Internet DRAFT - draft-ietf-netext-access-network-option
draft-ietf-netext-access-network-option
NETEXT WG S. Gundavelli, Ed.
Internet-Draft Cisco
Intended status: Standards Track J. Korhonen, Ed.
Expires: February 9, 2013 Nokia Siemens Networks
M. Grayson
K. Leung
R. Pazhyannur
Cisco
August 8, 2012
Access Network Identifier (ANI) Option for Proxy Mobile IPv6
draft-ietf-netext-access-network-option-13.txt
Abstract
The local mobility anchor in a Proxy Mobile IPv6 domain is able to
provide access network and access operator specific handling or
policing of the mobile node traffic using information about the
access network to which the mobile node is attached. This
specification defines a mechanism and a related mobility option for
carrying the access network identifier and the access operator
identification information from the mobile access gateway to the
local mobility anchor over Proxy Mobile IPv6.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 9, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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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
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
2.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
3. Access Network Identifier Option . . . . . . . . . . . . . . . 5
3.1. Format of the Access Network Identifier Sub-Option . . . . 6
3.1.1. Network-Identifier Sub-Option . . . . . . . . . . . . 6
3.1.2. Geo-Location Sub-Option . . . . . . . . . . . . . . . 8
3.1.3. Operator-Identifier Sub-Option . . . . . . . . . . . . 9
4. Protocol Considerations . . . . . . . . . . . . . . . . . . . 10
4.1. Mobile Access Gateway Considerations . . . . . . . . . . . 10
4.2. Local Mobility Anchor Considerations . . . . . . . . . . . 12
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
6. Protocol Configuration Variables . . . . . . . . . . . . . . . 14
7. Security Considerations . . . . . . . . . . . . . . . . . . . 16
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 17
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
9.1. Normative References . . . . . . . . . . . . . . . . . . . 17
9.2. Informative References . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
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1. Introduction
Proxy mobile IPv6 [RFC5213] can be used for supporting network-based
mobility management in various type of network deployments. The
network architectures, such as Service provider Wi-Fi access
aggregation or, WLAN integrated mobile packet core are examples where
Proxy Mobile IPv6 is a component of the overall architecture. Some
of these architectures require the ability of the local mobility
anchor (LMA) [RFC5213] to provide differentiated services and
policing of traffic to the mobile nodes based on the access network
to which they are attached. Policy systems in mobility architectures
such as Policy and Charging Control Framework (PCC) [TS23203] and
Access Network Discovery and Selection Function (ANDSF) [TS23402] in
3GPP system allow configuration of policy rules with conditions based
on the access network information. For example, the service
treatment for the mobile node's traffic may be different when they
are attached to a access network owned by the home operator than when
owned by a roaming partner. The service treatment can also be
different based on the configured Service Set Identifiers (SSID) in
case of IEEE 802.11 based access networks. Other examples of
location services include the operator's ability to display a
location specific web page, or apply tariff based on the location.
The Proxy Mobile IPv6 specification [RFC5213] requires the Access
Technology Type (ATT) option to be carried in from the mobile access
gateway (MAG) to the local mobility anchor. This is a mandatory
option. However, the Access Technology Type alone is not necessarily
sufficient for a suitable policy to be applied at the local mobility
anchor. Therefore, there is a need for additional access network
related information to be available at the local mobility anchor.
Learning the access network operator identity may not be possible for
a local mobility anchor without a support of a additional policy
framework that is able to provide required information out of band to
the local mobility anchor. Such a policy framework may not be
required for all Proxy Mobile IPv6 deployments and hence an
alternative approach for optionally carrying such information is
required to ensure that additional information related to the access
network is available.
This document defines a new mobility option, the Access Network
Identifier (ANI) option and its sub-options for Proxy Mobile IPv6,
that can be used by the mobile access gateway to signal the access
network information to the local mobility anchor. The specific
details on how the local mobility anchor uses the information
contained in the Access Network Identifier option are out-of-scope
for this document. This information is intended for use between
infrastructure nodes providing mobile management service and is not
exposed to outside entities, which ensures the location of the
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network to which the mobile node is attached, or any other access
network specific information is not revealed to other mobile nodes
within the PMIPv6 Domain or to other nodes outside the PMIPv6 Domain.
