:
The 8-bit unsigned integer indicating the prefix length of
the home network prefix (at least 0 and no larger than 128).
If the home network prefix contains an address of all zeroes
(i.e., '::'), then the Prefix-Length MUST be set to 128.

Home Network Prefix:
The home network prefix for the MN's IPv6 address configuration.
The Prefix field is up to 16 octets in length. Bits outside of
the Prefix-Length, if included, must be zero.

4.9. PMIP6-Visited-HN-Prefix

The PMIP6-Visited-HN-Prefix attribute (Type value 152) is of type
IPv6 prefix. It contains the Mobile Node - Home Network Prefix (MN-
HNP), which is the IPv6 prefix assigned to the link between the MN

Xia, et al. Standards Track [Page 16]

RFC 6572 RADIUS PMIPv6 June 2012

and the MAG. The MN configures its IP interface from its home
network prefix(es). When the LMA is located in the visited network,
the PMIP6-Visited-HN-Prefix attribute is used to deliver the MN-HNP
from the VAAA to the MAG.

The PMIP6-Visited-HN-Prefix attribute is also used on the LMA-to-VAAA
interface containing the IPv6 prefix assigned to the MN. If the LMA
delegates the assignment of the MN-HNP to the VAAA, the attribute
MUST contain an address of all zeroes (i.e., '::') in the RADIUS
Access-Request message. The attribute MUST be present in Access-
Accept message if the prior request already included one and SHOULD
carry the MN-HNP the VAAA assigned to the MN.

The attribute SHOULD NOT be included if the use of LMA in the home
network is authorized (the PMIP6-Home-HN-Prefix and/or PMIP6-Home-
LMA-IPv6-Address attributes are already present). However, if the
VAAA local policy allows both home and visited LMA addresses to be
delivered to the MAG, then this attribute MAY also be included.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved | Prefix-Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Visited MN-HNP
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited MN-HNP
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited MN-HNP
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited MN-HNP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-HN-Prefix 152.

Length:
= at least 4 and no larger than 20.

Reserved:
Reserved for future use. The bits MUST be set to zero by the
sender and MUST be ignored by the receiver.

Prefix-Length:
The 8-bit unsigned integer indicating the prefix length of
the Visited MN-HNP (at least 0 and no larger than 128). If
the visited home network prefix contains an address of all zeroes
(i.e., '::'), then the Prefix-Length MUST be set to 128.

Xia, et al. Standards Track [Page 17]

RFC 6572 RADIUS PMIPv6 June 2012

Visited Home Network Prefix:
The home network prefix for the MN's IPv6 address configuration.
The Prefix field is up to 16 octets in length. Bits outside of
the Prefix-Length, if included, must be zero.

4.10. PMIP6-Home-Interface-ID

The PMIP6-Home-Interface-ID attribute (Type value 153) is of type
String and contains the MN's interface identifier. The selection of
the interface identifier SHOULD NOT allow the tracking of individual
MNs or users between PMIPv6 mobility sessions for privacy reasons.
This attribute is applicable in network systems and link
technologies, where the network explicitly delivers an interface
identifier to the MN during the link setup. Third Generation
Partnership Project (3GPP) and PPP link technologies are examples of
such.

This attribute MAY be sent by the LMA or the MAG to the HAAA in the
RADIUS Access-Request packet as a proposal. This attribute MAY be
sent by the HAAA to the LMA or to the MAG in an Access-Accept packet;
however, it MUST be present if the prior request already included
one.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Home Interface Identifier
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home Interface Identifier
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home Interface Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-Interface-ID 153.

Length:
= 10 octets.

Home Interface Identifier:
The 64-bit long interface identifier (8 octets).

4.11. PMIP6-Visited-Interface-ID

The PMIP6-Visited-Interface-ID attribute (Type value 154) is of type
String and contains the MN's interface identifier. The selection of
the interface identifier SHOULD NOT allow the tracking of individual
MNs or users between PMIPv6 mobility session for privacy reasons.

Xia, et al. Standards Track [Page 18]

RFC 6572 RADIUS PMIPv6 June 2012

This attribute is applicable in network systems and link
technologies, where the network explicitly delivers an interface
identifier to the MN during the link setup. 3GPP and PPP link
technologies are examples of such.

