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IETF RFC 5777
Traffic Classification and Quality of Service (QoS) Attributes for Diameter
Last modified on Friday, February 12th, 2010
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Internet Engineering Task Force (IETF) J. Korhonen
Request for Comments: 5777 H. Tschofenig
Category: Standards Track Nokia Siemens Networks
ISSN: 2070-1721 M. Arumaithurai
University of Goettingen
M. Jones, Ed.
A. Lior
Bridgewater Systems
February 2010
Traffic Classification and Quality of Service (QoS)
Attributes for Diameter
Abstract
This document defines a number of Diameter attribute-value pairs
(AVPs) for traffic classification with actions for filtering and
Quality of Service (QoS) treatment. These AVPs can be used in
existing and future Diameter applications where permitted by the
Augmented Backus-Naur Form (ABNF) specification of the respective
Diameter command extension policy.
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/RFC 5777.
Copyright Notice
Copyright (c) 2010 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
Korhonen, et al. Standards Track PAGE 1
RFC 5777 QoS Attributes for Diameter February 2010
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.
This document may contain material from IETF Documents or IETF
Contributions published or made publicly available before November
10, 2008. The person(s) controlling the copyright in some of this
material may not have granted the IETF Trust the right to allow
modifications of such material outside the IETF Standards Process.
Without obtaining an adequate license from the person(s) controlling
the copyright in such materials, this document may not be modified
outside the IETF Standards Process, and derivative works of it may
not be created outside the IETF Standards Process, except to format
it for publication as an RFC or to translate it into languages other
than English.
Table of Contents
1. Introduction ....................................................3
2. Terminology .....................................................4
3. Rule Sets and Rules .............................................4
3.1. QoS-Resources AVP ..........................................5
3.2. Filter-Rule AVP ............................................5
3.3. Filter-Rule-Precedence AVP .................................6
4. Conditions ......................................................6
4.1. Traffic Classifiers ........................................6
4.1.1. Classifier AVP ......................................8
4.1.2. Classifier-ID AVP ...................................9
4.1.3. Protocol AVP ........................................9
4.1.4. Direction AVP .......................................9
4.1.5. From-Spec AVP .......................................9
4.1.6. To-Spec AVP ........................................10
4.1.7. Source and Destination AVPs ........................11
4.1.8. Header Option AVPs .................................15
4.2. Time Of Day AVPs ..........................................22
4.2.1. Time-Of-Day-Condition AVP ..........................22
4.2.2. Time-Of-Day-Start AVP ..............................23
4.2.3. Time-Of-Day-End AVP ................................23
4.2.4. Day-Of-Week-Mask AVP ...............................23
4.2.5. Day-Of-Month-Mask AVP ..............................24
4.2.6. Month-Of-Year-Mask AVP .............................24
4.2.7. Absolute-Start-Time AVP ............................25
4.2.8. Absolute-Start-Fractional-Seconds AVP ..............25
4.2.9. Absolute-End-Time AVP ..............................25
4.2.10. Absolute-End-Fractional-Seconds AVP ...............25
4.2.11. Timezone-Flag AVP .................................25
4.2.12. Timezone-Offset AVP ...............................26
5. Actions ........................................................26
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RFC 5777 QoS Attributes for Diameter February 2010
5.1. Treatment-Action AVP ......................................26
5.2. QoS-Profile-Id AVP ........................................27
5.3. QoS-Profile-Template AVP ..................................27
5.4. QoS-Semantics .............................................28
5.5. QoS-Parameters AVP ........................................29
5.6. Excess-Treatment AVP ......................................29
6. QoS Capability Indication ......................................29
7. Examples .......................................................30
7.1. Diameter EAP with QoS Information .........................30
7.2. Diameter NASREQ with QoS Information ......................32
7.3. QoS Authorization .........................................33
7.4. Diameter Server Initiated Re-Authorization of QoS .........33
7.5. Diameter Credit Control (CC) with QoS Information .........34
7.6. Classifier Examples .......................................35
7.7. QoS Parameter Examples ....................................37
8. Acknowledgments ................................................37
9. Contributors ...................................................37
10. IANA Considerations ...........................................38
10.1. AVP Codes ................................................38
10.2. QoS-Semantics IANA Registry ..............................39
10.3. Action ...................................................40
11. Security Considerations .......................................40
12. References ....................................................40
12.1. Normative References .....................................40
12.2. Informative References ...................................41
Appendix A. MAC and EUI64 Address Mask Usage Considerations ......42
1. Introduction
This document defines a number of Diameter attribute-value pairs
(AVPs) for traffic classification with actions for filtering and
Quality of Service (QoS) treatment. These AVPs can be used in
existing and future Diameter applications where permitted by the
Augmented Backus-Naur Form (ABNF) specification of the respective
Diameter command extension policy.