However, the location and access information MAY be exposed to
specific parties outside the PMIPv6 Domain based on an agreement
approved by the subscriber, otherwise, this information MUST NOT be
exposed in the absence of such agreements. This mobility option is
optional and is not mandatory for the Proxy Mobile IPv6 protocol.
However, the Access Technology Type option continues to be a
mandatory option and it always needs to be carried in the Proxy
Mobile IPv6 signaling messages.
SSID: IETF-1
Geo-location: 37o49'11"N 122o28'43"W
Operator-Id: provider1.example.com
+--+
|AP|-------. {Access Specific Policies)
+--+ | _-----_ |
+-----+ _( )_ +-----+
| MAG |-=====( PMIPv6 )======-| LMA |-
+-----+ (_ Tunnel_) +-----+
+--+ | '-----'
|AP|-------'
+--+
SSID: IETF-2
Geo-location: 59o19'40.21"N 18o 3'18.36"E
Operator-Id: provider2.example.com
Figure 1: Access Networks attached to MAG
Figure 1 illustrates an example Proxy Mobile IPv6 deployment where
the mobile access gateway delivers the information elements related
to the access network to the local mobility anchor over Proxy Mobile
IPv6 signaling messages. In this example, the additional information
could comprise the SSID of the used IEEE 802.11 network, the geo-
location of the network to which the mobile node is attached, and the
identities of the operators running the IEEE 802.11 access network
infrastructure.
2. Conventions and Terminology
2.1. Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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2.2. Terminology
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:
Service Set Identifier
Service Set Identifier (SSID) identifies the name of the IEEE
802.11 network. SSID differentiates from one network to the
other.
Operator ID
The Operator ID is the SMI Network Management Private Enterprise
Code of the IANA-maintained Private Enterprise Numbers registry
[SMI] running the network attached to a specific interface of the
mobile access gateway.
3. Access Network Identifier Option
The Access Network Identifier option is a mobility header option used
to exchange access network related information between a local
mobility anchor and a mobile access gateway. The option can be
included in both Proxy Binding Update (PBU) and Proxy Binding
Acknowledgement (PBA) messages, and there MUST NOT be more than a
single instance of this mobility option in a mobility message. The
Access Network Identifier mobility option MUST contain one or more
Access Network Identifier Sub-options. The Access Network Identifier
Sub-option is described in Section 3.1.
The alignment requirement for this option is 4n [RFC2460].
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
... ANI Sub-option(s) ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Access Network Identifier Option
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Type: It MUST be set to value of (IANA-1) (to be defined by IANA),
indicating that its a Network-Identifier option.
Length: 8-bit unsigned integer indicating the length in octets of
the option, excluding the type and length fields.
3.1. Format of the Access Network Identifier Sub-Option
The Access Network Identifier Sub-Options are used for carrying
information elements related to the access network to which the
mobile node is attached to. These sub-options can be included in the
Access Network Identifier option defined in Section 3. The format of
this sub-option is as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ANI Type | ANI Length | Option Data ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Access Network Identifier Sub-Option
ANI Type: 8-bit unsigned integer indicating the type of the Access
Network Identifier sub-option. This specification defines the
following types:
0 - Reserved
1 - Network-Identifier Sub-option
2 - Geo-Location Sub-option
3 - Operator-Identifier Sub-option
ANI Length: 8-bit unsigned integer indicating the number of octets
needed to encode the Option Data, excluding the ANI Type and ANI
Length fields of the sub-option.