This attribute MAY be sent by the LMA or the MAG to the VAAA in the
RADIUS Access-Request packet as a proposal. This attribute MAY be
sent by the VAAA to the LMA or to the MAG in an Access-Accept packet;
however, it MUST be present if the prior request already included
one.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Visited Interface Identifier
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited Interface Identifier
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited Interface Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-Interface-ID 154.

Length:
= 10 octets.

Visited Interface Identifier:
The 64-bit long interface identifier (8 octets).

4.12. PMIP6-Home-IPv4-HoA

[RFC5844] specifies extensions to Proxy Mobile IPv6 protocol that
enable IPv4 home address mobility support to the MN. The PMIP6-Home-
IPv4-HoA attribute (Type value 155) is of type Address and contains
the IPv4 Home Address of the MN. The primary use of this attribute
is to deliver the assigned IPv4-HoA from HAAA to the MAG.

The PMIP6-Home-IPv4-HoA is also used on the LMA-to-HAAA interface.
If the LMA in the home network delegates the assignment of the
IPv4-HoA to the HAAA, the attribute MUST contain an address of all
zeroes (i.e., 0.0.0.0) in the Access-Request message. The attribute
MUST be included in by HAAA in the Access-Accept message if the
previous request included it, and it contains the IPv4-HoA assigned
to the MN.

Xia, et al. Standards Track [Page 19]

RFC 6572 RADIUS PMIPv6 June 2012

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved |Prefix-Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Home IPv4 HoA |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-IPv4-HoA 155.

Length:
= 8 octets

Reserved
The 10-bit field reserved for future use. The value MUST be
initialized to zero by sender and MUST be ignored by the
receiver.

Prefix-Len
The 6-bit unsigned integer indicating the prefix length of the
IPv4 HoA. If the Home IPv4 HoA contains an address of all zeroes
(i.e., '0.0.0.0'), then the Prefix-Len MUST be set to 32.

Home IPv4 HoA:
This field is of type Address and contains the IPv4 home
address of the MN in the home network.

4.13. PMIP6-Visited-IPv4-HoA

When both the MAG and the LMA are in the visited network, the PMIP6-
Visited-IPv4-HoA attribute (Type value 156) is of type Address and is
used to exchange information between the VAAA and the MAG on the
assignment of the IPv4 Home Address to the MN being present in the
visited network.

The PMIP6-Visited-IPv4-HoA is also used on the LMA-to-VAAA interface.
If the LMA delegates the assignment of the IPv4-HoA to the VAAA, the
attribute MUST contain an address of all zeroes (i.e., 0.0.0.0) in
the RADIUS Access-Request message. The Access-Accept message MUST
have the attribute present if the prior request to the VAAA already
included one.

The attribute SHOULD NOT be included if the use of the LMA in the
home network is authorized (the PMIP6-Home-IPv4-HoA and/or PMIP6-
Home-LMA-IPv4-Address attributes are already present). However, if
the VAAA local policy allows both home and visited LMA addresses to
be delivered to the MAG, then this attribute MAY also be included.

Xia, et al. Standards Track [Page 20]

RFC 6572 RADIUS PMIPv6 June 2012

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved |Prefix-Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Visited IPv4 HoA |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-IPv4-HoA 156.

Length:
= 8 octets

Reserved:
The 10-bit field reserved for future use. The value MUST be
initialized to zero by the sender and MUST be ignored by the
receiver.

Prefix-Len:
6-bit unsigned integer indicating the prefix length of the IPv4
HoA. If the Visited IPv4 HoA contains an address of all zeroes
(i.e., '0.0.0.0'), then the Prefix-Len MUST be set to 32.

Visited IPv4 HoA:
This field is of type Address and contains the IPv4 home address
of the MN in the visited network.

4.14. PMIP6-Home-DHCP4-Server-Address

The PMIP6-Home-DHCP4-Server-Address (Type value 157) is of type
Address and contains the IPv4 address of the DHCPv4 server in the
home network. The particular DHCP server address is indicated to the
MAG that serves the concerning MN. The HAAA MAY assign a DHCP server
to the MAG in deployments where the MAG acts as a DHCP Relay, as
defined in [RFC5844].