The work on Quality of Service treatment and filtering via Diameter
dates back to the base protocol described in RFC 3588 [RFC 3588]. The
filtering and QoS functionality was provided by the IPFilterRule AVP
and the QoSFilterRule AVP. Both AVPs relied on syntax based on the
FreeBSD ipfw tool for traffic classification. The functionality of
the QoSFilterRule AVP was underspecified in RFC 3588 [RFC 3588] and
was later updated by RFC 4005 [RFC 4005].
As part of the work on updating RFC 3588, the functionality of the
IPFilterRule and the QoSFilterRule was revised by the functionality
offered by this document with the goals of a uniform and extensible
traffic classification mechanism in a native Diameter syntax (instead
Korhonen, et al. Standards Track PAGE 3
RFC 5777 QoS Attributes for Diameter February 2010
of the free text previously used). Additionally, an extensible set
of actions is provided that offers the ability for filtering and for
QoS treatment, whereby the QoS functionality was extended to meet the
needs of today's networking environments.
The QoS-Resources AVP represents a complete rule set with each rule
represented by a Filter-Rule AVP. Each rule consists of information
for handling conflict resolution, a conditions part and the
corresponding actions to be performed if the conditions are
satisfied. The AVPs responsible for expressing a condition are
defined in Section 4. The capability to match all or a subset of the
data traffic is provided. This includes the ability to match on
Ethernet specific attributes, which was not possible with the QoS-
Filter-Rule AVP. Service differentiation may be based on Ethernet
priority bits, a single layer of VLAN-IDs or stacked VLAN-IDs,
Logical Link Control (LLC) attributes, MAC addresses, or any
combination thereof. The header fields used for Ethernet
classification are defined in the IEEE802 series of specifications:
[IEEE802.2], [IEEE802.1ad], [IEEE802.1Q], and [IEEE802.1D].
Additionally, time-based conditions can be expressed based on the
functionality offered by the attributes in Section 4.2.
The action part of a rule contains the type of traffic treatment and
further description regarding QoS-related actions.
The QoS policy rules are defined as Diameter encoded attribute-value
pairs (AVPs) described using a modified version of the Augmented
Backus-Naur Form (ABNF) (see [RFC 3588]). The AVP datatypes are also
taken from [RFC 3588].
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC 2119].
3. Rule Sets and Rules
As mentioned in the introduction, the top-level element is the QoS-
Resources AVP that encapsulates one or more Filter-Rule AVPs.
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3.1. QoS-Resources AVP
The QoS-Resources AVP (AVP Code 508) is of type Grouped and contains
a list of filter policy rules.
QoS-Resources ::= < AVP Header: 508 >
1*{ Filter-Rule }
* [ AVP ]
3.2. Filter-Rule AVP
The Filter-Rule AVP (AVP Code 509) is of type Grouped and defines a
specific condition and action combination.