3.1.1. Network-Identifier Sub-Option
The Network-Identifier is a mobility sub-option carried in the Access
Network Identifier option defined in Section 3. This sub-option
carries the name of the access network (e.g., a SSID in case of IEEE
802.11 Access Network, or PLMN Identifier [TS23003] in case of 3GPP
access), to which the mobile node is attached. There MUST be no more
than a single instance of this specific sub-option in any Access
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Network Identifier option. The format of this option is defined
below.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ANI Type=1 | ANI Length |E| Reserved | Net-Name Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Network Name (e.g., SSID or PLMNID) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AP-Name Len | Access-Point Name ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Network-Identifier Sub-option
ANI Type: It MUST be set to value of (1), indicating that its a
Network-Identifier sub-option
ANI Length: Total length of this sub option in octets, excluding the
ANI Type and ANI length fields. The value can be in the range of
5 to 32 octets.
'E'-bit: 1-bit flag indicating whether the network name is encoded
in UTF-8. If this flag is set to one (1), then the network name
is encoded using UTF-8 [RFC3629]. If the flag is set to zero (0),
this indicates that the encoding is undefined and is determined by
out-of-band mechanisms. Implementations SHOULD use UTF-8
encoding." "
Reserved: MUST be set to zero when sending and ignored when
received.
Net-Name Length: 8-bit field for representing the length of the
network name in octets to be followed. This field MUST NOT be set
to zero.
Network Name: The name of the access network to which the mobile
node is attached. The type of the network-name is dependent on
the Access Technology to which the mobile node is attached. If
its 802.11 access, the network-name MUST be the SSID of the
network. If the access network is 3GPP access, the network-name
is the PLMN Identifier of the network. If the access network is
3GPP2 access, the network-name is the Access Network Identifier
[ANI].
When encoding the PLMN Identifier, both Mobile Network Code (MNC)
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[TS23003] and Mobile Country Code (MCC) [TS23003] codes MUST be 3
digits. If the MNC in use only has 2 digits, then it MUST be
preceded with a '0'. Encoding MUST be UTF-8.
AP-Name Length: 8-bit field for representing the length of the
access point name in octets to be followed. If the access point
name is not included, then this length MUST be set to a value of
zero.
Access-Point Name: The name of the access point (physical device
name) to which the mobile node is attached. This is the
identifier that uniquely identifies the access point. While
Network Name (Ex: SSID) identifies the operator's access network,
Access-Point Name identifies a specific network-device in that
network to which the mobile node is attached. In some deployments
the Access-Point name can be set to the mac-address of the device,
or some unique identifier that can be used by the policy systems
in the operator network to unambiguously identifies the device.
The string is carried in UTF-8 representation.
3.1.2. Geo-Location Sub-Option
The Geo-Location is a mobility sub-option carried in the Access
Network Identifier option defined in Section 3. This sub-option
carries the Geo-location of the network to which the mobile node is
attached, as known to the mobile access gateway. There MUST be no
more than a single instance of this specific sub-option in any Access
Network Identifier option. The format of this option is defined
below and encodes the co-ordinates of an ellipsoid point. The format
is based on the coordinate reference system used is the World
Geodetic System 1984 [WGS84].
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ANI Type=2 | ANI Length=6 | Latitude Degrees
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Longitude Degrees |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Geo-Location ANI sub-option
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ANI Type: It MUST be set to value of (2), indicating that its Geo-
Location sub-option
ANI Length: Total length of this sub-option in octets, excluding the
ANI Type and ANI length fields. It MUST be set to a value of (6).
Latitude Degrees: A 24-bit latitude degree value encoded as a twos-
complement fixed point number with 9 whole bits. Positive degrees
correspond to the North hemisphere and negative degrees correspond
to the South hemisphere. The degrees range from -90o to +90o.
Longitude Degrees: A 24-bit longitude degree value encoded as a
twos-complement fixed point number with 9 whole bits. The degrees
range from -180o to +180o.