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Home DHCPv4 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home DHCPv4 server address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-DHCP4-Server-Address 157.

Xia, et al. Standards Track [Page 21]

RFC 6572 RADIUS PMIPv6 June 2012

Length:
= 6 octets.

Home DHCPv4 server address:
This field is of type Address and contains a 4-octet IPv4 address
of the DHCP server.

4.15. PMIP6-Visited-DHCP4-Server-Address

The PMIP6-Visited-DHCP4-Server-Address attribute (Type value 158) is
of type Address and delivers the IPv4 address of the DHCPv4 server
from the visited network to the MAG. When both the MAG and the LMA
are in the visited network, the VAAA MAY assign a DHCPv4 server to
the MAG in deployments where the MAG acts as a DHCP Relay, as defined
in [RFC5844].

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Visited DHCPv4 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited DHCPv4 server address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-DHCP4-Server-Address 158.

Length:
= 6 octets

Visited DHCPv4 server address:
This field is of type Address and contains a 4-octet IPv4 address
of the DHCPv4 server.

4.16. PMIP6-Home-DHCP6-Server-Address

The PMIP6-Home-DHCP6-Server-Address (Type value 159) is of type IPv6
address and contains the IPv6 address of the DHCPv6 server in the
home network indicated by the HAAA to the MAG that serves the MN.
The HAAA MAY assign a DHCPv6 server to the MAG in deployments where
the MAG acts as a DHCP Relay, as defined in [RFC5213].

Xia, et al. Standards Track [Page 22]

RFC 6572 RADIUS PMIPv6 June 2012

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Home DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Home DHCPv6 server address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-DHCP6-Server-Address 159.

Length:
= 18 octets

Home DHCPv6 server address:
This field is of type Address and contains 16-octet IPv6 address
of the DHCPv6 server.

4.17. PMIP6-Visited-DHCP6-Server-Address

The PMIP6-Visited-DHCP6-Server-Address attribute (Type value 160) is
of type IPv6 address and contains the IPv6 address of the DHCPv6
server in the visited network indicated by the VAAA to the MAG that
serves the MN. When both MAG and the LMA are located in the visited
network, the VAAA MAY assign a DHCPv6 server to the MAG in
deployments where the MAG acts as a DHCP Relay, as defined in
[RFC5213].

Xia, et al. Standards Track [Page 23]

RFC 6572 RADIUS PMIPv6 June 2012

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Visited DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited DHCPv6 server address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Visited DHCPv6 server address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-DHCP6-Server-Address 160.

Length:
= 18 octets

Visited DHCPv6 server address:
This field is of type Address and contains the 16-octet IPv6
address of the DHCPv6 server.

4.18. Calling-Station-Id

The Calling-Station-Id attribute (Type value 31) is of type String.
When used within PMIPv6 deployments, the attribute contains the MN
Link-Layer Identifier option of the MN as defined in [RFC5213],
Sections 2.2 and 8.6.

4.19. Chargeable-User-Identity

The Chargeable-User-Identity attribute, or CUI, (Type value 89) is a
unique, temporary handle used as means to, for example, correlate
authentication, accounting, and bill post-processing for a particular
chargeable subscriber. The CUI format and use follows guidelines
defined by [RFC4372].

In the scope of this document, the CUI attribute MAY be present in
the Access-Request. The CUI MAY also be present in the Access-
Accept. The CUI MUST be present in the Access-Accept if it was
present in the Access-Request. If the use of the Chargeable-User-
Identity attribute is supported, then the MAG and/or the LMA commits
to include the Chargeable-User-Identity attribute in all subsequent
RADIUS Accounting packets they send for the given user.

Xia, et al. Standards Track [Page 24]

RFC 6572 RADIUS PMIPv6 June 2012

4.20. PMIP6-Home-IPv4-Gateway

[RFC5844] specifies extensions to Proxy Mobile IPv6 protocol that
enable IPv4 home address mobility support to the MN. The PMIP6-Home-
IPv4-Gateway attribute (Type value 161) is of type Address and
contains the default gateway IPv4 address for the MN. This address
is populated into the PMIPv6 IPv4 Default-Router Address Option
[RFC5844]. The address MUST belong to the subnet defined in the
PMIP6-Home-IPv4-HoA attribute.

