| Rfc | 7222 |
|---|
| Title | Quality-of-Service Option for Proxy Mobile IPv6 |
|---|
| Author | M. Liebsch, P.
Seite, H. Yokota, J. Korhonen, S. Gundavelli |
|---|
| Date | May 2014 |
|---|
| Format: | TXT, HTML |
|---|
| Status: | PROPOSED STANDARD |
|---|
|
Internet Engineering Task Force (IETF) M. Liebsch
Request for Comments: 7222 NEC
Category: Standards Track P. Seite
ISSN: 2070-1721 Orange
H. Yokota
KDDI Lab
J. Korhonen
Broadcom Communications
S. Gundavelli
Cisco
May 2014
Quality-of-Service Option for Proxy Mobile IPv6
Abstract
This specification defines a new mobility option, the Quality-of-
Service (QoS) option, for Proxy Mobile IPv6. This option can be used
by the local mobility anchor and the mobile access gateway for
negotiating Quality-of-Service parameters for a mobile node's IP
flows. The negotiated QoS parameters can be used for QoS policing
and marking of packets to enforce QoS differentiation on the path
between the local mobility anchor and the mobile access gateway.
Furthermore, making QoS parameters available on the mobile access
gateway enables mapping of these parameters to QoS rules that are
specific to the access technology and allows those rules to be
enforced on the access network using access-technology-specific
approaches.
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/rfc7222.
Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction ....................................................3
2. Conventions and Terminology .....................................4
2.1. Conventions ................................................4
2.2. Terminology ................................................5
3. Overview of QoS Support in Proxy Mobile IPv6 ....................7
3.1. Quality-of-Service Option -- Usage Examples ................9
3.2. Quality-of-Service Attributes -- Usage Examples ...........11
4. Protocol Messaging Extensions ..................................12
4.1. Quality-of-Service Option .................................12
4.2. Quality-of-Service Attributes .............................14
4.2.1. Per-Mobile-Node Aggregate Maximum Downlink
Bit Rate ...........................................16
4.2.2. Per-Mobile-Node Aggregate Maximum Uplink Bit Rate ..17
4.2.3. Per-Mobility-Session Aggregate Maximum
Downlink Bit Rate ..................................18
4.2.4. Per-Mobility-Session Aggregate Maximum
Uplink Bit Rate ....................................20
4.2.5. Allocation and Retention Priority ..................22
4.2.6. Aggregate Maximum Downlink Bit Rate ................23
4.2.7. Aggregate Maximum Uplink Bit Rate ..................25
4.2.8. Guaranteed Downlink Bit Rate .......................26
4.2.9. Guaranteed Uplink Bit Rate .........................27
4.2.10. QoS Traffic Selector ..............................28
4.2.11. QoS Vendor-Specific Attribute .....................29
4.3. New Status Code for Proxy Binding Acknowledgement .........30
4.4. New Notification Reason for Update Notification Message ...30
4.5. New Status Code for Update Notification
Acknowledgement Message ...................................31
5. Protocol Considerations ........................................31
5.1. Local Mobility Anchor Considerations ......................31
5.2. Mobile Access Gateway Considerations ......................35
6. QoS Services in Integrated WLAN-3GPP Networks ..................39
6.1. Technical Scope and Procedure .............................39
6.2. Relevant QoS Attributes ...................................41
7. IANA Considerations ............................................42
8. Security Considerations ........................................44
9. Acknowledgements ...............................................44
10. References ....................................................44
10.1. Normative References .....................................44
10.2. Informative References ...................................45
Appendix A. Information When Implementing 3GPP QoS in IP
Transport Network ....................................47
A.1. Mapping Tables ............................................47
A.2. Use Cases and Protocol Operations .........................48
A.2.1. Handover of Existing QoS Rules ........................48
A.2.2. Establishment of QoS Rules ............................50
A.2.3. Dynamic Update to QoS Policy ..........................52
Appendix B. Information When Implementing PMIP-Based QoS Support
with IEEE 802.11e ....................................53
Appendix C. Information When Implementing with a Broadband
Network Gateway ......................................57
1. Introduction
Mobile operators deploy Proxy Mobile IPv6 (PMIPv6) [RFC5213] to
enable network-based mobility management for mobile nodes (MNs).
Users can access IP-based services from their mobile device by using
various radio access technologies. The currently supported mobile
standards have adequate support for QoS-based service differentiation
for subscriber traffic in cellular radio access networks. QoS
policies are typically controlled by a policy control function,
whereas the policies are enforced by one or more gateways in the
infrastructure, such as the local mobility anchor (LMA) and the
mobile access gateway (MAG), as well as by access network elements.
Policy control and in-band QoS differentiation for access to the
mobile operator network through alternative non-cellular access
technologies are not supported in the currently specified standards.
Although support for IP session handovers and IP flow mobility across
access technologies already exists in cellular standards [TS23.402],
QoS policy handovers across access technologies has not received much
attention so far.
Based on the deployment trends, Wireless LAN (WLAN) can be considered
as the dominant alternative access technology to complement cellular
radio access. Since the 802.11e extension [IEEE802.11e-2005]
provides QoS extensions to WLAN, it is beneficial to apply QoS
policies to WLAN access, which enables QoS classification of downlink
as well as uplink traffic between a mobile node and its local
mobility anchor. For realizing this capability, this specification
identifies three functional operations:
(a) Maintaining QoS classification during a handover between
cellular radio access and WLAN access by means of establishing QoS
policies in the handover target access network,
(b) mapping of QoS classes and associated policies between
different access systems, and
(c) establishment of QoS policies for new data sessions/flows,
which are initiated while using WLAN access.
This document specifies an extension to the PMIPv6 protocol [RFC5213]
to establish QoS policies for a mobile node's data traffic on the
local mobility anchor and the mobile access gateway. QoS policies
are conveyed in-band with PMIPv6 signaling using the specified QoS
option and are enforced on the local mobility anchor for downlink
traffic and on the mobile access gateway and its access network for
the uplink traffic. The specified option allows association between
IP session classification characteristics, such as a Differentiated
Services Code Point (DSCP) [RFC2474], and the expected QoS class for
the IP session. This document specifies fundamental QoS attributes
that apply on a per-mobile-node, per-mobility-session, or per-flow
basis. The specified attributes are not specific to any access
technology but are compatible with the Third Generation Partnership
Project (3GPP) and IEEE 802.11 Wireless LAN QoS specifications
[IEEE802.11-2012].
Additional QoS attributes can be specified and used with the QoS
option, e.g., to represent more specific descriptions of latency
constraints or jitter bounds. The specification of such additional
QoS attributes as well as the handling of QoS policies between the
mobile access gateway and the access network are out of the scope of
this specification.
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].
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], [RFC5844], and [RFC7077]. Additionally, this document
uses the following abbreviations:
Aggregate Maximum Bit Rate (AMBR)
AMBR defines the upper limit on the bit rate that can be provided
by the network for a set of IP flows. IP packets within the flows
exceeding the AMBR limit may be discarded by the rate-shaping
function where the AMBR parameter is enforced. Variants of the
"AMBR" term can be defined by restricting the target set of IP
flows on which the AMBR is applied to a mobile node, mobility
session, or flow direction. For example, Per-Mobile-Node
Aggregate Maximum Downlink Bit Rate, Per-Mobile-Node Aggregate
Maximum Uplink Bit Rate, Per-Mobility-Session Aggregate Maximum
Downlink Bit Rate, and Per-Mobility-Session Aggregate Maximum
Uplink Bit Rate are used in this document.
Allocation and Retention Priority (AARP)
AARP is used in congestion situations when there are insufficient
resources for meeting all Service Requests. It is used primarily
by the Admission Control function to determine whether a
particular Service Request must be rejected due to lack of
resources or honored by preempting an existing low-priority
service.
Differentiated Services Code Point (DSCP)
In the Differentiated Services Architecture [RFC2474], packets are
classified and marked to receive a particular per-hop forwarding
behavior on nodes along their path based on the marking present on
the packet. This marking on IPv4 and IPv6 packets that defines a
specific per-hop behavior is known as DSCP. Refer to [RFC2474],
[RFC2475], [RFC4594], and [RFC2983] for a complete explanation.
Downlink (DL) Traffic
The mobile node's IP packets that the mobile access gateway
receives from the local mobility anchor are referred to as the
Downlink traffic. The "Downlink" term used in the QoS attribute
definition is always from the reference point of the mobile node,
and it implies traffic heading towards the mobile node.
Guaranteed Bit Rate (GBR)
GBR denotes the assured bit rate that will be provided by the
network for a set of IP flows. It is assumed that the network
reserves the resources for supporting the GBR parameter. Variants
of the "GBR" term can be defined by limiting the scope of the
target IP flows on which the GBR is applied to a mobile node,
mobility session, or flow direction. For example, Guaranteed
Downlink Bit Rate and Guaranteed Uplink Bit Rate are used in this
document.
Mobility Session
The term "mobility session" is defined in [RFC5213]. It refers to
the creation or existence of state associated with the mobile
node's mobility binding on the local mobility anchor and on the
mobile access gateway.
QoS Service Request
A QoS Service Request is a set of QoS parameters that are defined
to be enforced on one or more mobile node's IP flows. The
parameters at the minimum include a DSCP marking and additionally
may include Guaranteed Bit Rate or Aggregate Maximum Bit Rate.
The Quality-of-Service option defined in this document represents
a QoS Service Request.
Service Identifier
In some mobility architectures, multiple services within the same
mobility service subscription are offered to a mobile node. Each
of those services provide a specific service (for example,
Internet Service and Voice Over IP Service) and has an identifier
called "Service Identifier". 3GPP APN (Access Point Name) is an
example of a Service Identifier. Refer to [RFC5149] for the
definition of the Service Identifier and the mobility option used
for carrying the Service Identifier.
Uplink (UL) Traffic
The mobile node's IP packets that the mobile access gateway
forwards to the local mobility anchor are referred to as the
Uplink traffic. The "Uplink" term used in the QoS attribute
definitions is based on the reference point of the mobile node,
and it implies traffic originating from the mobile node.
3. Overview of QoS Support in Proxy Mobile IPv6
The Quality-of-Service support in Proxy Mobile IPv6 specified in this
document is based on the Differentiated Services Architecture
([RFC2474] and [RFC2475]). The access and the home network in the
Proxy Mobile IPv6 domain are assumed to be DiffServ-enabled, with
every network node in the forwarding path for the mobile node's IP
traffic being DiffServ-compliant. The per-hop behavior for providing
differential treatment based on the DiffServ marking in the packet is
assumed to be supported in the Proxy Mobile IPv6 domain.
The local mobility anchor in the home network and the mobile access
gateway in the access network define the network boundary between the
access and the home network. As the tunnel entry and exit points for
the mobile node's IP traffic, these entities are the logical choice
for being chosen as the QoS enforcement points. The basic QoS
functions such as marking, metering, policing, and rate-shaping on
the mobile node's IP flows can be enforced at these nodes.