3.1.3. Operator-Identifier Sub-Option
The Operator-Identifier is a mobility sub-option carried in the
Access Network Identifier option defined in Section 3. This sub-
option carries the operator identifier of the access network to which
the mobile node is attached. There MUST be no more than a single
instance of this specific sub-option in any Access Network Identifier
option. The format of this option is defined below.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ANI Type=3 | ANI Length | Op-ID Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Operator Identifier ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: Operator-Identifier Sub-option
ANI Type: It MUST be set to value of (3), indicating that its
Operator-Identifier sub-option
ANI Length: Total length of this sub option in octets, excluding the
ANI Type and ANI length fields.
Operator Identifier (Op-ID) Type: 8-bit unsigned integer indicating
the type of the Operator Identifier. Currently the following
types are defined:
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0 - Reserved.
1 - Operator ID as a variable length Private Enterprise Number
(PEN) [SMI] encoded in a network-byte order. The maximum PEN
value depends on the ANI Length and is calculated using the
formula: maximum PEN = 2^((ANI_length-1)*8)-1. For example,
the ANI Length of 4 allows for encoding PENs from 0 to 2^24-1
i.e. from 0 to 16777215, and uses 3 octets of Operator
Identifier space.
2 - Realm of the operator. Realm names are required to be
unique, and are piggybacked on the administration of the DNS
namespace. Realms meet the syntactic requirements of
requirements of the 'Preferred Name Syntax' defined in Section
2.3.1 of [RFC1035]. They are encoded as US-ASCII.
Operator Identifier: Up to 253 octets of the operator identifier.
The encoding of the identifier depends on the used Operator-ID
Type. For Operator IDs defined in this specification, the
operator identifier MUST NOT be empty.
4. Protocol Considerations
The following considerations apply to the local mobility anchor and
the mobile access gateway.
4.1. Mobile Access Gateway Considerations
o The conceptual Binding Update List entry data structure maintained
by the mobile access gateway, described in Section 6.1 of
[RFC5213], MUST be extended to store the access network related
information elements associated with the current session.
Specifically, the following parameters MUST be defined.
Network-Identifier
Access-Point-Name
Operator-Identifier
Geo-Location
o If the mobile access gateway is configured to support Access
Network Information option, it SHOULD include this option with the
specific sub-options in all Proxy Binding Update messages
(including in Proxy Binding Updates for lifetime extension and for
deregistration) that it sends to the local mobility anchor. The
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Access Network Information option MUST be constructed as specified
in Section 3. It SHOULD include the ANI sub-option(s) that the
mobile access gateway is configured to carry in the Proxy Mobile
IPv6 messages.
o The access network information elements, such as Access-Network
Name, Geo-location and the Operator-Identifier, typically are
statically configured on the mobile access gateway on a per-
interface basis (Example: Access Point (AP-1) is attached through
interface-1, and the SSID is X, Geo-Location is Y). In some
deployments, this information can also be dynamically obtained,
such as through DHCP Option (82), which is the DHCP Relay Agent
Information option [RFC3046]. When the mobile node sends a DHCP
Request, the Access Points typically add the SSID information to
the Option 82 of the DHCP request and when the mobile access
gateway receives this request, it can parse the Option 82 of the
DHCP request and obtain the SSID name. The mobility access
gateway can also obtain this information from the DHCPv6 GeoLoc
Option [RFC6225]. The specific details on how the mobile access
gateway obtains these information elements are access technology
and deployment specific, and is out-side the scope of this
document. It is possible those information elements are
configured on the MAG on a per-interface basis, or dynamically
obtained through some of out-of-band means, such as based on
CAPWAP protocol.