Filter-Rule ::= < AVP Header: 509 >
[ Filter-Rule-Precedence ]
; Condition part of a Rule
; ------------------------
[ Classifier ]
* [ Time-Of-Day-Condition ]
; Action and Meta-Data
; --------------------
[ Treatment-Action ]
; Info about QoS related Actions
; ------------------------------
[ QoS-Semantics ]
[ QoS-Profile-Template ]
[ QoS-Parameters ]
[ Excess-Treatment ]
; Extension Point
; ---------------
* [ AVP ]
If the QoS-Profile-Template AVP is not included in the Filter-Rule
AVP and the Treatment-Action AVP is set to 'shape' or 'mark' then the
default setting is assumed, namely, a setting of the Vendor-Id AVP to
0 (for IETF) and the QoS-Profile-Id AVP to zero (0) (for the profile
defined in [RFC 5624]). Note that the content of the QoS-Parameters
are defined in the respective specification defining the QoS
parameters. When the Vendor-Id AVP is set to 0 (for IETF) and the
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RFC 5777 QoS Attributes for Diameter February 2010
QoS-Profile-Id AVP is set to zero (0), then the AVPs included in the
QoS-Parameters AVP are the AVPs defined in [RFC 5624].
3.3. Filter-Rule-Precedence AVP
The Filter-Rule-Precedence AVP (AVP Code 510) is of type Unsigned32
and specifies the execution order of the rules expressed in the QoS-
Resources AVP. The lower the numerical value of Filter-Rule-
Precedence AVP, the higher the rule precedence. Rules with equal
precedence MAY be executed in parallel if supported by the Resource
Management Function. If the Filter-Rule-Precedence AVP is absent
from the Filter-Rule AVP, the rules SHOULD be executed in the order
in which they appear in the QoS-Resources AVP.
4. Conditions
This section describes the condition part of a rule. Two condition
types are introduced by this document: packet classification
conditions represented by the Classifier AVP and time of day
conditions represented by the Time-Of-Day-Condition AVP.
If more than one instance of the Time-Of-Day-Condition AVP is present
in the Filter-Rule AVP, the current time at rule evaluation MUST be
within at least one of the time windows specified in one of the Time-
Of-Day-Condition AVPs.
When the Time-Of-Day-Condition AVP and Classifier AVP are present in
the same Filter-Rule AVP, both the time of day and packet
classification conditions MUST match for the traffic treatment action
to be applied.
4.1. Traffic Classifiers
Classifiers are used in many applications to specify how to select a
subset of data packets for subsequent treatment as indicated in the
action part of a rule. For example, in a QoS application, if a
packet matches a classifier then that packet will be treated in
accordance with a QoS specification associated with that classifier.
Figure 1 shows a typical deployment.
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+-----------+
+-----------+|
+--------+ +-------------+ +------------+||
| | IN | | | |||
| +--------->| +------------->| |||
|Managed | | Classifying | | Unmanaged |||
|Terminal| OUT | Entity | | Terminal |||
| |<---------+ |<-------------+ ||+
| | | | | |+
+--------+ +-------------+ +------------+
^
| Classifiers
|
+------+------+
| |
| AAA |
| |
+-------------+
Figure 1: Example of a Classifier Architecture
The managed terminal, the terminal for which the classifiers are
being specified, is located on the left of the Classifying Entity.
The unmanaged terminals, the terminals that receive packets from the
managed terminal or send packets to the managed terminal, are located
to the right side of the Classifying Entity.
The Classifying Entity is responsible for classifying packets that
are incoming (IN) from the managed terminal or packets outgoing (OUT)
to the managed terminal.
A classifier consists of a group of attributes that specify how to
match a packet. Each set of attributes expresses values about
aspects of the packet -- typically the packet header. Different
protocols therefore would use different attributes.
In general, a classifier consists of the following:
Identifier:
The identifier uniquely identifies this classifier and may be used
to reference the classifier from another structure.
From:
Specifies the rule for matching the protocol-specific source
address(es) part of the packet.
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To:
Specifies the rule for matching the protocol-specific destination
address(es) part of the packet.