The local mobility anchor and the mobile access gateway can negotiate
the Quality-of-Service parameters for a mobile node's IP flows based
on the signaling extensions defined in this document. The QoS
services that can be enabled for a mobile node are for meeting both
the quantitative performance requirements (such as Guaranteed Bit
Rate) as well as for realizing relative performance treatment by way
of class-based differentiation. The subscriber's policy and the
charging profile (for example, [TS22.115]) are key considerations for
the mobility entities in the QoS service negotiation. The decision
on the type of QoS services that are to be enabled for a mobile node
is based on the subscriber profile and based on available network
resources. The negotiated QoS parameters are used for providing QoS
differentiation on the path between the local mobility anchor and the
mobile access gateway. The signaling related to QoS services is
strictly between the mobility entities and does not result in per-
flow state or signaling to any other node in the network.
+=======+
| MN-1 |
+=======+
| | | Flow-6
Flow-1<--(GBR: 64 Kbps) |
| Flow-4 |
Flow-2 | | |
| | Flow-1 | |
| Flow-3 | | |
|_|_| DSCP-X | | |
( )<--(Per-Session-AMBR: 1 Mbps) : | | |
| | | DSCP-Z : | | |
| | : : | | |
| | | +=====+ +==:=v+ | | |
| '- -- - - - --| | | : o|--' | |
| '- - --- - - -| | __ | v o|----' |
'- - - - - - - -| | _--' '--_ | o--|------'
| | ( ) | |
| MAG |=====( IP Network )=====| LMA |
| | ( ) | |
,- - - - - - - - -| | '--__--' | o|-- - -,
,- - -- - -- - -| | | o|--- , |
| | ,- - - - -- -| | | o|--, | |
| | +=====+ +====^+ | | |
|_|_| : | | |
( _ _ )<--(Per-Session-AMBR: 2 Mbps) : | | |
| | | DSCP-Y | | |
| | | | |
| | | | | |
| Flow-6 Flow-2 | |
| | | |
Flow-5 (MBR: 100 Kbps) Flow-3 |
| |
Flow-4 (GBR: 64 Kbps) Flow-5
| | |
+=======+
| MN-2 |
+=======+
Figure 1: QoS Support
Figure 1 illustrates the support of QoS services in a Proxy Mobile
IPv6 domain. The local mobility anchor and the mobile access gateway
have negotiated QoS parameters for the mobility sessions belonging to
MN-1 and MN-2. The negotiated QoS parameters include a Per-Session-
AMBR of 1 Mbps and 2 Mbps for MN-1 and MN-2 respectively.
Furthermore, different IP flows from MN-1 and MN-2 are given
different QoS service treatment, for example, a GBR of 64 Kbps for
Flow-1 and Flow-4 is assured, a DSCP marking enforcement of "Z" on
Flow-6, and an MBR of 100 Kbps on Flow-5.
3.1. Quality-of-Service Option -- Usage Examples
Use Case 1: Figure 2 illustrates a scenario where a local mobility
anchor initiates a QoS Service Request to a mobile access gateway.
+-----+ +-----+ +-----+
| MN | | MAG | | LMA |
+-----+ +-----+ +-----+
| | |
1) |---- MN Attach ----| |
2) | |------ PBU ------->|
3) | |<----- PBA --------|
| | |
4) | |o=================o|
| | PMIPv6 Tunnel |
| | |
| (LMA initiates QoS Service Request) |
5) | |<----- UPN (QoS)---|
| | |
| (MAG proposes a revised QoS Request) |
6) | |------ UPA (QoS')->|
| | |
7) | |<----- UPN (QoS')--|
8) | |------ UPA (QoS')->|
| QoS Rules ---| |
9) | Established <-| | QoS Rules ---|
10) | ---| Established <-| |
| | ---|
11) |<----------------->| |
Figure 2: LMA-Initiated QoS Service Request
o (1) to (4): MAG detects the mobile node's attachment to the access
link and initiates the signaling with the local mobility anchor.
Upon completing the signaling, the LMA and MAG establish the
mobility session and the forwarding state.
o (5) to (8): The LMA initiates a QoS Service Request to the mobile
access gateway. The trigger for this service can be based on a
trigger from a policy function, and the specific details of that
trigger are outside the scope of this document. The LMA sends an
Update Notification (UPN) message [RFC7077] to the MAG. The
message includes the QoS option (Section 4.1), which includes a
set of QoS parameters. On determining that it cannot support the
requested QoS Service Request for that mobile, the MAG sends an
Update Notification Acknowledgement (UPA) message. The message
contains a revised QoS option with an updated set of QoS
attributes. The LMA accepts the revised QoS Service Request by
sending a new Update Notification message including the updated
QoS option.
o (9) to (11): Upon successfully negotiating a QoS Service Request,
the MAG and the LMA install the QoS rules for that Service
Request. Furthermore, the MAG (using access-technology-specific
mechanisms) installs the QoS rules on the access network.
Use Case 2: Figure 3 illustrates a scenario where a mobile access
gateway initiates a QoS Service Request to a local mobility anchor.
+-----+ +-----+ +-----+
| MN | | MAG | | LMA |
+-----+ +-----+ +-----+
| | |
1) |---- MN Attach ----| |
2) | |------ PBU ------->|
3) | |<----- PBA --------|
| | |
4) | |o=================o|
| | PMIPv6 Tunnel |
| | |
| (MAG initiates QoS Service Request) |
5) | |------ PBU (QoS)-->|
6) | |<----- PBA (QoS)---|
| QoS Rules ---| |
7) | Established <-| | QoS Rules ---|
8) | ---| Established <-| |
| | ---|
9) |<----------------->| |
Figure 3: MAG-Initiated QoS Service Request
o (1) to (4): MAG detects the mobile node's attachment to the access
link and initiates the signaling with the local mobility anchor.
Upon completing the signaling, the LMA and MAG establish the
mobility session and the forwarding state.
o (5) to (6): The MAG initiates a QoS Service Request to the local
mobility anchor. The trigger for this service can be based on a
trigger from the mobile node using access-technology-specific
mechanisms. The specific details of that trigger are outside the
scope of this document. The MAG sends a Proxy Binding Update
(PBU) message [RFC5213] to the LMA. The message includes the QoS
option (Section 4.1), which includes a set of QoS parameters. The
LMA agrees to the proposed QoS Service Request by sending a Proxy
Binding Acknowledgement (PBA) message.
o (7) to (9): Upon successfully negotiating a QoS Service Request,
the MAG and the LMA install the QoS rules for that Service
Request. Furthermore, the MAG using access-technology-specific
mechanisms installs the QoS rules on the access network.
3.2. Quality-of-Service Attributes -- Usage Examples
This section identifies the use cases where the Quality-of-Service
option (Section 4.1) and its attributes (Section 4.2) defined in this
document are relevant.
o The subscription policy offered to a mobile subscriber requires
the service provider to enforce Aggregate Maximum Bit Rate (AMBR)
limits on the subscriber's IP traffic. The local mobility anchor
and the mobile access gateway negotiate the uplink and the
downlink AMBR values for the mobility session and enforce them in
the access and the home network. The QoS option (Section 4.1)
with the QoS attributes Per-Session-Agg-Max-DL-Bit-Rate
(Section 4.2.3) and Per-Session-Agg-Max-UL-Bit-Rate
(Section 4.2.4) is used for this purpose.
o In Community Wi-Fi deployments, the residential gateway
participating in the Wi-Fi service is shared between the home user
and the community Wi-Fi users. In order to ensure the home user's
Wi-Fi service is not impacted because of the community Wi-Fi
service, the service provider enables Guaranteed Bit Rate (GBR)
for the home user's traffic. The QoS option (Section 4.1) with
the QoS attributes Guaranteed-DL-Bit-Rate (Section 4.2.8) and
Guaranteed-UL-Bit-Rate (Section 4.2.9) is used for this purpose.
o A mobile user using the service provider's Voice over IP
infrastructure establishes a VoIP call with some other user in the
network. The negotiated call parameters for the VoIP call require
a dedicated bandwidth of certain fixed value for the media flows
associated with that VoIP session. The application function in
the VoIP infrastructure notifies the local mobility anchor to
enforce the GBR limits on that IP flow identified by the flow
definition. The QoS option (Section 4.1) with the QoS attributes
Guaranteed-DL-Bit-Rate (Section 4.2.8), Guaranteed-UL-Bit-Rate
(Section 4.2.9), and QoS-Traffic-Selector (Section 4.2.10) is used
for this purpose.
o An emergency service may require network resources in conditions
when the network resources have been fully allocated to other
users and the network may be experiencing severe congestion. In
such cases, the service provider may want to revoke resources that
have been allocated and reassign them to emergency services. The
local mobility anchor and the mobile access gateway negotiate
Allocation and Retention Priority (AARP) values for the IP
sessions associated with the emergency applications. The QoS
option (Section 4.1) with the QoS attribute Allocation-Retention-
Priority (Section 4.2.5) is used for this purpose.
4. Protocol Messaging Extensions
4.1. Quality-of-Service Option
The Quality-of-Service option is a mobility header option used by
local mobility anchors and mobile access gateways for negotiating QoS
parameters associated with a mobility session. This option can be
carried in Proxy Binding Update (PBU) [RFC5213], Proxy Binding
Acknowledgement (PBA) [RFC5213], Update Notification (UPN) [RFC7077]
and Update Notification Acknowledgement (UPA) [RFC7077] messages.
There can be more than one instance of the Quality-of-Service option
in a single message. Each instance of the Quality-of-Service option
represents a specific QoS Service Request.
The alignment requirement for this option is 4n.
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 | SR-ID | TC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OC | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ QoS Attribute(s) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: QoS Option
o Type: 58
o Length: 8-bit unsigned integer indicating the length of the option
in octets, excluding the Type and Length fields.
o Service Request Identifier (SR-ID): An 8-bit unsigned integer used
for identifying the QoS Service Request. Its uniqueness is within
the scope of a mobility session. The local mobility anchor always
allocates the Service Request Identifier. When a new QoS Service
Request is initiated by a mobile access gateway, the Service
Request Identifier in the initial request message is set to a
value of (0), and the local mobility anchor allocates a Service
Request Identifier and includes it in the response. For any new
QoS Service Requests initiated by a local mobility anchor, the
Service Request Identifier is set to the allocated value.
o Traffic Class (TC): Traffic Class consists of a 6-bit DSCP field
followed by a 2-bit reserved field.
Differentiated Services Code Point (DSCP)
A 6-bit unsigned integer indicating the code point value, as
defined in [RFC2475] to be used for the mobile node's IP flows.
When this DSCP marking needs to be applied only for a subset of
a mobile node's IP flows, there will be a Traffic Selector
attribute (Section 4.2.10) in the option, which provides the
flow selectors. In the absence of any such Traffic Selector
attribute, the DSCP marking applies to all the IP flows
associated with the mobility session.
Reserved
The last two bits in the Traffic Class field are currently
unused. These bits MUST be initialized by the sender to (0)
and MUST be ignored by the receiver.
o Operational Code (OC): 1-octet Operational code indicates the type
of QoS request.