o If the protocol configuration variable,
EnableANISubOptNetworkIdentifier (Section 6), is set to a value of
(1), the mobile access gateway SHOULD include the Network-
Identifier sub-option in the Access Network Identifier option
carried in the Proxy Binding Update. However, if the mobile
access gateway is unable to obtain the network identifier, then it
MUST NOT include this sub-option. For including the Network-
Identifier sub-option, the mobile access gateway needs to be aware
of the network name of the access network (Ex: SSID in case WLAN
Access Network) to which the mobile node is attached. This sub-
option also includes the access-point name for carrying the name
of the access point to which the mobile node is attached. The
access-point name is specially important for applying location
services and given that the network-name (Ex: SSID) may not
provide the needed uniqueness for identifying a location. This
sub-option when included MUST be constructed as described in
Section 3.1.1
o If the protocol configuration variable, EnableANISubOptGeoLocation
(Section 6), is set to a value of (1), the mobile access gateway
SHOULD include the Geo-Location sub-option in the Access Network
Identifier option carried in the Proxy Binding Update. However,
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if the mobile access gateway is unable to obtain the Geo-location,
then it MUST NOT include this sub-option. For including the Geo-
Location sub-option, the mobile access gateway needs to be aware
of the GPS coordinates of the network to which the mobile node is
attached. This sub-option when included MUST be constructed as
described in Section 3.1.2.
o If the protocol configuration variable,
EnableANISubOptOperatorIdentifier (Section 6), is set to a value
of (1), the mobile access gateway SHOULD include the Operator-
Identifier sub-option in the Access Network Identifier option
carried in the Proxy Binding Update. For including the Operator-
Identifier sub-option, the mobile access gateway needs to be aware
of the operator identity of that access network. The access
network operator SHOULD obtain an identifier from the Private
Enterprise Number registry, in order for the mobile access gateway
to carry the operator identifier. If a given access network
operator has not obtained an identifier from the Private
Enterprise Number registry, or if the mobile access gateway is
unable to learn the operator identity for any other administrative
reasons, then it MUST NOT include this sub-option. This sub-
option when included MUST be constructed as described in
Section 3.1.3.
If the mobile access gateway had any of the Access Network
Information mobility option included the Proxy Binding Update sent to
a local mobility anchor, then the Proxy Binding Acknowledgement
received from the local mobility anchor SHOULD contain the Access
Network Information mobility option with the specific sub-options.
If the mobile access gateway receives a Proxy Binding Acknowledgement
with a successful Status Value but without an Access Network
Information mobility option, then the mobile access gateway SHOULD
log the event and based on its local policy MAY proceed to terminate
the mobility session. In this case the mobile access gateway knows
the local mobility anchor does not understand the Access Network
Information mobility option and therefore MAY consider it as a
misconfiguration of the Proxy Mobile IPv6 domain.
4.2. Local Mobility Anchor Considerations
o The conceptual Binding Cache entry data structure maintained by
the local mobility anchor, described in Section 5.1 of [RFC5213],
MUST be extended to store the access network related information
elements associated with the current session. Specifically, the
following parameters MUST be defined.
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Network-Identifier
Access Point Name
Operator-Identifier
Geo-Location
o On receiving a Proxy Binding Update message [RFC5213] from a
mobile access gateway with the Access Network Information option,
the local mobility anchor must process the option and update the
corresponding fields in the Binding Cache entry. If the option is
not understood by that LMA implementation, it will skip the
option.
o If the local mobility anchor understands the Access Network
Identifier mobility option received in a Proxy Binding Update and
also supports the sub-option(s), then the local mobility anchor
MUST echo the Access Network Identifier mobility option with the
specific sub-option(s) that it accepted back to a mobile access
gateway in a Proxy Binding Acknowledgement. The Access Network
Identifier sub-options defined in this specification MUST NOT be
altered by the local mobility anchor.
o If the received Proxy Binding Update message does not include the
Access Network Information option, then the mobility session
associated with that Proxy Binding Update MUST be updated to
remove any access network information elements.
o The local mobility anchor MAY choose to use the access network
information sub-options for applying any access operator specific
handling or policing of the mobile node traffic. The specific
details on how these sub-options are used is outside the scope of
this document.
5. IANA Considerations
This document requires the following IANA actions.
o Action-1: This specification defines a new Mobility Header option,
the Access Network Identifier. This mobility option is described
in Section 3. The Type value for this option needs to be assigned
from the same numbering space as allocated for the other mobility
options, as defined in [RFC6275].
o Action-2: This specification defines a new mobility sub-option
format, Access Network Information (ANI) sub-option. The format
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of this mobility sub-option is described in Section 3.1. This
sub-option can be carried in Access Network Information option.