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Home IPv4 default gateway
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Home-IPv4-Gateway 161.

Length:
= 6 octets

Home IPv4 default gateway address:
This field is of type Address and contains a 4-octet IPv4 default
gateway address.

4.21. PMIP6-Visited-IPv4-Gateway

[RFC5844] specifies extensions to Proxy Mobile IPv6 protocol that
enable IPv4 home address mobility support to the MN. The PMIP6-
Visited-IPv4-Gateway attribute (Type value 162) is of type Address
and contains the default gateway IPv4 address for the MN. This
address is populated into the PMIPv6 IPv4 Default-Router Address
Option [RFC5844]. The address MUST belong to the subnet defined in
the PMIP6-Visited-IPv4-HoA attribute.

Xia, et al. Standards Track [Page 25]

RFC 6572 RADIUS PMIPv6 June 2012

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Visited IPv4 default gateway
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type:
PMIP6-Visited-IPv4-Gateway 162.

Length:
= 6 octets

Visited IPv4 default gateway address:
This field is of type Address and contains a 4-octet IPv4 default
gateway address.

5. MAG to RADIUS AAA Interface

5.1. Interface Operations

The MAG to the AAA RADIUS server interface is used for retrieval of
the policy profile when an MN tries to attach, authenticate, and
authorize to a PMIPv6 domain. Depending on the policies and network
capabilities, the MAG may retrieve different sets of PMIPv6-session-
related parameters:

o Configuration attributes for home or visited network access
scenario, depending on the location and attachment point of the
MN,

o The IPv6 or IPv4 address of the designated LMA, depending on the
access network's actual IP topology,

o The IPv6 or IPv4 configuration parameters for the MN, depending on
the utilized IP configuration method and individual MN's service
Policy,

o The DHCP Relay support attributes (IPv4 or IPv6) in case such
functionality is supported in the network.

In addition to PMIPv6-specific attributes, other RADIUS attributes
are to be used on the MAG-to-AAA interface.

Xia, et al. Standards Track [Page 26]

RFC 6572 RADIUS PMIPv6 June 2012

The User-Name attribute MUST be present in the Access-Request. It
MUST carry a correctly formed identifier that SHOULD correspond to an
MN identity unless the identity is being suppressed for policy
reasons, for example, when identity hiding is in effect. The MN
identity, if available, MUST be in Network Access Identifier (NAI)
[RFC4282] format. At minimum, the home realm of the MN MUST be
available at the MAG when the network access authentication takes
place. Otherwise, the MAG is not able to route RADIUS request
messages towards the correct HAAA. The MN identity used on the MAG-
to-HAAA interface and in the User-Name attribute MAY entirely be
related to the network access authentication and, therefore, not be
suitable to be used as the MN-Identifier mobility option value in the
subsequent PBU/PBA messages. In this case, the HAAA MUST provide the
MN-Identifier for PBU/PBA messages using the Mobile-Node-Identifier
attribute (see Section 4.2).

At least one of the NAS-IP-Address, NAS-IPv6-Address, or
NAS-Identifier attributes MUST be present in the Access-Request. The
Service-Type attribute SHOULD be set to value 1 (Login) and the NAS-
Port-Type attribute SHOULD be present in the Access-Request.

5.2. Table of Attributes

The following table provides a guide to attributes that may be found
in authentication and authorization RADIUS messages between the MAG
and the AAA server.