RESPONSE: (0)
Response to a QoS request
ALLOCATE: (1)
Request to allocate QoS resources
DE-ALLOCATE: (2)
Request to de-Allocate QoS resources
MODIFY: (3)
Request to modify QoS parameters for a previously negotiated
QoS Service Request
QUERY: (4)
Query to list the previously negotiated QoS Service Requests
that are still active
NEGOTIATE: (5)
Response to a QoS Service Request with a counter QoS proposal
Reserved: (6) to (255)
Currently not used. Receiver MUST ignore the option received
with any value in this range.
o Reserved: This field is unused for now. The value MUST be
initialized to a value of (0) by the sender and MUST be ignored by
the receiver.
o QoS Attribute(s): Zero or more TLV-encoded QoS attributes. The
format of the QoS attribute is defined in Section 4.2. The
interpretation and usage of the QoS attribute is based on the
value in the Type field.
4.2. Quality-of-Service Attributes
This section identifies the format of a Quality-of-Service attribute.
A QoS attribute can be included in the Quality-of-Service option
defined in Section 4.1. This section identifies the QoS attributes
defined by this specification.
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 | Value ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Format of a Quality-of-Service Attribute
o Type: 8-bit unsigned integer indicating the type of the QoS
attribute. This specification reserves the following values.
(0) - Reserved
This value is reserved and cannot be used
(1) - Per-MN-Agg-Max-DL-Bit-Rate
This QoS attribute, Per-Mobile-Node Aggregate Maximum Downlink
Bit Rate, is defined in Section 4.2.1.
(2) - Per-MN-Agg-Max-UL-Bit-Rate
This QoS attribute, Per-Mobile-Node Aggregate Maximum Uplink
Bit Rate, is defined in Section 4.2.2.
(3) - Per-Session-Agg-Max-DL-Bit-Rate
This QoS attribute, Per-Mobility-Session Aggregate Maximum
Downlink Bit Rate, is defined in Section 4.2.3.
(4) - Per-Session-Agg-Max-UL-Bit-Rate
This QoS attribute, Per-Mobility-Session Aggregate Maximum
Uplink Bit Rate, is defined in Section 4.2.4.
(5) - Allocation-Retention-Priority
This QoS attribute, Allocation and Retention Priority, is
defined in Section 4.2.5.
(6) - Aggregate-Max-DL-Bit-Rate
This QoS attribute, Aggregate Maximum Downlink Bit Rate, is
defined in Section 4.2.6.
(7) - Aggregate-Max-UL-Bit-Rate
This QoS attribute, Aggregate Maximum Uplink Bit Rate, is
defined in Section 4.2.7.
(8) - Guaranteed-DL-Bit-Rate
This QoS attribute, Guaranteed Downlink Bit Rate, is defined in
Section 4.2.8.
(9) - Guaranteed-UL-Bit-Rate
This QoS attribute, Guaranteed Uplink Bit Rate, is defined in
Section 4.2.9.
(10) - QoS-Traffic-Selector
This QoS attribute, QoS Traffic Selector, is defined in
Section 4.2.10.
(11) - QoS-Vendor-Specific-Attribute
This QoS attribute, QoS Vendor-Specific Attribute, is defined
in Section 4.2.11.
(12) to (254) - Reserved
These values are reserved for future allocation.
(255) - Reserved
This value is reserved and cannot be used.
o Length: 8-bit unsigned integer indicating the number of octets
needed to encode the Value, excluding the Type and Length fields.
o Value: The format of this field is based on the Type value.
4.2.1. Per-Mobile-Node Aggregate Maximum Downlink Bit Rate
This attribute, Per-MN-Agg-Max-DL-Bit-Rate, represents the maximum
downlink bit rate for a mobile node. It is a variant of the "AMBR"
term defined in Section 2.2. This value is an aggregate across all
mobility sessions associated with that mobile node.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by a
local mobility anchor, it indicates the maximum aggregate downlink
bit rate that is being requested for the mobile node at the peer.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the maximum aggregate downlink bit rate that the peer
agrees to offer.
If multiple mobility sessions are established for a mobile node,
through multiple mobile access gateways with sessions anchored either
on a single local mobility anchor or spread out across multiple local
mobility anchors, then it depends on the operator's policy and the
specific deployment as to how the total bandwidth for the mobile node
on each MAG-LMA pair is computed.
When a QoS option includes both the Per-MN-Agg-Max-DL-Bit-Rate
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the QoS-Traffic-Selector attribute does not apply to this
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 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Per-MN-Agg-Max-DL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 1
o Length: The length in octets of the attribute, excluding the Type
and Length fields. This value is set to (6).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Per-MN-Agg-Max-DL-Bit-Rate: This is a 32-bit unsigned integer that
indicates the aggregate maximum downlink bit rate that is
requested/allocated for all the mobile node's IP flows. The
measurement units for Per-MN-Agg-Max-DL-Bit-Rate are bits per
second.
4.2.2. Per-Mobile-Node Aggregate Maximum Uplink Bit Rate
This attribute, Per-MN-Agg-Max-UL-Bit-Rate, represents the maximum
uplink bit rate for the mobile node. It is a variant of the "AMBR"
term defined in Section 2.2. This value is an aggregate across all
mobility sessions associated with that mobile node.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by
the local mobility anchor, it indicates the maximum aggregate uplink
bit rate that is being requested for the mobile node at the peer.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the maximum aggregate uplink bit rate that the peer agrees
to offer for that mobile node.
If multiple mobility sessions are established for a mobile node,
through multiple mobile access gateways with sessions anchored either
on a single local mobility anchor or spread out across multiple local
mobility anchors, then it depends on the operator's policy and the
specific deployment as to how the total bandwidth for the mobile node
on each MAG-LMA pair is computed.
When a QoS option includes both the Per-MN-Agg-Max-UL-Bit-Rate
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the QoS-Traffic-Selector attribute does not apply to this
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 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Per-MN-Agg-Max-UL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 2
o Length: The length in octets of the attribute, excluding the Type
and Length fields. This value is set to (6).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Per-MN-Agg-Max-UL-Bit-Rate: This is a 32-bit unsigned integer that
indicates the aggregate maximum uplink bit rate that is requested/
allocated for the mobile node's IP flows. The measurement units
for Per-MN-Agg-Max-UL-Bit-Rate are bits per second.
4.2.3. Per-Mobility-Session Aggregate Maximum Downlink Bit Rate
This attribute, Per-Session-Agg-Max-DL-Bit-Rate, represents the
maximum downlink bit rate for the mobility session. It is a variant
of the "AMBR" term defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by
the local mobility anchor, it indicates the maximum aggregate
downlink bit rate that is being requested for that mobility session.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the maximum aggregate downlink bit rate that the peer
agrees to offer for that mobility session.
When a QoS option includes both the Per-Session-Agg-Max-DL-Bit-Rate
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the QoS-Traffic-Selector attribute does not apply to this
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 |S|E| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Per-Session-Agg-Max-DL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 3
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (6).
o Service (S) flag: This flag is used for extending the scope of the
target flows for Per-Session-Agg-Max-DL-Bit-Rate to the mobile
node's other mobility sessions sharing the same Service
Identifier. 3GPP Access Point Name (APN) is an example of a
Service Identifier, and that identifier is carried using the
Service Selection mobility option [RFC5149].
* When the (S) flag is set to a value of (1), then the Per-
Session-Agg-Max-DL-Bit-Rate is measured as an aggregate across
all the mobile node's other mobility sessions sharing the same
Service Identifier associated with this mobility session.
* When the (S) flag is set to a value of (0), then the target
flows are limited to the current mobility session.
* The (S) flag MUST NOT be set to a value of (1) when there is no
Service Identifier associated with the mobility session.
o Exclude (E) flag: This flag is used to request that the downlink
flows for which the network is providing Guaranteed-Bit-Rate
service be excluded from the target IP flows for which Per-
Session-Agg-Max-DL-Bit-Rate is measured.
* When the (E) flag is set to a value of (1), then the request is
to exclude the IP flows for which Guaranteed-DL-Bit-Rate
(Section 4.2.8) is negotiated from the flows for which Per-
Session-Agg-Max-DL-Bit-Rate is measured.
* When the (E) flag is set to a value of (0), then the request is
not to exclude any IP flows from the target IP flows for which
Per-Session-Agg-Max-DL-Bit-Rate is measured.
* When the (S) flag and (E) flag are both set to a value of (1),
then the request is to exclude all the IP flows sharing the
Service Identifier associated with this mobility session from
the target flows for which Per-Session-Agg-Max-DL-Bit-Rate is
measured.
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Per-Session-Agg-Max-DL-Bit-Rate: This is a 32-bit unsigned integer
that indicates the aggregate maximum downlink bit rate that is
requested/allocated for all the IP flows associated with that
mobility session. The measurement units for Per-Session-Agg-Max-
DL-Bit-Rate are bits per second.
4.2.4. Per-Mobility-Session Aggregate Maximum Uplink Bit Rate
This attribute, Per-Session-Agg-Max-UL-Bit-Rate, represents the
maximum uplink bit rate for the mobility session. It is a variant of
the "AMBR" term defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message [RFC7077]
sent by the local mobility anchor, it indicates the maximum aggregate
uplink bit rate that is being requested for that mobility session.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement [RFC7077]
message, it indicates the maximum aggregate uplink bit rate that the
peer agrees to offer for that mobility session.
When a QoS option includes both the Per-Session-Agg-Max-UL-Bit-Rate
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the QoS-Traffic-Selector attribute does not apply to this
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 |S|E| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Per-Session-Agg-Max-UL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 4
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (6).
o Service (S) flag: This flag is used for extending the scope of the
target flows for Per-Session-Agg-Max-UL-Bit-Rate to the mobile
node's other mobility sessions sharing the same Service
Identifier. 3GPP Access Point Name (APN) is an example of a
Service Identifier, and that identifier is carried using the
Service Selection mobility option [RFC5149].
* When the (S) flag is set to a value of (1), then the Per-
Session-Agg-Max-UL-Bit-Rate is measured as an aggregate across
all the mobile node's other mobility sessions sharing the same
Service Identifier associated with this mobility session.
* When the (S) flag is set to a value of (0), then the target
flows are limited to the current mobility session.
* The (S) flag MUST NOT be set to a value of (1) when there is no
Service Identifier associated with the mobility session.
o Exclude (E) flag: This flag is used to request that the uplink
flows for which the network is providing Guaranteed-Bit-Rate
service be excluded from the target IP flows for which Per-
Session-Agg-Max-UL-Bit-Rate is measured.
* When the (E) flag is set to a value of (1), then the request is
to exclude the IP flows for which Guaranteed-UL-Bit-Rate
(Section 4.2.9) is negotiated from the flows for which Per-
Session-Agg-Max-UL-Bit-Rate is measured.
* When the (E) flag is set to a value of (0), then the request is
not to exclude any IP flows from the target IP flows for which
Per-Session-Agg-Max-UL-Bit-Rate is measured.
* When the (S) flag and (E) flag are both set to a value of (1),
then the request is to exclude all the IP flows sharing the
Service Identifier associated with this mobility session from
the target flows for which Per-Session-Agg-Max-UL-Bit-Rate is
measured.
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Per-Session-Agg-Max-UL-Bit-Rate: This is a 32-bit unsigned integer
that indicates the aggregate maximum uplink bit rate that is
requested/allocated for all the IP flows associated with that
mobility session. The measurement units for Per-Session-Agg-Max-
UL-Bit-Rate are bits per second.
4.2.5. Allocation and Retention Priority
This attribute, Allocation-Retention-Priority, represents allocation
and retention priority for the mobility session or a set of IP flows.