The type value for this sub-option needs to be managed by IANA,
under the Registry, Access Network Information sub-option. This
specification reserves the following type values. Approval of new
Access Network Information (ANI) sub-option type values are to be
made through IANA Expert Review.
+=========================================================+
| 0 | Reserved |
+=========================================================+
| 1 | Network-Identifier Sub-option |
+=========================================================+
| 2 | Geo-Location Sub-option |
+=========================================================+
| 3 | Operator-Identifier Sub-option |
+=========================================================+
o Action-3: This specification defines a new mobility sub-option,
Operator-Identifier sub-option. The format of this mobility sub-
option is described in Section 3.1.3. The Operator Identifier
(Op-Id) Type field of this sub-option introduces a new number
space. This number space needs to be managed by IANA, under the
Registry, Operator Identifier Type Registry. This specification
reserves the following type values. Approval of new Operator
Identifier Type values are to be made through IANA Expert Review.
+=========================================================+
| 0 | Reserved |
+===+=====================================================+
| 1 | Operator ID as a four octet Private Ent. Number |
+===+=====================================================+
| 2 | Realm of the Operator |
+===+=====================================================+
6. Protocol Configuration Variables
This specification defines the following configuration variables that
control the use of Access Network Information related sub-options in
Proxy Mobile IPv6 signaling messages. The mobility entities, local
mobility anchor and the mobile access gateway MUST allow these
variables to be configured by the system management. The configured
values for these protocol variables MUST survive server reboots and
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service restarts.
EnableANISubOptNetworkIdentifier
This flag indicates the operational state of the Network-
Identifier sub-option support. This configuration variable is
available at both in the mobile access gateway and at the local
mobility anchor. The default value for this flag is set to
(0), indicating that the support for Network-Identifier sub-
option is disabled.
When this flag on the mobile access gateway is set to a value
of (1), the mobile access gateway SHOULD include this sub-
option in the Proxy Binding Update messages that it sends to
the local mobility anchor, otherwise it SHOULD NOT include the
sub-option. There can be situations where the mobile access
gateway is unable to obtain the network-identifier and may not
be able to construct this sub-option.
Similarly, when this flag on the local mobility anchor is set
to a value of (1), the local mobility anchor SHOULD enable
support for this sub-option, otherwise it SHOULD ignore this
sub-option.
EnableANISubOptGeoLocation
This flag indicates the operational state of the Geo-Location
sub-option support. This configuration variable is available
at both in the mobile access gateway and at the local mobility
anchor. The default value for this flag is set to (0),
indicating that the support for Geo-Location sub-option is
disabled.
When this flag on the mobile access gateway is set to a value
of (1), the mobile access gateway SHOULD include this sub-
option in the Proxy Binding Update messages that it sends to
the local mobility anchor, otherwise it SHOULD NOT include the
sub-option. There can be situations where the mobile access
gateway is unable to obtain the geo-location information and
may not be able to construct this sub-option.
Similarly, when this flag on the local mobility anchor is set
to a value of (1), the local mobility anchor SHOULD enable
support for this sub-option, otherwise it SHOULD ignore this
sub-option.
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EnableANISubOptOperatorIdentifier
This flag indicates the operational state of the Operator-
Identifier sub-option support. This configuration variable is
available at both in the mobile access gateway and at the local
mobility anchor. The default value for this flag is set to
(0), indicating that the support for Operator-Identifier sub-
option is disabled.
When this flag on the mobile access gateway is set to a value
of (1), the mobile access gateway SHOULD include this sub-
option in the Proxy Binding Update messages that it sends to
the local mobility anchor, otherwise it SHOULD NOT include the
sub-option. There can be situations where the mobile access
gateway is unable to obtain the operator-identifier information
and may not be able to construct this sub-option.