Protocol:
Specifies the matching protocol of the packet.
Direction:
Specifies whether the classifier is to apply to packets flowing
from the managed terminal (IN) or to packets flowing to the
managed terminal (OUT) or to packets flowing in both directions.
Options:
Attributes or properties associated with each protocol or layer,
or various values specific to the header of the protocol or layer.
Options allow matching on those values.
Each protocol type will have a specific set of attributes that can be
used to specify a classifier for that protocol. These attributes
will be grouped under a grouped AVP called a Classifier AVP.
4.1.1. Classifier AVP
The Classifier AVP (AVP Code 511) is a grouped AVP that consists of a
set of attributes that specify how to match a packet.
Classifier ::= < AVP Header: 511 >
{ Classifier-ID }
[ Protocol ]
[ Direction ]
* [ From-Spec ]
* [ To-Spec ]
* [ Diffserv-Code-Point ]
[ Fragmentation-Flag ]
* [ IP-Option ]
* [ TCP-Option ]
[ TCP-Flags ]
* [ ICMP-Type ]
* [ ETH-Option ]
* [ AVP ]
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4.1.2. Classifier-ID AVP
The Classifier-ID AVP (AVP Code 512) is of type OctetString and
uniquely identifies the classifier. Each application will define the
uniqueness scope of this identifier, e.g., unique per terminal or
globally unique. Exactly one Classifier-ID AVP MUST be contained
within a Classifier AVP.
4.1.3. Protocol AVP
The Protocol AVP (AVP Code 513) is of type Enumerated and specifies
the protocol being matched. The attributes included in the
Classifier AVP MUST be consistent with the value of the Protocol AVP.
Exactly zero or one Protocol AVP may be contained within a Classifier
AVP. If the Protocol AVP is omitted from the classifier, then
comparison of the protocol of the packet is irrelevant. The values
for this AVP are managed by IANA under the Protocol Numbers registry
as defined in [RFC 2780].
4.1.4. Direction AVP
The Direction AVP (AVP Code 514) is of type Enumerated and specifies
in which direction to apply the classifier. The values of the
enumeration are "IN","OUT","BOTH". In the "IN" and "BOTH"
directions, the From-Spec refers to the address of the managed
terminal and the To-Spec refers to the unmanaged terminal. In the
"OUT" direction, the From-Spec refers to the unmanaged terminal
whereas the To-Spec refers to the managed terminal. If the Direction
AVP is omitted, the classifier matches packets flowing in both
directions.
Value | Name and Semantic
------+--------------------------------------------------
0 | IN - The classifier applies to flows from the
| managed terminal.
1 | OUT - The classifier applies to flows to the
| managed terminal.
2 | BOTH - The classifier applies to flows both to
| and from the managed terminal.
4.1.5. From-Spec AVP
The From-Spec AVP (AVP Code 515) is a grouped AVP that specifies the
Source Specification used to match the packet. Zero or more of these
AVPs may appear in the classifier. If this AVP is absent from the
classifier, then all packets are matched regardless of the source
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address. If more than one instance of this AVP appears in the
classifier, then the source of the packet can match any From-Spec
AVP. The contents of this AVP are protocol specific.
If one instance (or multiple instances) of the IP address AVP (IP-
Address, IP-Address-Range, IP-Address-Mask, Use-Assigned-Address)
appears in the From-Spec AVP, then the source IP address of the
packet MUST match one of the addresses represented by these AVPs.
If more than one instance of the layer 2 address AVPs (MAC-Address,
MAC-Address-Mask, EUI64-Address, EUI64-Address-Mask) appears in the
From-Spec, then the source layer 2 address of the packet MUST match
one of the addresses represented in these AVPs.
If more than one instance of the port AVPs (Port, Port-Range) appears
in the From-Spec AVP, then the source port number MUST match one of
the port numbers represented in these AVPs.