It is defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When the QoS option includes both the Allocation-Retention-Priority
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the Allocation-Retention-Priority attribute is to be applied at
a flow level. The traffic selector in the QoS-Traffic-Selector
attribute identifies the target flows.
When the QoS option including the Allocation-Retention-Priority
attribute does not include the QoS-Traffic-Selector attribute
(Section 4.2.10), then the Allocation-Retention-Priority attribute is
to be applied to all the IP flows associated with that mobility
session.
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 | PL |PC |PV |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 5
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (2).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Priority-Level (PL): This is a 4-bit unsigned integer value. It
is used to decide whether a mobility session establishment or
modification request can be accepted; this is typically used for
admission control of Guaranteed Bit Rate traffic in case of
resource limitations. The priority level can also be used to
decide which existing mobility session to preempt during resource
limitations. The priority level defines the relative timeliness
of a resource request.
Values 1 to 15 are defined, with value 1 as the highest level of
priority.
Values 1 to 8 should only be assigned for services that are
authorized to receive prioritized treatment within an operator
domain. Values 9 to 15 may be assigned to resources that are
authorized by the home network and thus applicable when a mobile
node is roaming.
o Preemption-Capability (PC): This is a 2-bit unsigned integer
value. It defines whether a service data flow can get resources
that were already assigned to another service data flow with a
lower priority level. The following values are defined:
Enabled (0): This value indicates that the service data flow is
allowed to get resources that were already assigned to another
IP data flow with a lower priority level.
Disabled (1): This value indicates that the service data flow
is not allowed to get resources that were already assigned to
another IP data flow with a lower priority level. The values
(2) and (3) are reserved.
o Preemption-Vulnerability (PV): This is a 2-bit unsigned integer
value. It defines whether a service data flow can lose the
resources assigned to it in order to admit a service data flow
with a higher priority level. The following values are defined:
Enabled (0): This value indicates that the resources assigned
to the IP data flow can be preempted and allocated to a service
data flow with a higher priority level.
Disabled (1): This value indicates that the resources assigned
to the IP data flow shall not be preempted and allocated to a
service data flow with a higher priority level. The values (2)
and (3) are reserved.
4.2.6. Aggregate Maximum Downlink Bit Rate
This attribute, Aggregate-Max-DL-Bit-Rate, represents the maximum
downlink bit rate for the mobility session. It is a variant of the
"AMBR" term defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by
the local mobility anchor, it indicates the maximum aggregate bit
rate for downlink IP flows that is being requested.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the maximum aggregate downlink bit rate that the peer
agrees to offer.
When a QoS option includes both the Aggregate-Max-DL-Bit-Rate
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the Aggregate-Max-DL-Bit-Rate attribute is to be enforced at a
flow level, and the traffic selectors present in the QoS-Traffic-
Selector attribute identify those target flows.
When the QoS option that includes the Aggregate-Max-DL-Bit-Rate
attribute does not include the QoS-Traffic-Selector attribute
(Section 4.2.10), then the Aggregate-Max-DL-Bit-Rate attribute is to
be applied to all the IP flows associated with the mobility session.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Aggregate-Max-DL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 6
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (6).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Aggregate-Max-DL-Bit-Rate: This is a 32-bit unsigned integer that
indicates the aggregate maximum downlink bit rate that is
requested/allocated for downlink IP flows. The measurement units
for Aggregate-Max-DL-Bit-Rate are bits per second.
4.2.7. Aggregate Maximum Uplink Bit Rate
This attribute, Aggregate-Max-UL-Bit-Rate, represents the maximum
uplink bit rate for the mobility session. It is a variant of the
"AMBR" term defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by
the local mobility anchor, it indicates the maximum aggregate uplink
bit rate that is being requested.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the maximum aggregate uplink bit rate that the peer agrees
to offer.
When a QoS option includes both the Aggregate-Max-UL-Bit-Rate
attribute and the QoS-Traffic-Selector attribute (Section 4.2.10),
then the Aggregate-Max-UL-Bit-Rate attribute is to be enforced at a
flow level, and the traffic selectors present in the QoS-Traffic-
Selector attribute identify those target flows.
When the QoS option that includes the Aggregate-Max-UL-Bit-Rate
attribute does not include the QoS-Traffic-Selector attribute
(Section 4.2.10), then the Aggregate-Max-UL-Bit-Rate attribute is to
be applied to all the IP flows associated with the mobility session.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Aggregate-Max-UL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 7
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (6).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Aggregate-Max-UL-Bit-Rate: This is a 32-bit unsigned integer that
indicates the aggregate maximum uplink bit rate that is requested/
allocated for all the IP flows associated with that mobility
session. The measurement units for Aggregate-Max-UL-Bit-Rate are
bits per second.
4.2.8. Guaranteed Downlink Bit Rate
This attribute, Guaranteed-DL-Bit-Rate, represents the assured bit
rate on the downlink path that will be provided for a set of IP flows
associated with a mobility session. It is a variant of the "GBR"
term defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by
the local mobility anchor, it indicates the guaranteed downlink bit
rate that is being requested.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the guaranteed downlink bit rate that the peer agrees to
offer.
When a QoS option includes both the Guaranteed-DL-Bit-Rate attribute
and the QoS-Traffic-Selector attribute (Section 4.2.10), then the
Guaranteed-DL-Bit-Rate attribute is to be enforced at a flow level,
and the traffic selectors present in the QoS-Traffic-Selector
attribute identify those target flows.
When the QoS option that includes the Guaranteed-DL-Bit-Rate
attribute does not include the QoS-Traffic-Selector attribute
(Section 4.2.10), then the Guaranteed-DL-Bit-Rate attribute is to be
applied to all the IP flows associated with the mobility session.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Guaranteed-DL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 8
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (6).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Guaranteed-DL-Bit-Rate: This is a 32-bit unsigned integer that
indicates the guaranteed bandwidth in bits per second for downlink
IP flows. The measurement units for Guaranteed-DL-Bit-Rate are
bits per second.
4.2.9. Guaranteed Uplink Bit Rate
This attribute, Guaranteed-UL-Bit-Rate, represents the assured bit
rate on the uplink path that will be provided for a set of IP flows
associated with a mobility session. It is a variant of the "GBR"
term defined in Section 2.2.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
only be a single instance of this attribute present in a QoS option.
When this attribute is present in a Proxy Binding Update sent by a
mobile access gateway or in an Update Notification message sent by
the local mobility anchor, it indicates the guaranteed uplink bit
rate that is being requested.
When this attribute is present in a Proxy Binding Acknowledgement
message or in an Update Notification Acknowledgement message, it
indicates the guaranteed uplink bit rate that the peer agrees to
offer.
When a QoS option includes both the Guaranteed-UL-Bit-Rate attribute
and the QoS-Traffic-Selector attribute (Section 4.2.10), then the
Guaranteed-UL-Bit-Rate attribute is to be enforced at a flow level,
and the traffic selectors present in the QoS-Traffic-Selector
attribute identify those target flows.
When the QoS option that includes the Guaranteed-UL-Bit-Rate
attribute does not include the QoS-Traffic-Selector attribute
(Section 4.2.10), then the Guaranteed-UL-Bit-Rate attribute is to be
applied to all the IP flows associated with the mobility session.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Guaranteed-UL-Bit-Rate |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 9
o Length: The length of the attribute in octets, excluding the Type
and Length fields. This value is set to (6).
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Guaranteed-UL-Bit-Rate: This is a 32-bit unsigned integer that
indicates the guaranteed bandwidth in bits per second for uplink
IP flows. The measurement units for Guaranteed-UL-Bit-Rate are
bits per second.
4.2.10. QoS Traffic Selector
This attribute, QoS-Traffic-Selector, includes the parameters used to
match packets for a set of IP flows.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute.
When a QoS option that includes the QoS-Traffic-Selector also
includes any one or more of the attributes Allocation-Retention-
Priority (Section 4.2.5), Aggregate-Max-DL-Bit-Rate (Section 4.2.6),
Aggregate-Max-UL-Bit-Rate (Section 4.2.7), Guaranteed-DL-Bit-Rate
(Section 4.2.8), and Guaranteed-UL-Bit-Rate (Section 4.2.9), then
those included attributes are to be enforced at a flow level, and the
traffic selectors present in the QoS-Traffic-Selector attribute
identify those target flows. Furthermore, the DSCP marking in the
QoS option is to be applied only to a partial set of the mobile
node's IP flows, and the traffic selectors present in the QoS-
Traffic-Selector attribute identify those target flows.
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 | TS Format |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Traffic Selector ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 10
o Length: The length of the attribute in octets, excluding the Type
and Length fields.
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o TS Format: An 8-bit unsigned integer indicating the Traffic
Selector Format. The values are allocated from the "Traffic
Selector Format" namespace for the traffic selector sub-option
defined in [RFC6089]; those defined in [RFC6089] are repeated here
for clarity. Value (0) is reserved and MUST NOT be used. When
the value of the TS Format field is set to (1), the format that
follows is the IPv4 Binary Traffic Selector specified in
Section 3.1 of [RFC6088], and when the value of TS Format field is
set to (2), the format that follows is the IPv6 Binary Traffic
Selector specified in Section 3.2 of [RFC6088].
o Traffic Selector: variable-length field for including the traffic
specification identified by the TS format field.
4.2.11. QoS Vendor-Specific Attribute
This attribute is used for carrying vendor-specific QoS attributes.
The interpretation and the handling of this option are specific to
the vendor implementation.
This attribute can be included in the Quality-of-Service option
defined in Section 4.1, and it is an optional attribute. There can
be multiple instances of this attribute with different sub-type
values present in a single QoS option.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Vendor ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Type | ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: 11
o Length: The length of the attribute in octets, excluding the Type
and Length fields.
o Reserved: This field is unused for now. The value MUST be
initialized by the sender to 0 and MUST be ignored by the
receiver.
o Vendor ID: The Vendor ID is the SMI (Structure of Management
Information) Network Management Private Enterprise Code of the
IANA-maintained "Private Enterprise Numbers" registry [SMI].
o Sub-Type: An 8-bit field indicating the type of vendor-specific
information carried in the option. The namespace for this sub-
type is managed by the vendor identified by the Vendor ID field.
4.3. New Status Code for Proxy Binding Acknowledgement
This document defines the following new status code value for use in
Proxy Binding Acknowledgement message.
CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service Request):
179
4.4. New Notification Reason for Update Notification Message
This document defines the following new Notification Reason value for
use in Update Notification message.
QOS_SERVICE_REQUEST (QoS Service Requested): 5
4.5. New Status Code for Update Notification Acknowledgement Message
This document defines the following new status code value for use in
Update Notification Acknowledgement message.
CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service Request):
130
5. Protocol Considerations
5.1. 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],
can be extended to store a list of negotiated Quality-of-Service
requests to be enforced. There can be multiple such entries, and
each entry must include the Service Request Identifier, DSCP
value, and the attributes defined in Section 4.2.