Xia, et al. Standards Track [Page 27]

RFC 6572 RADIUS PMIPv6 June 2012

Request Accept Reject Challenge # Attribute

1 0-1 0 0 1 User-Name
0-1 0 0 0 4 NAS-IP-Address
0-1 0-1 0 0 5 NAS-Port
0-1 0-1 0 0 6 Service-Type
0-1 0-1 0 0-1 24 State
0 0-1 0 0 25 Class
0 0-1 0 0-1 27 Session-Timeout
0-1 0 0 0 31 Calling-Station-Id
0-1 0 0 0 32 NAS-Identifier
0+ 0+ 0+ 0+ 33 Proxy-State
0-1 0 0 0 69 NAS-Port-Type
0+ 0+ 0+ 0+ 79 EAP-Message
1 1 1 1 80 Message-Authenticator
0-1 0-1 0 0 89 Chargeable-User-Identity
0-1 0 0 0 95 NAS-IPv6-Address
0-1 0-1 0 0 124 MIP6-Feature-Vector
0 1 0 0 145 Mobile-Node-Identifier
0-1 0-1 0 0 146 Service-Selection
0 0-1 0 0 147 PMIP6-Home-LMA-IPv6-Address
0-1 0-1 0 0 148 PMIP6-Visited-LMA-IPv6-Address
0 0-1 0 0 149 PMIP6-Home-LMA-IPv4-Address
0-1 0-1 0 0 150 PMIP6-Visited-LMA-IPv4-Address
0 0+ 0 0 151 PMIP6-Home-HN-Prefix
0 0+ 0 0 152 PMIP6-Visited-HN-Prefix
0 0-1 0 0 153 PMIP6-Home-Interface-ID
0 0-1 0 0 154 PMIP6-Visited-Interface-ID
0 0-1 0 0 155 PMIP6-Home-IPv4-HoA
0 0-1 0 0 156 PMIP6-Visited-IPv4-HoA
0 0-1 0 0 157 PMIP6-Home-DHCP4-Server-Address
0 0-1 0 0 158 PMIP6-Visited-DHCP4-Server-Address
0 0-1 0 0 159 PMIP6-Home-DHCP6-Server-Address
0 0-1 0 0 160 PMIP6-Visited-DHCP6-Server-Address
0 0-1 0 0 161 PMIP6-Home-IPv4-Gateway
0 0-1 0 0 162 PMIP6-Visited-IPv4-Gateway

6. LMA to RADIUS AAA Interface

6.1. Interface Operations

The LMA-to-HAAA interface may be used for multiple purposes. These
include the authorization of the incoming PBU, updating the LMA
address to the HAAA, delegating the assignment of the MN-HNP or the
IPv4-HoA to the HAAA, and accounting and PMIPv6 session management.
The primary purpose of this interface is to update the HAAA with the

Xia, et al. Standards Track [Page 28]

RFC 6572 RADIUS PMIPv6 June 2012

LMA address information in case of dynamically assigned LMA and to
exchange the MN address assignment information between the LMA and
the HAAA.

Whenever the LMA sends an Access-Request message to the HAAA, the
User-Name attribute SHOULD contain the MN's identity. The LMA-
provided identity in the User-Name attribute is strongly RECOMMENDED
to be the same as the MN's identity information in the PBU MN-
Identifier mobility option. The identity SHOULD also be the same as
used on the MAG-to-HAAA interface; however, in case those identities
differ, the HAAA MUST have a mechanism of mapping the MN identity
used on the MAG-to-HAAA interface to the identity used on the LMA-to-
HAAA interface.

If the PBU contains the MN Link-Layer Identifier option, the Calling-
Station-Id attribute SHOULD be included in the request message
containing the received MN Link-Layer Identifier option.
Furthermore, if the PBU contains the Service Selection mobility
option [RFC5149], the Service-Selection attribute SHOULD be included
in the request message containing the received service identifier.
Both the MN Link-Layer Identifier option and the service selection
can be used to provide more information for the PBU authorization
step in the HAAA.

The Service-Type attribute MUST be set to the value 17 (Authorize
Only). If the HAAA is not able to authorize the subscriber's
mobility service session, then the Access-Reject message to the LMA
MAY contain the Reply-Message attribute describing the reason for
rejecting the authorization. A failed authorization obviously
results in a rejection of the PBU, and a PBA with an appropriate
error Status Value MUST be sent back to the MAG.

The authorization step MUST be performed at least for the initial PBU
session up to a mobility session, when the LMA-to-HAAA interface is
deployed. For the subsequent re-registration and handover of PBUs,
the authorization step MAY be repeated (in this case, the LMA-to-HAAA
interface should also maintain an authorization session state).