If the IP address, MAC address, and port AVPs appear in the same
From-Spec AVP, then the source packet MUST match all the
specifications, i.e., match the IP address AND MAC address AND port
number.
From-Spec ::= < AVP Header: 515 >
* [ IP-Address ]
* [ IP-Address-Range ]
* [ IP-Address-Mask ]
* [ MAC-Address ]
* [ MAC-Address-Mask]
* [ EUI64-Address ]
* [ EUI64-Address-Mask]
* [ Port ]
* [ Port-Range ]
[ Negated ]
[ Use-Assigned-Address ]
* [ AVP ]
4.1.6. To-Spec AVP
The To-Spec AVP (AVP Code 516) is a grouped AVP that specifies the
Destination Specification used to match the packet. Zero or more of
these AVPs may appear in the classifier. If this AVP is absent from
the classifier, then all packets are matched regardless of the
destination address. If more than one instance of this AVP appears
in the classifier, then the destination of the packet can match any
To-Spec AVP. The contents of this AVP are protocol specific.
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If one instance (or multiple instances) of the IP address AVP (IP-
Address, IP-Address-Range, IP-Address-Mask, Use-Assigned-Address)
appears in the To-Spec AVP, then the destination IP address of the
packet MUST match one of the addresses represented by these AVPs.
If more than one instance of the layer 2 address AVPs (MAC-Address,
MAC-Address-Mask, EUI64-Address, EUI64-Address-Mask) appears in the
To-Spec, then the destination layer 2 address of the packet MUST
match one of the addresses represented in these AVPs.
If more than one instance of the port AVPs (Port, Port-Range) appears
in the To-Spec AVP, then the destination port number MUST match one
of the port numbers represented in these AVPs.
If the IP address, MAC address, and port AVPs appear in the same To-
Spec AVP, then the destination packet MUST match all the
specifications, i.e., match the IP address AND MAC address AND port
number.
To-Spec ::= < AVP Header: 516 >
* [ IP-Address ]
* [ IP-Address-Range ]
* [ IP-Address-Mask ]
* [ MAC-Address ]
* [ MAC-Address-Mask]
* [ EUI64-Address ]
* [ EUI64-Address-Mask]
* [ Port ]
* [ Port-Range ]
[ Negated ]
[ Use-Assigned-Address ]
* [ AVP ]
4.1.7. Source and Destination AVPs
For packet classification, the contents of the From-Spec and To-Spec
can contain the AVPs listed in the subsections below.
4.1.7.1. Negated AVP
The Negated AVP (AVP Code 517) is of type Enumerated containing the
values of True or False. Exactly zero or one of these AVPs may
appear in the From-Spec or To-Spec AVP.
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When set to True, the meaning of the match is inverted and the
classifier will match addresses other than those specified by the
From-Spec or To-Spec AVP. When set to False, or when the Negated AVP
is not present, the classifier will match the addresses specified by
the From-Spec or To-Spec AVP.
Note that the negation does not impact the port comparisons.
Value | Name
------+--------
0 | False
1 | True
4.1.7.2. IP-Address AVP
The IP-Address AVP (AVP Code 518) is of type Address and specifies a
single IP address (IPv4 or IPv6) to match.
4.1.7.3. IP-Address-Range AVP
The IP-Address-Range AVP (AVP Code 519) is of type Grouped and
specifies an inclusive IP address range.
IP-Address-Range ::= < AVP Header: 519 >
[ IP-Address-Start ]
[ IP-Address-End ]
* [ AVP ]
If the IP-Address-Start AVP is not included, then the address range
starts from the first valid IP address up to and including the
specified IP-Address-End address.
If the IP-Address-End AVP is not included, then the address range
starts at the address specified by the IP-Address-Start AVP and
includes all the remaining valid IP addresses.
For the IP-Address-Range AVP to be valid, the IP-Address-Start AVP
MUST contain a value that is less than that of the IP-Address-End
AVP.