LMA Receiving a QoS Service Request:
o On receiving a Proxy Binding Update message with an instance of
the Quality-of-Service option included in the message and the
Operational Code field of the Quality-of-Service option set to
QUERY, then the local mobility anchor includes all the Quality-of-
Service option(s) reflecting the currently negotiated QoS Service
Requests for that mobility session in the response message. The
Operational Code field in each of the Quality-of-Service
option(s), which is included in the response message, is set to
RESPONSE.
o On receiving a Proxy Binding Update message with one or more
instances of the Quality-of-Service option included in the message
and the Operational Code field set to ALLOCATE, the local mobility
anchor processes the option(s) and determines if the QoS Service
Request for the proposed QoS Service Request(s) can be met. Each
instance of the Quality-of-Service option represents a specific
QoS Service Request. This determination to accept the request(s)
can be based on policy configured on the local mobility anchor,
available network resources, or other considerations.
o If the local mobility anchor can support the proposed QoS Service
Requests in entirety, then it sends a Proxy Binding
Acknowledgement message with a status code value of (0).
* The message includes all the Quality-of-Service option
instances copied (including all the option content) from the
received Proxy Binding Update message. The local mobility
anchor assigns a Service Request Identifier to each Service
Request and sets the SR-ID field of each included Quality-of-
Service option accordingly.
* The Operational Code field in each of the Quality-of-Service
option(s) is set to RESPONSE.
* The local mobility anchor should enforce the Quality-of-Service
rules for all the negotiated QoS Service Requests on the mobile
node's uplink and downlink traffic.
o If the local mobility anchor cannot support any of the requested
QoS Service Requests in entirety, it rejects the request and sends
a Proxy Binding Acknowledgement message with the status code value
set to CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet QoS Service
Request).
* Since the local mobility anchor cannot support the requested
QoS services for that mobile node, the Proxy Binding
Acknowledgement message will not include any Quality-of-Service
options. This serves as an indication to the mobile access
gateway that QoS services are not supported for that mobile
node.
* The denial of a QoS Service Request MUST NOT result in removal
of the mobility session for that mobile node.
o If the local mobility anchor can support QoS services for the
mobile node, but only with lower quality values than indicated in
the QoS attributes of a received QoS option or only for some of
the received QoS Service Requests, the local mobility anchor
includes the QoS option for the supported QoS Service Requests in
the Proxy Binding Acknowledgement message with an updated set of
QoS attributes.
* If the local mobility anchor cannot support some of the
received QoS Service Requests for that mobile node, then the
Quality-of-Service option for these QoS Service Requests is not
included in the Proxy Binding Acknowledgement message. This
serves as an indication to the mobile access gateway that a
particular QoS Service Request is not supported for that mobile
node. This includes the case where the attributes in a QoS
option have conflicting requirements, for example, Per-Session-
Agg-Max-UL-Bit-Rate is lower than Guaranteed-UL-Bit-Rate.
* The local mobility anchor includes only QoS options in the
Proxy Binding Acknowledgement message for supported QoS
attributes. The contents of each option (including the QoS
attributes) reflect the QoS service parameters that the local
mobility anchor can support for that mobile node. The local
mobility anchor sets the values of each supported QoS attribute
according to the level of QoS it can support for the mobile
node. The Service Request Identifier in each of the included
QoS options is set to a value of (0). The Operational Code
field in each of the included Quality-of-Service option(s) is
set to NEGOTIATE. This serves as an indication for the mobile
access gateway to resend the Proxy Binding Update message with
the revised QoS parameters.
LMA Sending a QoS Service Request:
o The local mobility anchor, at any time, can initiate a QoS Service
Request for a mobile node by sending an Update Notification
message [RFC7077]. The Notification Reason in the Update
Notification message is set to a value of QOS_SERVICE_REQUEST, and
the Acknowledgement Requested (A) flag is set to a value of (1).
* New QoS Service Request:
+ The message includes one or more instances of the Quality-
of-Service option. Each instance of the option will include
one or more QoS attributes.
+ The Operational Code field in the Quality-of-Service option
is set to ALLOCATE.
+ The Service Request Identifier is set to the allocated
value.
+ The DSCP field in the Traffic Class (TC) field is set to the
requested DSCP value.
* Modification of an existing QoS Service Request:
+ The message includes one or more instances of the Quality-
of-Service option with the QoS attributes reflecting the
updated values in the attributes and the updated list of
attributes.
+ The Operational Code field in the Quality-of-Service option
is set to MODIFY.
+ The Service Request Identifier is set to a value that was
allocated for that QoS Service Request.
+ The DSCP field in the Traffic Class (TC) field is set to the
requested DSCP value.
* Deletion of an existing QoS Service Request:
+ The message includes the Quality-of-Service option(s) with
the relevant QoS attributes.
+ The Operational Code field in the Quality-of-Service option
is set to DE-ALLOCATE.
+ The Service Request Identifier is set to a value that was
allocated for that QoS Service Request.
+ The DSCP field in the Traffic Class (TC) field is set to the
DSCP value associated with that request.
* Query for the previously negotiated QoS Service Requests:
+ The message includes a single instance of the Quality-of-
Service option without including any QoS attributes.
+ The Operational Code field in the Quality-of-Service option
is set to QUERY.
+ The Service Request Identifier is set to a value of (0).
+ The DSCP field in the Traffic Class (TC) field is set to a
value of (0).
o Handling a Response to the QoS Service Request:
* If the received Update Notification Acknowledgement [RFC7077]
message has the Status Code field set to a value (0), the local
mobility anchor should enforce the Quality-of-Service rules for
the negotiated QoS parameters on the mobile node's uplink and
downlink traffic.
* If the received Update Notification Acknowledgement message has
the Status Code field set to a value
CANNOT_MEET_QOS_SERVICE_REQUEST, the local mobility anchor
applies the following considerations:
+ The denial of a QoS Service Request results in removal of
any QoS state associated with that request.
+ If the message did not include any Quality-of-Service
option(s), then it is an indication from the mobile access
gateway that QoS services are not enabled for the mobile
node.
+ If the Operational Code field in the Quality-of-Service
option is set to a value of NEGOTIATE and the message
includes one or more instances of the Quality-of-Service
option, but the option contents reflect a downgraded/revised
set of QoS parameters, then the local mobility anchor MAY
choose to agree to proposed QoS Service Request by resending
a new Update Notification message with the updated Quality-
of-Service option(s).
General Considerations:
o Any time the local mobility anchor removes a mobile node's
mobility session by removing a Binding Cache entry [RFC5213] for
which QoS resources have been previously allocated, those
allocated resources are released.
o Any time the local mobility anchor receives a Proxy Binding Update
with HI hint = 3 (inter-MAG handover), the local mobility anchor
when sending a Proxy Binding Acknowledgement message includes the
QoS option(s) for each of the QoS Service Requests that are active
for that mobile node. This allows the mobile access gateway to
allocate QoS resources on the current path. This is relevant for
the scenario where a mobile node performs a handover to a new
mobile access gateway that is unaware of the previously negotiated
QoS services.
5.2. 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], can be extended to store a list of negotiated Quality-
of-Service requests to be enforced. There can be multiple such
entries, and each entry must include the Service Request
Identifier, DSCP value and the attributes defined in Section 4.2.
MAG Receiving a QoS Service Request:
o On receiving an Update Notification message with one or more
instances of the Quality-of-Service option included in the
message, the mobile access gateway processes the option(s) and
determines if the QoS Service Request for the proposed QoS Service
Request(s) can be met. Each instance of the Quality-of-Service
option represents a specific QoS Service Request. This
determination to accept the request(s) can be based on policy
configured on the mobile access gateway, available network
resources, or other considerations.
o If the mobile access gateway can support the proposed QoS Service
Requests in entirety, then it sends an Update Notification
Acknowledgement message with a status code value of (0).
* The message includes all the Quality-of-Service option
instances copied (including all the option content) from the
received Update Notification message. However, if the
Operational Code field in the request is a QUERY, then the
message includes all the Quality-of-Service option(s)
reflecting the currently negotiated QoS Service Requests for
that mobility session.
* The Operational Code field in each of the Quality-of-Service
option(s) is set to RESPONSE.
* The mobile access gateway should enforce the Quality-of-Service
rules for all the negotiated QoS Service Requests on the mobile
node's uplink and downlink traffic.
o If the mobile access gateway cannot support any of the requested
QoS Service Requests in entirety, then it rejects the request and
sends an Update Notification Acknowledgement message with the
status code set to CANNOT_MEET_QOS_SERVICE_REQUEST (Cannot meet
QoS Service Request).
* The denial for QoS Service Request MUST NOT result in removal
of the mobility session for that mobile node.
* The Update Notification Acknowledgement message may include the
Quality-of-Service option(s) based on the following
considerations.
+ If the mobile access gateway cannot support QoS services for
that mobile node, then the Quality-of-Service option is not
included in the Update Notification Acknowledgement message.
This serves as an indication to the local mobility anchor
that QoS services are not supported for that mobile node.
+ If the mobile access gateway can support QoS services for
the mobile node, but only with lower quality values than
indicated in the QoS attributes of a received QoS option,
the mobile access gateway includes the QoS option in the
Update Notification Acknowledgement message with an updated
set of QoS attributes. The mobile access gateway sets the
values of each QoS attribute according to the level of QoS
it can support for the mobile node. The mobile access
gateway includes only QoS options in the Update Notification
Acknowledgement message for supported QoS attributes. If
the mobile access gateway receives one or multiple QoS
options, whose QoS attributes are not supported, it omits
these QoS options in the Update Notification Acknowledgement
message. This includes the case where the attributes in a
QoS option have conflicting requirements, for example, Per-
Session-Agg-Max-UL-Bit-Rate is lower than Guaranteed-UL-Bit-
Rate. The contents of each option (including the QoS
attributes) reflect the QoS service parameters that the
mobile access gateway can support for that mobile node. The
Operational Code field in each of the Quality-of-Service
option(s) is set to NEGOTIATE. This serves as an indication
to the local mobility anchor to resend the Update
Notification message with the revised QoS parameters.
MAG Sending a QoS Service Request:
o The mobile access gateway, at any time, can initiate a QoS Service
Request for a mobile node by sending a Proxy Binding Update
message. The QoS Service Request can be initiated as part of the
initial Binding registration or during Binding re-registrations.
* New QoS Service Request:
+ The message includes one or more instances of the Quality-
of-Service option. Each instance of the option will include
one or more QoS attributes.
+ The Operational Code field in each of the Quality-of-Service
option is set to ALLOCATE.
+ The Service Request Identifier is set to a value of (0).
+ The DSCP value in the Traffic Class field reflects the
requested DSCP value.
* Modification of an existing QoS Service Request:
+ The message includes one or more instances of the Quality-
of-Service option with the QoS attributes reflecting the
updated values in the attributes and the updated list of
attributes.
+ The Operational Code field in the Quality-of-Service option
is set to MODIFY.
+ The Service Request Identifier is set to a value that was
allocated for that QoS Service Request.
+ The DSCP field in the Traffic Class (TC) field is set to the
requested DSCP value.
* Deletion of an existing QoS Service Request:
+ The message includes the Quality-of-Service option(s) with
the relevant QoS attributes.
+ The Operational Code field in the Quality-of-Service option
is set to DE-ALLOCATE.
+ The Service Request Identifier is set to a value that was
allocated for that QoS Service Request.
+ The DSCP field in the Traffic Class (TC) field is set to the
DSCP value associated with that request.