In case of a dynamic LMA discovery and assignment [RFC6097], the HAAA
and the remote policy store may need to be updated with the selected
LMA address information. The update can be done during the PBU
authorization step using the LMA-to-HAAA interface. This
specification uses the PMIP6-*-LMA-*-Address attribute for carrying
the LMA's address information from the LMA to the HAAA. The LMA
address information in the request message MUST contain the IP
address of the LMA, the Fully Qualified Domain Name (FQDN) uniquely

Xia, et al. Standards Track [Page 29]

RFC 6572 RADIUS PMIPv6 June 2012

identifying the LMA, or both. The LMA address information refers to
the PMIPv6 part of the LMA, not necessarily the LMA part interfacing
with the AAA infrastructure.

The LMA and the HAAA use the PMIP6-Home-HN-Prefix/
PMIP6-Visited-HN-Prefix attributes to exchange the MN-HNP when
appropriate. Similarly, the LMA and the HAAA use the PMIP6-Home-
IPv4-HoA/PMIP6-Visited-IPv4-HoA attributes to exchange the IPv4-MN-
HoA when appropriate. The MN address information exchange is again
done during the PBU authorization step. The HAAA MAY also use the
LMA-provided MN address information as a part of the information used
to authorize the PBU.

Which entity is actually responsible for the address management is
deployment specific within the PMIPv6 Domain and MUST be pre-agreed
on per deployment basis. When the LMA is responsible for the address
management, the PMIP6-*-HN-Prefix/PMIP6-*-IPv4-HoA attributes are
used to inform the HAAA and the remote policy store of the MN-HNP/
IPv4-MN-HoA assigned to the MN. It is also possible that the LMA
delegates the address management to the HAAA. In this case, the
MN-HNP/IPv4-MN-HoA are set to undefined addresses in the Access-
Request message sent from the LMA to the HAAA. The LMA expects to
receive the HAAA assigned HNP/IPv4-MN-HoA in the corresponding
Access-Accept message.

6.2. Table of Attributes

The following table provides a guide to which attributes may be found
in authorization process between LMA and the AAA.

Xia, et al. Standards Track [Page 30]

RFC 6572 RADIUS PMIPv6 June 2012

Request Accept Reject Challenge # Attribute

1 0-1 0 0 1 User-Name
0-1 0-1 0 0 4 NAS-IP-Address
0-1 0-1 0 0 5 NAS-Port
1 0-1 0 0 6 Service-Type
0 0-1 0 0 25 Class
0 0-1 0 0-1 27 Session-Timeout
0-1 0 0 0 31 Calling-Station-Id
1 0 0 0 32 NAS-Identifier
0+ 0+ 0+ 0+ 33 Proxy-State
1 0 0 0 69 NAS-Port-Type
1 1 1 1 80 Message-Authenticator
0-1 0-1 0 0 89 Chargeable-User-Identity
0-1 0-1 0 0 95 NAS-IPv6-Address
0-1 0-1 0 0 124 MIP6-Feature-Vector
1 0 0 0 145 Mobile-Node-Identifier
0-1 0-1 0 0 146 Service-Selection
0-1 0 0 0 147 PMIP6-Home-LMA-IPv6-Address
0-1 0 0 0 148 PMIP6-Visited-LMA-IPv6-Address
0-1 0 0 0 149 PMIP6-Home-LMA-IPv4-Address
0-1 0 0 0 150 PMIP6-Visited-LMA-IPv4-Address
0+ 0+ 0 0 151 PMIP6-Home-HN-Prefix
0+ 0+ 0 0 152 PMIP6-Visited-HN-Prefix
0-1 0-1 0 0 153 PMIP6-Home-Interface-ID
0-1 0-1 0 0 154 PMIP6-Visited-Interface-ID
0-1 0-1 0 0 155 PMIP6-Home-IPv4-HoA
0-1 0-1 0 0 156 PMIP6-Visited-IPv4-HoA
0-1 0-1 0 0 161 PMIP6-Home-IPv4-Gateway
0-1 0-1 0 0 162 PMIP6-Visited-IPv4-Gateway

7. Accounting

Radius-based interfaces at the MAG and LMA with the AAA server
enables the metering of traffic associated with the MN, commonly
called "accounting". If accounting is turned on in the mobile node's
policy profile, the local routing SHOULD NOT be enabled [RFC5213].