4.1.7.4. IP-Address-Start AVP
The IP-Address-Start AVP (AVP Code 520) is of type Address and
specifies the first IP address (IPv4 or IPv6) of an IP address range.
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4.1.7.5. IP-Address-End AVP
The IP-Address-End AVP (AVP Code 521) is of type Address and
specifies the last IP address (IPv4 or IPv6) of an address range.
4.1.7.6. IP-Address-Mask AVP
The IP-Address-Mask AVP (AVP Code 522) is of type Grouped and
specifies an IP address range using a base IP address and the bit-
width of the mask. For example, a range expressed as 192.0.2.0/24
will match all IP addresses from 192.0.2.0 up to and including
192.0.2.255. The bit-width MUST be valid for the type of IP address.
IP-Address-Mask ::= < AVP Header: 522 >
{ IP-Address }
{ IP-Bit-Mask-Width }
* [ AVP ]
4.1.7.7. IP-Mask-Bit-Mask-Width AVP
The IP-Bit-Mask-Width AVP (AVP Code 523) is of type Unsigned32. The
value specifies the width of an IP address bit mask.
4.1.7.8. MAC-Address AVP
The MAC-Address AVP (AVP Code 524) is of type OctetString and
specifies a single layer 2 address in MAC-48 format. The value is a
6-octet encoding of the address as it would appear in the frame
header.
4.1.7.9. MAC-Address-Mask AVP
The MAC-Address-Mask AVP (AVP Code 525) is of type Grouped and
specifies a set of MAC addresses using a bit mask to indicate the
bits of the MAC addresses that must fit to the specified MAC address
attribute. For example, a MAC-Address-Mask with the MAC-Address as
00-10-A4-23-00-00 and with a MAC-Address-Mask-Pattern of FF-FF-FF-FF-
00-00 will match all MAC addresses from 00-10-A4-23-00-00 up to and
including 00-10-A4-23-FF-FF.
Appendix A describes the considerations that should be given to the
use of MAC address masks in constructing classifiers.
MAC-Address-Mask ::= < AVP Header: 525 >
{ MAC-Address }
{ MAC-Address-Mask-Pattern }
* [ AVP ]
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4.1.7.10. MAC-Address-Mask-Pattern AVP
The MAC-Address-Mask-Pattern AVP (AVP Code 526) is of type
OctetString. The value is 6 octets specifying the bit positions of a
MAC address that are taken for matching.
4.1.7.11. EUI64-Address AVP
The EUI64-Address AVP (AVP Code 527) is of type OctetString and
specifies a single layer 2 address in EUI-64 format. The value is an
8-octet encoding of the address as it would appear in the frame
header.
4.1.7.12. EUI64-Address-Mask AVP
The EUI64-Address-Mask AVP (AVP Code 528) is of type Grouped and
specifies a set of EUI64 addresses using a bit mask to indicate the
bits of the EUI64 addresses that must fit to the specified EUI64
address attribute. For example, a EUI64-Address-Mask with the EUI64-
Address as 00-10-A4-FF-FE-23-00-00 and with a EUI64-Address-Mask-
Pattern of FF-FF-FF-FF-FF-FF-00-00 will match all EUI64 addresses
from 00-10-A4-FF-FE-23-00-00 up to and including 00-10-A4-FF-FE-23-
FF-FF.
Appendix A describes the considerations that should be given to the
use of EUI64 address masks in constructing classifiers.
EUI64-Address-Mask ::= < AVP Header: 528 >
{ EUI64-Address }
{ EUI64-Address-Mask-Pattern }
* [ AVP ]
4.1.7.13. EUI64-Address-Mask-Pattern AVP
The EUI64-Address-Mask-Pattern AVP (AVP Code 529) is of type
OctetString. The value is 8 octets specifying the bit positions of a
EUI64 address that are taken for matching.