* Query for the previously negotiated QoS Service Requests:
+ The message includes a single instance of the Quality-of-
Service option without including any QoS attributes.
+ The Operational Code field in the Quality-of-Service option
is set to QUERY.
+ The Service Request Identifier is set to a value of (0).
+ The DSCP field in the Traffic Class (TC) field is set to a
value of (0).
o Handling a Response to the QoS Service Request:
* If the received Proxy Binding Acknowledgement message has the
Status Code field set to a value of (0), the mobile access
gateway should enforce the Quality-of-Service rules for the
negotiated QoS parameters on the mobile node's uplink and
downlink traffic.
* If the received Proxy Binding Acknowledgement message has the
Status Code field set to a value of
CANNOT_MEET_QOS_SERVICE_REQUEST, the mobile access gateway
applies the following considerations.
+ The denial of a QoS Service Request results in removal of
any QoS state associated with that request.
+ If the message did not include any Quality-of-Service
option(s), then it is an indication from the local mobility
anchor that QoS services are not enabled for the mobile
node.
+ If the Operational Code field in the Quality-of-Service
option is set to a value of NEGOTIATE and the message
includes one or more instances of the Quality-of-Service
option, but the option contents reflect a downgraded/revised
set of QoS parameters, then the mobile access gateway MAY
choose to agree to proposed QoS Service Request by resending
a new Proxy Binding Update message with the updated Quality-
of-Service option.
* General Considerations:
+ There can be more than one QoS Service Request in a single
message. If so, the message includes an instance of a
Quality-of-Service option for each of those Service
Requests. Furthermore, the DSCP value is different in each
of those requests.
+ Any time the mobile access gateway removes a mobile node's
mobility session by removing a Binding Update List entry
[RFC5213] for which QoS resources have been previously
allocated, those allocated resources are released.
6. QoS Services in Integrated WLAN-3GPP Networks
6.1. Technical Scope and Procedure
The QoS option specified in this document can provide the equivalent
level of QoS information defined in 3GPP, which is used to enforce
QoS policies for IP flows that have been established while the mobile
node is attached to WLAN access or moved from 3GPP to WLAN access.
The QoS classification defined by the 3GPP specification [TS23.207]
[TS29.212] is provided by Differentiated Services techniques in the
IP transport network. The QoS classification used in the IP
transport network is further translated to WLAN QoS-specific
techniques in the WLAN access using appropriate WLAN QoS
specifications [IEEE802.11aa-2012] [WMM1.2.0]. The details are
described in Appendix A and Appendix B.
Figure 6 illustrates a generalized architecture where the QoS option
can be used. The QoS policies could be retrieved from a Policy
Control Function (PCF), such as defined in current cellular mobile
communication standards, which aims to assign an appropriate QoS
class to a mobile node's individual flows. Alternatively, more
static and default QoS rules could be made locally available, e.g.,
on a local mobility anchor, through administration.
Non-cellular access | Cellular Core Network Cellular
(e.g., WLAN) | (e.g., EPC) Access
| (e.g.,
| +-----------+ EUTRAN)
| | PCF |
| |(e.g.,PCRF)|
+----+ | +-----+-----+
|WiFi| (I) | |
| AP |---+ +---+---+ | | ((O))
+----+ | |WiFi AR| | PMIPv6 +-----+ +---+ |
+----+ (MAG) +=|============| LMA |=====|MAG+--|
| | WLC | | tunnel +-----+ +---+ |
+----+ | +-------+ | //
|WiFi|---+ | //
| AP | | //
+----+ (II) | //
+-------+ | //
+----+ +------+ |WiFi AR| | //
|WiFi+----+ WLC +------+ (MAG) |=|=======//
| AP | | | | | |
+----+ +------+ +------ + |
^ ^ |
| | |
+------------+
QoS inter-working
Figure 6: Architecture for QoS Inter-Working between Cellular Access
and Non-Cellular Access
During a mobile node's handover from cellular access to non-cellular
access, e.g., a wireless LAN (WLAN) radio access network, the mobile
node's QoS policy rules, as previously established on the local
mobility anchor for the mobile node's communication through the
cellular access network, are moved to the handover target mobile
access gateway serving the non-cellular access network. Such a non-
cellular mobile access gateway can have an access-technology-specific
controller or function co-located, e.g., a Wireless LAN Controller
(WLC), as depicted in option (I) of Figure 6. Alternatively, the
access-specific architecture can be distributed, and the access-
technology-specific control function is located external to the
mobile access gateway, as depicted in option (II). In this case, the
mobile access gateway and the access-technology-specific control
function (e.g., the WLC) must provide some protocol for QoS inter-
working. Details of such inter-working are out of the scope of this
specification.
6.2. Relevant QoS Attributes
The QoS Option shall at least contain a DSCP value being associated
with IP flows of a mobility session. The DSCP value should
correspond to the 3GPP QoS Class Index (QCI), which identifies the
type of service in terms of QoS characteristics (e.g., conversational
voice, streaming video, signaling, and best effort); more details on
DSCP and QCI mapping are given in Appendix A. Optional QoS
information could also be added. For instance, in order to comply
with the bearer model defined in 3GPP [TS23.203], the following QoS
parameters are conveyed for each PMIPv6 mobility session:
o Default, non-GBR bearer (QCI=5-9)
* DSCP=(BE, AF11, AF21, AF31, AF32)
* Per-MN AMBR-UL/DL
* Per-Session AMBR-UL/DL {S=1,E=1}
* AARP
APN (Access Point Name) is provided via the Service Selection ID
defined in [RFC5149]. If APN is not interpreted by Wi-Fi AP, the
latter will police only based on Per-MN AMBR-UL/DL (without Per-
Session AMBR-UL/DL) on the Wi-Fi link.
o Dedicated, GBR bearer (QCI=1-4)
* DSCP=(EF, AF41)
* GBR-UL/DL
* MBR-UL/DL
* AARP
* TS
Wi-Fi AP will perform the policy enforcement with the minimum bit
rate=GBR and the maximum bit rate=MBR.
o Dedicated, non-GBR bearer (QCI=5-9)
* DSCP=(BE, AF11, AF21, AF31, AF32)
* Per-MN AMBR-UL/DL
* Per-Session AMBR-UL/DL {S=1,E=1}
* AARP
* TS
If APN is not interpreted by Wi-Fi AP, it will police based only
on Per-MN AMBR-UL/DL (without Per-Session AMBR-UL/DL) on the Wi-Fi
link.
If DSCP values follow the 3GPP specification and deployment, the code
point can carry intrinsically additional attributes according to
Figure 7 in Appendix A.
For some optional QoS attributes, the signaling can differentiate
enforcement per mobility session and per IP flow. For the latter, as
long as the AMBR constraints are met, the rule associated with the
identified flow(s) overrules the aggregated rules that apply per
mobile node or per mobility session. Additional attributes can be
appended to the QoS option, but their definition and specification is
out of scope of this document and are left as considerations for
actual deployment.
7. IANA Considerations
IANA has completed the following actions:
o Action-1: This specification defines a new mobility option, the
Quality-of-Service (QoS) option. The format of this option is
described in Section 4.1. The type value 58 for this mobility
option has been allocated from the "Mobility Options" registry at
<http://www.iana.org/assignments/mobility-parameters>.
o Action-2: This specification defines a new mobility attribute
format, the Quality-of-Service attribute. The format of this
attribute is described in Section 4.2. This attribute can be
carried in the Quality-of-Service mobility option. The type
values for this attribute are managed by IANA in a new registry,
the "Quality-of-Service Attribute Registry". This registry is
maintained under the "Mobile IPv6 parameters" registry at
<http://www.iana.org/assignments/mobility-parameters>. This
specification reserves the type values listed below. All other
values (12 - 254) are unassigned and may be assigned by IANA using
the Specification Required policy [RFC5226]. The Designated
Expert reviewing the value assignment is expected to verify that
the protocol extension follows the Proxy Mobile IPv6 architecture
and does not raise backward-compatibility issues with existing
deployments.
+=====+=================================+=================+
|Value| Description | Reference |
+=====+=================================+=================+
| 0 | Reserved | RFC 7222 |
+=====+===================================================+
| 1 | Per-MN-Agg-Max-DL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 2 | Per-MN-Agg-Max-UL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 3 | Per-Session-Agg-Max-DL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 4 | Per-Session-Agg-Max-UL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 5 | Allocation-Retention-Priority | RFC 7222 |
+=====+===================================================+
| 6 | Aggregate-Max-DL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 7 | Aggregate-Max-UL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 8 | Guaranteed-DL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 9 | Guaranteed-UL-Bit-Rate | RFC 7222 |
+=====+===================================================+
| 10 | QoS-Traffic-Selector | RFC 7222 |
+=====+===================================================+
| 11 | QoS-Vendor-Specific-Attribute | RFC 7222 |
+=====+===================================================+
| 255 | Reserved | RFC 7222 |
+=====+===================================================+
o Action-3: This document defines a new status code,
CANNOT_MEET_QOS_SERVICE_REQUEST (179), for use in Proxy Binding
Acknowledgement messages, as described in Section 4.3. This value
has been assigned from the "Status Codes" registry at
<http://www.iana.org/assignments/mobility-parameters>.
o Action-4: This document defines a new Notification Reason,
QOS_SERVICE_REQUEST (5), for use in Update Notification messages
[RFC7077] as described in Section 4.4. This value has been
assigned from the "Update Notification Reasons Registry" at
<http://www.iana.org/assignments/mobility-parameters>.
o Action-5: This document defines a new status code,
CANNOT_MEET_QOS_SERVICE_REQUEST (130), for use in Update
Notification Acknowledgement messages [RFC7077] as described in
Section 4.5. This value has been assigned from the "Update
Notification Acknowledgement Status Registry" at
<http://www.iana.org/assignments/mobility-parameters>.
8. Security Considerations
The Quality-of-Service option defined in this specification is for
use in Proxy Binding Update, Proxy Binding Acknowledgement, Update
Notification, and Update Notification Acknowledgement messages. This
option is carried in these messages like any other mobility header
option. [RFC5213] and [RFC7077] identify the security considerations
for these signaling messages. When included in these signaling
messages, the Quality-of-Service option does not require additional
security considerations.
9. Acknowledgements
The authors of this document thank the members of NetExt working
group for the valuable feedback to different versions of this
specification. In particular, the authors want to thank Basavaraj
Patil, Behcet Sarikaya, Charles Perkins, Dirk von Hugo, Mark Grayson,
Tricci So, Ahmad Muhanna, Pete McCann, Byju Pularikkal, John
Kaippallimalil, Rajesh Pazhyannur, Carlos J. Bernardos Cano, Michal
Hoeft, Ryuji Wakikawa, Liu Dapeng, Seil Jeon, and Georgios
Karagiannis.
The authors would like to thank all the IESG reviewers, especially,
Ben Campbell, Barry Leiba, Jari Arkko, Alissa Cooper, Stephen
Farrell, Ted Lemon, and Alia Atlas for their valuable comments and
suggestions to improve this specification.
Finally, the authors would like to express sincere and profound
appreciation to our Internet Area Director, Brian Haberman, for his
guidance and great support in allowing us to complete this work.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
[RFC5844] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
Mobile IPv6", RFC 5844, May 2010.