7.1. Accounting at LMA

The accounting at the LMA to AAA server interface is based on
[RFC2865] and [RFC2866]. This interface MUST support the transfer of
accounting records needed for service control and charging. These
records should include (but may not be limited to) the following:
time of binding cache entry creation and deletion, number of the
octets sent and received by the MN over the bi-directional tunnel,
etc.

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RFC 6572 RADIUS PMIPv6 June 2012

7.2. Accounting at MAG

The accounting at the MAG to AAA server interface is based on
[RFC2865] and [RFC2866]. The interface MUST also support the
transfer of accounting records that should include the following:
time of binding cache entry creation and deletion, number of the
octets sent and received by the MN over the bi-directional tunnel,
etc.

If there is data traffic between a visiting MN and a correspondent
node that is locally attached to an access link connected to the same
MAG, the mobile access gateway MAY optimize on the delivery efforts
by locally routing the packets instead of using reverse tunneling to
the mobile node's LMA. In this case, the local data traffic too MUST
be reported to AAA Accounting servers by means of RADIUS protocol.

7.3. Table of Attributes

The following table provides a list of attributes that may be
included in the RADIUS Accounting messages. These attributes are to
complement the set of accounting attributes already required by
[RFC2866] and [RFC2869].

Accounting
Request # Attribute

0-1 145 Mobile-Node-Identifier
0-1 146 Service-Selection
0-1 147 PMIP6-Home-LMA-IPv6-Address
0-1 148 PMIP6-Visited-LMA-IPv6-Address
0-1 149 PMIP6-Home-LMA-IPv4-Address
0-1 150 PMIP6-Visited-LMA-IPv4-Address
0+ 151 PMIP6-Home-HN-Prefix
0+ 152 PMIP6-Visited-HN-Prefix
0-1 155 PMIP6-Home-IPv4-HoA
0-1 156 PMIP6-Visited-IPv4-HoA
0-1 31 Calling-Station-Id
0-1 80 Message-Authenticator
0-1 89 Chargeable-User-Identity
0-1 124 MIP6-Feature-Vector

8. Security Considerations

The RADIUS messages may be transported between the MAG and/or the LMA
to the RADIUS server via one or more AAA brokers or RADIUS proxies.
In this case, the communication between the LMA and the RADIUS AAA
server relies on the security properties of the intermediate AAA
brokers and RADIUS proxies.

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RFC 6572 RADIUS PMIPv6 June 2012

Regarding the privacy threats associated with sending MN-specific
information between the MAG and AAA server and between the LMA and
AAA server, considerations of the RADIUS Base protocol [RFC2865],
RADIUS Accounting [RFC2866], and the RADIUS EAP application [RFC3579]
are applicable to this document. The MAG, LMA, and AAA server SHOULD
avoid including attributes containing personally identifying
information such as a MN's Interface ID, link-layer address, or NAI,
except as needed and SHOULD pay special attention if identity hiding
is desired.

9. IANA Consideration

9.1. Attribute Type Codes

This specification defines the following new RADIUS attribute type
values:

Mobile-Node-Identifier 145
Service-Selection 146
PMIP6-Home-LMA-IPv6-Address 147
PMIP6-Visited-LMA-IPv6-Address 148
PMIP6-Home-LMA-IPv4-Address 149
PMIP6-Visited-LMA-IPv4-Address 150
PMIP6-Home-HN-Prefix 151
PMIP6-Visited-HN-Prefix 152
PMIP6-Home-Interface-ID 153
PMIP6-Visited-Interface-ID 154
PMIP6-Home-IPv4-HoA 155
PMIP6-Visited-IPv4-HoA 156
PMIP6-Home-DHCP4-Server-Address 157
PMIP6-Visited-DHCP4-Server-Address 158
PMIP6-Home-DHCP6-Server-Address 159
PMIP6-Visited-DHCP6-Server-Address 160
PMIP6-Home-IPv4-Gateway 161
PMIP6-Visited-IPv4-Gateway 162

9.2. Namespaces

This specification defines new values to the Mobility Capability
registry (see [RFC5447]) for use with the MIP6-Feature-Vector AVP:

Token | Value
----------------------------------+--------------------
IP4_TRANSPORT_SUPPORTED | 0x0000800000000000
IP4_HOA_ONLY_SUPPORTED | 0x0001000000000000

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RFC 6572 RADIUS PMIPv6 June 2012

10. Acknowledgements

First of all, the authors would like to acknowledge the
standardization work and people of the WiMAX Forum that have set the
foundation for this document.