Similarly, when this flag on the local mobility anchor is set
to a value of (1), the local mobility anchor SHOULD enable
support for this sub-option, otherwise it SHOULD ignore this
sub-option.
7. Security Considerations
The Access Network Information option defined in this specification
is for use in Proxy Binding Update and Proxy Binding Acknowledgement
messages. This option is carried like any other mobility header
option as specified in [RFC6275] and does not require any special
security considerations.
The Geo-location sub-option carried in the Access Network Information
option exposes the geo-location of the network to which the mobile
node is attached. This information is considered to be very
sensitive and so care must be taken to secure the Proxy Mobile IPv6
signaling messages when carrying this sub-option. The base Proxy
Mobile IPv6 specification [RFC5213] specifies the use of IPsec for
securing the signaling messages and those mechanisms can be enabled
for protecting this information. Operators can potentially apply
IPsec ESP with confidentiality and integrity protection for
protecting the location information.
The Access Network specific Information elements that the mobile
access gateway sends may have been dynamically learnt over DHCP, or
using other protocols. If there is no proper security mechanisms in
place, the exchanged information may be potentially compromised with
the mobile access gateway sending incorrect access network parameters
to the local mobility anchor. This situation may potentially result
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in incorrect service policy enforcement at the local mobility anchor
and impact to other services that depend on this access network
information. This threat can be mitigated by ensuring the
communication path between the mobile access gateway and the access
points is properly secured by the use of IPsec, TLS or other security
protocols.
8. Acknowledgements
The authors would like to thank Basavaraj Patil, Carlos Bernardos,
Gerardo Gieratta, Eric Voit, Hidetoshi Yokota, Ryuji Wakikawa,
Sangram Kishore, William Wan, Stefano Faccin and Brian Haberman for
all the discussions related to this topic. The authors would also
like to acknowledge the IESG reviews from Benoit Claise, Stephen
Farrell, Pete Resnick, Robert Spark, Martin Thomson and Ralph Droms.
9. References
9.1. Normative References
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD 63, RFC 3629, November 2003.
[RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.
[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
Mobile IPv6", RFC 5844, May 2010.
[RFC6275] Perkins, C., Johnson, D., and J. Arkko, "Mobility Support
in IPv6", RFC 6275, July 2011.
9.2. Informative References
[ANI] 3GPP2 TSG-A, "Interoperability Specification (IOS) for
High Rate Packet Data (HRPD) Radio Access Network
Interfaces with Session Control in the Access Network",
A.S0008-A v3.0, October 2008.
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
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Internet-Draft Access Network Identifier Option August 2012
(IPv6) Specification", RFC 2460, December 1998.
[RFC3046] Patrick, M., "DHCP Relay Agent Information Option",
RFC 3046, January 2001.
[RFC6225] Polk, J., Linsner, M., Thomson, M., and B. Aboba, "Dynamic
Host Configuration Protocol Options for Coordinate-Based
Location Configuration Information", RFC 6225, July 2011.
[SMI] IANA, "PRIVATE ENTERPRISE NUMBERS", SMI Network Management
Private Enterprise Codes, February 2011.
[TS23003] 3GPP, "Numbering, addressing and identification", 2012.
[TS23203] 3GPP, "Policy and Charging Control Architecture", 2012.
[TS23402] 3GPP, "Architecture enhancements for non-3GPP accesses",
2012.
[WGS84] NIMA, "World Geodetic System 1984, Third Edition, NIMA
TR8350.2, January 2000.", 2010.
Authors' Addresses
Sri Gundavelli (editor)
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
Email: sgundave@cisco.com
Jouni Korhonen (editor)
Nokia Siemens Networks
Linnoitustie 6
Espoo FIN-02600
Finland
Email: jouni.nospam@gmail.com
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Mark Grayson
Cisco
11 New Square Park
Bedfont Lakes, FELTHAM TW14 8HA
ENGLAND
Email: mgrayson@cisco.com
Kent Leung
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
Email: kleung@cisco.com
Rajesh Pazhyannur
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
Email: rpazhyan@cisco.com
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