[RFC6088] Tsirtsis, G., Giarreta, G., Soliman, H., and N. Montavont,
"Traffic Selectors for Flow Bindings", RFC 6088, January
2011.
[RFC7077] Krishnan, S., Gundavelli, S., Liebsch, M., Yokota, H., and
J. Korhonen, "Update Notifications for Proxy Mobile IPv6",
RFC 7077, November 2013.
10.2. Informative References
[GSMA.IR.34]
GSMA, "Guidelines for IPX Provider networks (Previously
Inter-Service Provider IP Backbone Guidelines)", Official
Document PRD IR.34, May 2013.
[IEEE802.11-2012]
IEEE, "Part 11: Wireless LAN Medium Access Control (MAC)
and Physical Layer (PHY) Specifications", 2012.
[IEEE802.11aa-2012]
IEEE, "Part 11: Wireless LAN Medium Access Control (MAC)
and Physical Layer (PHY) Specifications, Amendment 2: MAC
Enhancements for Robust Audio Video Streaming", 2012.
[IEEE802.11e-2005]
IEEE, "Part 11: Wireless LAN Medium Access Control (MAC)
and Physical Layer (PHY) Specifications, Amendment 8:
Medium Access Control (MAC) Quality of Service (QoS)
Enhancements", 2005.
[RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black,
"Definition of the Differentiated Services Field (DS
Field) in the IPv4 and IPv6 Headers", RFC 2474, December
1998.
[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
and W. Weiss, "An Architecture for Differentiated
Services", RFC 2475, December 1998.
[RFC2983] Black, D., "Differentiated Services and Tunnels", RFC
2983, October 2000.
[RFC4594] Babiarz, J., Chan, K., and F. Baker, "Configuration
Guidelines for DiffServ Service Classes", RFC 4594, August
2006.
[RFC5149] Korhonen, J., Nilsson, U., and V. Devarapalli, "Service
Selection for Mobile IPv6", RFC 5149, February 2008.
[RFC6089] Tsirtsis, G., Soliman, H., Montavont, N., Giaretta, G.,
and K. Kuladinithi, "Flow Bindings in Mobile IPv6 and
Network Mobility (NEMO) Basic Support", RFC 6089, January
2011.
[SMI] IANA, "PRIVATE ENTERPRISE NUMBERS", SMI Network Management
Private Enterprise Codes, April 2014,
<http://www.iana.org/assignments/enterprise-numbers>.
[TS22.115] 3GPP, "Technical Specification Group Services and System
Aspects; Service aspects; Charging and billing", 3GPP TS
22.115, 2010.
[TS23.203] 3GPP, "Technical Specification Group Services and System
Aspects; Policy and charging control architecture", 3GPP
TS 23.203, 2013.
[TS23.207] 3GPP, "End-to-End Quality of Service (QoS) Concept and
Architecture, Release 10", 3GPP TS 23.207, 2011.
[TS23.402] 3GPP, "Technical Specification Group Services and System
Aspects; Architecture enhancements for non-3GPP accesses",
3GPP TS 23.402, 2012.
[TS29.212] 3GPP, "Policy and Charging Control over Gx/Sd Reference
Point, Release 11", 3GPP TS 29.212, 2011.
[WMM1.2.0] Wi-Fi Alliance, "Wi-Fi Multimedia Technical Specification
(with WMM-Power Save and WMM-Admission Control)", Version
1.2.0.
Appendix A. Information When Implementing 3GPP QoS in IP Transport
Network
A.1. Mapping Tables
Mapping between 3GPP QCI values and DSCP is defined in [GSMA.IR.34]
as follows.
+=====+================+===========================+======+
| QCI | Traffic Class | DiffServ Per-Hop-Behavior | DSCP |
+=====+================+===========================+======+
| 1 | Conversational | EF |101110|
+=====+===================================================+
| 2 | Conversational | EF |101110|
+=====+===================================================+
| 3 | Conversational | EF |101110|
+=====+===================================================+
| 4 | Streaming | AF41 |100010|
+=====+===================================================+
| 5 | Interactive | AF31 |011010|
+=====+===================================================+
| 6 | Interactive | AF32 |011100|
+=====+===================================================+
| 7 | Interactive | AF21 |010010|
+=====+===================================================+
| 8 | Interactive | AF11 |001010|
+=====+===================================================+
| 9 | Background | BE |000000|
+=====+===================================================+
Figure 7: QCI/DSCP Mapping Table
Mapping between QoS attributes defined in this document and 3GPP QoS
parameters is as follows.
+=======+===============================+=============+
|Section| PMIPv6 QoS | 3GPP QoS |
| | Attribute | Parameter |
+=======+===============================+=============+
| 4.2.1 | Per-MN-Agg-Max-DL-Bit-Rate | UE AMBR-DL |
+-------+-------------------------------+-------------+
| 4.2.2 | Per-MN-Agg-Max-UL-Bit-Rate | UE AMBR-UL |
+-------+-------------------------------+-------------+
| 4.2.3 |Per-Session-Agg-Max-DL-Bit-Rate| APN AMBR-DL |
| | Flags: (S=1, E=1) | |
+-------+-------------------------------+-------------+
| 4.2.4 |Per-Session-Agg-Max-UL-Bit-Rate| APN AMBR-UL |
| | Flags: (S=1, E=1) | |
+-------+-------------------------------+-------------+
| 4.2.5 | Allocation-Retention-Priority | ARP |
+-------+-------------------------------+-------------+
| 4.2.6 | Aggregate-Max-DL-Bit-Rate | MBR-DL |
+-------+-------------------------------+-------------+
| 4.2.7 | Aggregate-Max-UL-Bit-Rate | MBR-UL |
+-------+-------------------------------+-------------+
| 4.2.8 | Guaranteed-DL-Bit-Rate | GBR-DL |
+-------+-------------------------------+-------------+
| 4.2.9 | Guaranteed-UL-Bit-Rate | GBR-UL |
+-------+-------------------------------+-------------+
| 4.2.10| QoS-Traffic-Selector | TFT |
+-------+-------------------------------+-------------+
Figure 8: QoS Attributes and 3GPP QoS Parameters Mapping Table
A.2. Use Cases and Protocol Operations
The following subsections provide example message flow charts for
scenarios where the QoS option extensions will apply as described in
Section 6.1 to the protocol operation for QoS rules establishment
(Appendices A.2.1 and A.2.2) and to modification (Appendix A.2.3).
A.2.1. Handover of Existing QoS Rules
In Figure 9, the MN is first connected to the LTE network with a
multimedia session, such as a video call, with appropriate QoS
parameters set by the Policy Control Function. Then, the MN
discovers a Wi-Fi AP (e.g., at home or in a cafe) and switches to it,
provided that Wi-Fi access has a higher priority when available. Not
only is the session continued, but the QoS is also maintained after
moving to the Wi-Fi access. In order for that to happen, the LMA
delivers the QoS parameters according to the bearer type on the 3GPP
access to the MAG via the PMIPv6 signaling with the QoS option
(OC=ALLOCATE, SR-ID, QoS attributes, etc.). The equivalent QoS
treatment is provided by the Wi-Fi AP toward the MN on the Wi-Fi
link.
+--------+
|Policy |
|Control |
|Function|
+---+----+
|
+----+ +-------+ +---+----+
+--+ |LTE |_______| SGW | | PGW |
|MN|~~|eNB | | |==============| (LMA) |
+--+ +----+ +-------+ //+--------+
: //
: //
V +----+ +-------+ PMIPv6 //
+--+ |WiFi|_______| WLC |=========
|MN|~~| AP | | (MAG) | tunnel
+--+ +----+ +-------+
Figure 9: Handover Scenario (from LTE to WLAN)
Figure 10 shows an example of how the QoS rules can be conveyed and
enforced between the LMA and MN in the case of a handover from 3GPP
access to WLAN access.
+--+ +--+ +---+ +---+
|MN| |AP| |MAG| |LMA|
+--+ +--+ +---+ +---+
|| | | To |data
|+--detach | | cellular<-==data[DSCP]==-|<----
+----attach-----+ | access [QoS rules]
| |-INFO[MNattach]->| |
| | |-------PBU[handover]------>|
| | | |
| | |<--PBA[QoS option(OC=1 )]--|
| |<-INFO[QoSrules]-| |
| | | |
| Apply Establish Update
| mapped MN's uplink MN's downlink
| QoS rules DSCP rules DSCP rules
| | +===========================+
| | | |
| |(B) |(A) |data
|<--data[QC]----|<---data[DSCP]---|<-======data[DSCP]========-|<----
| | | |
| | | |data
|---data[QC]--->|-->data[DSCP]--->|-=======data[DSCP]=======->|--->
| |(C) |(D) |
| | | |
(A): Apply DSCP at link to AP
(B): Enforce mapped QoS rules to access technology
(C): Map MN-indicated QoS Class (QC) to DSCP on the AP-MAG link, or
validate MN-indicated QC and apply DSCP on the AP-MAG link
according to QoS rules
(D): Validate received DSCP and apply DSCP according to QoS rules
Figure 10: Handover of QoS Rules
A.2.2. Establishment of QoS Rules
A single operator has deployed both a fixed access network and a
mobile access network. In this scenario, the operator may wish a
harmonized QoS management on both accesses, but the fixed access
network does not implement a QoS control framework. So, the operator
chooses to rely on the 3GPP policy control function, which is a
standard framework to provide a QoS control, and to enforce the 3GPP
QoS policy on the Wi-Fi access network. The PMIP interface is used
to realize this QoS policy provisioning.
The use case is depicted on Figure 11. The MN first attaches to the
Wi-Fi network. During the attachment process, the LMA, which may
communicate with Policy Control Function (using procedures outside
the scope of this document), provides the QoS parameters to the MAG
via the QoS option (OC=ALLOCATE) in the PMIP signaling (i.e., PBA).
Subsequently, an application on the MN may trigger the request for
alternative QoS resources, e.g., by use of the WMM-API (Wi-Fi
Multimedia - API). The MN may request that traffic resources be
reserved using L2 signaling, e.g., sending an Add Traffic System
(ADDTS) message [IEEE802.11-2012]. The request is relayed to the
MAG, which includes the QoS parameters in the QoS option
(OC=ALLOCATE) on the PMIP signaling (i.e., the PBU initiated upon
flow creation). The LMA, in coordination with the PCF, can then
authorize the enforcement of such QoS policy. Then, the QoS
parameters are provided to the MAG via the QoS option (OC=ALLOCATE,
SR-ID, QoS attributes, etc.) in the PMIP signaling, and the
equivalent QoS treatment is provided towards the MN on the Wi-Fi
link.
|
|
| +--------+
| |Policy |
| |Control |
| |Function|
| +---+----+
| |
| +---+----+
+----+ +-------+ PMIPv6 | | PGW |
+--+ |WiFi|_______| WLC |========|=| (LMA) |
|MN|~~| AP | | (MAG) | tunnel | +--------+
+--+ +----+ +-------+ |
|
Wi-Fi Access |
Network | Cellular
| Network
|
Figure 11: QoS Policy Provisioning
Figure 12 shows an example of how the QoS rules can be conveyed and
enforced between the LMA and MN in the case of initial attachment to
WLAN access.