The authors would like to thank Basavaraj Patil, Glen Zorn, Avi Lior,
Alan DeKok, Dhananjay Patki and Pete McCann for reviewing the
document and providing valuable input. The authors also thank Elwyn
Davies, Pete Resnick, Bernard Aboba, Jari Arkko, and Stephen Farrell
for their reviews on the document during the IESG process.

The authors would also like to thank the authors of [RFC5779] as this
document reuses some procedural ideas of that specification.

11. References

11.1. Normative References

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

[RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson,
"Remote Authentication Dial In User Service (RADIUS)",
RFC 2865, June 2000.

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

[RFC4282] Aboba, B., Beadles, M., Arkko, J., and P. Eronen, "The
Network Access Identifier", RFC 4282, December 2005.

[RFC5447] Korhonen, J., Bournelle, J., Tschofenig, H., Perkins, C.,
and K. Chowdhury, "Diameter Mobile IPv6: Support for
Network Access Server to Diameter Server Interaction",
RFC 5447, February 2009.

[RFC3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and J.
Arkko, "Diameter Base Protocol", RFC 3588, September 2003.

[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
Mobile IPv6", RFC 5844, May 2010.

[RFC5779] Korhonen, J., Bournelle, J., Chowdhury, K., Muhanna, A.,
and U. Meyer, "Diameter Proxy Mobile IPv6: Mobile Access
Gateway and Local Mobility Anchor Interaction with
Diameter Server", RFC 5779, February 2010.

Xia, et al. Standards Track [Page 34]

RFC 6572 RADIUS PMIPv6 June 2012

[RFC4372] Adrangi, F., Lior, A., Korhonen, J., and J. Loughney,
"Chargeable User Identity", RFC 4372, January 2006.

11.2. Informative References

[RFC3579] Aboba, B. and P. Calhoun, "RADIUS (Remote Authentication
Dial In User Service) Support For Extensible
Authentication Protocol (EAP)", RFC 3579, September 2003.

[RFC2866] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000.

[RFC2869] Rigney, C., Willats, W., and P. Calhoun, "RADIUS
Extensions", RFC 2869, June 2000.

[RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
Levkowetz, "Extensible Authentication Protocol (EAP)",
RFC 3748, June 2004.

[RFC5149] Korhonen, J., Nilsson, U., and V. Devarapalli, "Service
Selection for Mobile IPv6", RFC 5149, February 2008.

[RFC6097] Korhonen, J. and V. Devarapalli, "Local Mobility Anchor
(LMA) Discovery for Proxy Mobile IPv6", RFC 6097,
February 2011.

[UNF] Davis, M., Ed. and K. Whistler, Ed., "Unicode Standard
Annex #15: Unicode Normalization Forms", January 2012,
<http://www.unicode.org/reports/tr15/>.

Xia, et al. Standards Track [Page 35]

RFC 6572 RADIUS PMIPv6 June 2012

Authors' Addresses

Frank Xia
Huawei USA
1700 Alma Dr., Suite 500
Plano, TX 75075

Phone: +1 972-509-5599
EMail: [email protected]

Behcet Sarikaya
Huawei USA
1700 Alma Dr., Suite 500
Plano, TX 75075

Phone: +1 972-509-5599
EMail: [email protected]

Jouni Korhonen (editor)
Nokia Siemens Networks
Linnoitustie 6
Espoo FI-02600
Finland

EMail: [email protected]

Sri Gundavelli
Cisco
170 West Tasman Drive
San Jose, CA 95134

EMail: [email protected]

Damjan Damic
Siemens
Heinzelova 70a
Zagreb 10000
Croatia

EMail: [email protected]

Xia, et al. Standards Track [Page 36]