+--+ +--+ +---+ +---+
|MN| |AP|-------------|MAG|-----------------------|LMA|
+--+ +--+ +---+ +---+
| | | |
| | | |
+----attached---+ | [QoS rules]
| | | |
new session |(E) |(F) |data
|----data[QC]-->|---data[DSCPa]-->|-======data[DSCPb]=======->|--->
| | |--PBU[update,QoS option]-->|
| | | (ReReg) (OC=1) Validate and
| | | add QoS rule
| | |<----PBA[QoS option]----|
| |<-INFO[QoSrules]-| (OC=1, SR-ID)[QoS rules']
| | | |
| Apply Establish |
| adapted MN's uplink |
| QoS rules DSCP rules |
| | | |
| | | |
| | | |data
|<--data[QC]----|<---data[DSCP]---|<-======data[DSCP]========-|<----
| | | |
| | | |data
|---data[QC]--->|-->data[DSCP]--->|-=======data[DSCP]=======->|--->
| | | |
| | | |
(E): AP may enforce uplink QoS rules according to priority class
set by the MN
(F): MAG can enforce a default QoS class until the local mobility
anchor classifies the new flow (notified with PBA) or the mobile
access gateway classifies new flow and proposes the associated
QoS class to the local mobility anchor for validation (proposed
with PBU, notification of validation result with PBA)
Figure 12: Adding New QoS Service Request for MN-Initiated Flow
A.2.3. Dynamic Update to QoS Policy
A mobile node is attached to the WLAN access and has obtained QoS
parameters from the LMA for that mobility session. Having obtained
the QoS parameters, a new application, e.g., IP Multimedia Subsystems
(IMS) application, gets launched on the mobile node that requires
certain QoS support.
The application on the mobile node initiates the communications via a
dedicated network function (e.g., IMS Call Session Control Function).
Once the communication is established, the application network
function notifies the PCF about the new IP flow. The PCF function in
turn notifies the LMA about the needed QoS parameters identifying the
IP flow and QoS parameters. LMA sends an Update Notification message
[RFC7077] to the MAG with the Notification Reason value set to
QOS_SERVICE_REQUEST. On receiving the Update Notification message,
the MAG completes the PBU/PBA signaling for obtaining the new QoS
parameters via the QoS options (OC=MODIFY, SR-ID, QoS attributes,
etc.). The MAG provisions the newly obtained QoS parameters on the
access network to ensure the newly established IP flow gets its
requested network resources.
Upon termination of the established IP flow, the application function
again notifies the PCF function to remove the established QoS
parameters. The PCF notifies the LMA to withdraw the QoS resources
established for that voice flow. The LMA sends an Update
Notification message to the MAG with the "Notification Reason" value
set to "FORCE-REREGISTRATION". On receiving this Update Notification
Acknowledgement message, the MAG completes the PBU/PBA signaling for
removing the existing QoS rules (OC=DE-ALLOCATE, SR-ID). The MAG
then removes the QoS parameters from the corresponding IP flow and
releases the dedicated network resources on the access network.
Appendix B. Information When Implementing PMIP-Based QoS Support with
IEEE 802.11e
This section shows, as an example, the end-to-end QoS management with
a 802.11e-capable WLAN access link and a PMIP-based QoS support.
The 802.11e, or Wi-Fi Multimedia (WMM), specification provides
prioritization of packets for four types of traffic, or access
categories (ACs):
Voice (AC_VO): Very high-priority queue with minimum delay. Time-
sensitive data such as VoIP and streaming mode are automatically
sent to this queue.
Video (AC_VI): High-priority queue with low delay. Time-sensitive
video data is automatically sent to this queue.
Best effort (AC_BE): Medium-priority queue with medium throughput
and delay. Most traditional IP data is sent to this queue.
Background (AC_BK): Lowest-priority queue with high throughput.
Bulk data that requires maximum throughput but is not time-
sensitive (for example, FTP data) is sent to the queue.
The access point uses the 802.11e indicator to prioritize traffic on
the WLAN interface. On the wired side, the access point uses the
802.1p priority tag and DSCP. To allow consistent QoS management on
both wireless and wired interfaces, the access point relies on the
802.11e specification, which defines mapping between the 802.11e
access categories and the IEEE 802.1D priority (802.1p tag). The
end-to-end QoS architecture is depicted in Figure 13, and the 802.11e
/802.1D priority mapping is shown in the following table:
+-----------+------------------+
| 802.1e AC | 802.1D priority |
+-----------+------------------+
| AC_VO | 7,6 |
+-----------+------------------+
| AC_VI | 5,4 |
+-----------+------------------+
| AC_BE | 0,3 |
+-----------+------------------+
| AC_BK | 2,1 |
+-----------+------------------+
+=============+ +-----+
DSCP/802.1p | PDP |
mapping table +-----+
+=============+ PEP |
`._ +---+---+ |
`._ |WiFi AR| PMIPv6 +-----+
- + (MAG) +===============| LMA |
| WLC | tunnel +-----+
+-------+ PEP
|
==Video== 802.1p/DSCP
==Voice== |
== B.E.== +----+
+----+ |WLAN| PEP
| MN |----802.11e----| AP |
+----+ +----+
Figure 13: End-to-End QoS Management with 802.11e
When receiving a packet from the MN, the AP checks whether the frame
contains 802.11e markings in the L2 header. If not, the AP checks
the DSCP field. If the uplink packet contains the 802.11e marking,
the access point maps the access categories to the corresponding
802.1D priority as per the table above. If the frame does not
contain 802.11e marking, the access point examines the DSCP field.
If DSCP is present, the AP maps DSCP values to a 802.1p value (i.e.,
802.1D priority). This mapping is not standardized and may differ
between operators; a mapping example is given in the following table.
+-------------------+--------+------------+
| Type of traffic | 802.1p | DSCP value |
+-------------------+--------+------------+
| Network Control | 7 | 56 |
+-------------------+--------+------------+
| Voice | 6 | 46 (EF) |
+-------------------+--------+------------+
| Video | 5 | 34 (AF 41) |
+-------------------+--------+------------+
| Voice Control | 4 | 26 (AF 31) |
+-------------------+--------+------------+
| Background Gold | 2 | 18 (AF 21) |
+-------------------+--------+------------+
| Background Silver | 1 | 10 (AF 11) |
+-------------------+--------+------------+
| Best Effort | 0,3 | 0 (BE) |
+-------------------+--------+------------+
The access point prioritizes ingress traffic on the Ethernet port
based on the 802.1p tag or the DSCP value. If the 802.1p priority
tag is not present, the access point checks the DSCP/802.1p mapping
table. The next step is to map the 802.1p priority to the
appropriate egress queue. When 802.11e support is enabled on the
wireless link, the access point uses the IEEE standardized 802.1p/
802.11e correspondence table to map the traffic to the appropriate
hardware queues.
When the 802.11e-capable client sends traffic to the AP, it usually
marks packets with a DSCP value. In that case, the MAG/LMA can come
into play for QoS renegotiation and call flows depicted in Appendix A
apply. Sometimes, when communication is initiated on the WLAN
access, the application does not mark upstream packets. If the
uplink packet does not contain any QoS marking, the AP/MAG could
determine the DSCP field according to traffic selectors received from
the LMA. Figure 14 gives the call flow corresponding to that use
case and shows where QoS tags mapping does come into play. The main
steps are as follows:
(A): During the MN attachment process, the MAG fetches QoS
policies from the LMA. After this step, both the MAG and LMA are
provisioned with QoS policies.
(B): The MN starts a new IP communication without making IP
packets with DSCP tags. The MAG uses the traffic selector to
determine the DSCP value; it then marks the IP packet and forwards
within the PMIP tunnel.
(C): The LMA checks the DSCP value with respect to the traffic
selector. If the QoS policies are valid, the LMA forwards the
packet without renegotiating the QoS rules.
(D): When receiving a marked packet, the MAG, the AP, and the MN
use 802.11e (or WMM), 802.1p tags, and DSCP values to prioritize
the traffic.
+--+ +--+ +---+ +---+
|MN| |AP| |MAG| |LMA|
+--+ + -+ +---+ +---+
(A)|----attach-----|---------------->|-----------PBU---------->|
|<--------------|---------------- |<----PBA[QoS option]-----|
. . [QoS rules] [QoS rules]
(B). . . |
new session | | |
|----data[]---->|----data[]------>|-======data[DSCP]======->|
| | | |
(C)| | | Validate QoS rule
| | | |--->
| | |<======data[DSCP]========|<----
| | | |
| | mapping |
(D)| | DSCP/802.1p |
| |<----data--------| |
| | [802.1p/DSCP] | |
| | | |
| mapping | |
| 802.1p/802.11e | |
|<--data[WMM]---| | |
| | | |
|---data[WMM]-->|------data------>|=======data[DSCP]=======>|--->
| | [802.1p/DSCP] | |
| | | |
Figure 14: Prioritization of a Flow Created on the WLAN Access
Appendix C. Information When Implementing with a Broadband Network
Gateway
This section shows an example of QoS interworking between the PMIPv6
domain and the broadband access. The Broadband Network Gateway (BNG)
or Broadband Remote Access Server (BRAS) has the MAG function, and
the CPE (Customer Premise Equipment) or Residential Gateway (RG) is
connected via the broadband access network. The MN is attached to
the RG via, e.g., Wi-Fi AP in the broadband home network. In the
segment of the broadband access network, the BNG and RG are the
Policy Enforcement Point (PEP) for the downlink and uplink traffic,
respectively. The QoS information is downloaded from the LMA to the
BNG via the PMIPv6 with the QoS option defined in this document.
Based on the received QoS parameters (e.g., DSCP values), the
broadband access network and the RG provide appropriate QoS treatment
to the downlink and uplink traffic to/from the MN.
+-----+
| PDP |
+-----+
PEP |
+-------+ |
| BNG/ | PMIPv6 +-----+
| BRAS +===============| LMA |
| (MAG) | tunnel +-----+
+-------+ PEP
Broadband ( | )
Access ( DSCP )
Network ( | )
+-----+
+----+ | CPE | PEP
| MN |-------------| /RG |
+----+ Broadband +-----+
Home Network
Figure 15: End-to-End QoS Management with the Broadband Access
Network
In the segment of the broadband access network, QoS mapping between
3GPP QCI values and DSCP described in Section 6.2 is applied. In the
segment of the broadband home network, if the MN is attached to the
RG via Wi-Fi, the same QoS mapping as described in Appendix B can be
applied.
Authors' Addresses
Marco Liebsch
NEC
Kurfuersten-Anlage 36
Heidelberg D-69115
Germany
EMail: liebsch@neclab.eu
Pierrick Seite
Orange
4, rue du Clos Courtel, BP 91226
Cesson-Sevigne 35512
France
EMail: pierrick.seite@orange.com
Hidetoshi Yokota
KDDI Lab
2-1-15 Ohara
Saitama, Fujimino 356-8502
Japan
EMail: yokota@kddilabs.jp
Jouni Korhonen
Broadcom Communications
Porkkalankatu 24
Helsinki FIN-00180
Finland
EMail: jouni.nospam@gmail.com
Sri Gundavelli
Cisco
170 West Tasman Drive
San Jose, CA 95134
USA
EMail: sgundave@cisco.com