4.1.7.14. Port AVP
The Port AVP (AVP Code 530) is of type Integer32 in the range of 0 to
65535 and specifies port numbers to match. The type of port is
indicated by the value of the Protocol AVP; i.e., if Protocol AVP
value is 6 (TCP), then the Port AVP represents a TCP port.
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4.1.7.15. Port-Range AVP
The Port-Range AVP (AVP Code 531) is of type Grouped and specifies an
inclusive range of ports. The type of the ports is indicated by the
value of the Protocol AVP; i.e., if Protocol AVP value is 6 (TCP),
then the Port-Range AVP represents an inclusive range of TCP ports.
Port-Range ::= < AVP Header: 531 >
[ Port-Start ]
[ Port-End ]
* [ AVP ]
If the Port-Start AVP is omitted, then port 0 is assumed. If the
Port-End AVP is omitted, then port 65535 is assumed.
4.1.7.16. Port-Start AVP
The Port-Start AVP (AVP Code 532) is of type Integer32 and specifies
the first port number of an IP port range.
4.1.7.17. Port-End AVP
The Port-End AVP (AVP Code 533) is of type Integer32 and specifies
the last port number of an IP port range.
4.1.7.18. Use-Assigned-Address AVP
In some scenarios, the AAA does not know the IP address assigned to
the managed terminal at the time that the classifier is sent to the
Classifying Entity. The Use-Assigned-Address AVP (AVP Code 534) is
of type Enumerated containing the values of True or False. When
present and set to True, it represents the IP address assigned to the
managed terminal.
Value | Name
------+--------
0 | False
1 | True
4.1.8. Header Option AVPs
The Classifier AVP may contain one or more of the following AVPs to
match on the various possible IP, TCP, or ICMP header options.
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4.1.8.1. Diffserv-Code-Point AVP
The Diffserv-Code-Point AVP (AVP Code 535) is of type Enumerated and
specifies the Differentiated Services Field Codepoints to match in
the IP header. The values are managed by IANA under the
Differentiated Services Field Codepoints registry as defined in
[RFC 2474].
4.1.8.2. Fragmentation-Flag AVP
The Fragmentation-Flag AVP (AVP Code 536) is of type Enumerated and
specifies the packet fragmentation flags to match in the IP header.
Value | Name and Semantic
------+------------------------------------------------------------
0 | Don't Fragment (DF)
1 | More Fragments (MF)
4.1.8.3. IP-Option AVP
The IP-Option AVP (AVP Code 537) is of type Grouped and specifies an
IP header option that must be matched.
IP-Option ::= < AVP Header: 537 >
{ IP-Option-Type }
* [ IP-Option-Value ]
[ Negated ]
* [ AVP ]
If one or more IP-Option-Value AVPs are present, one of the values
MUST match the value in the IP header option. If the IP-Option-Value
AVP is absent, the option type MUST be present in the IP header but
the value is wild carded.
The Negated AVP is used in conjunction with the IP-Option-Value AVPs
to specify IP header options that do not match specific values. The
Negated AVP is used without the IP-Option-Value AVP to specify IP
headers that do not contain the option type.
4.1.8.4. IP-Option-Type AVP
The IP-Option-Type AVP (AVP Code 538) is of type Enumerated and the
values are managed by IANA under the IP Option Numbers registry as
defined in [RFC 2780].
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4.1.8.5. IP-Option-Value AVP
The IP-Option-Value AVP (AVP Code 539) is of type OctetString and
contains the option value that must be matched.
4.1.8.6. TCP-Option AVP
The TCP-Option AVP (AVP Code 540) is of type Grouped and specifies a
TCP header option that must be matched.
TCP-Option ::= < AVP Header: 540 >
{ TCP-Option-Type }
* [ TCP-Option-Value ]
[ Negated ]
* [ AVP ]
If one or more TCP-Option-Value AVPs are present, one of the values
MUST match the value in the TCP header option. If the TCP-Option-
Value AVP is absent, the option type MUST be present in the TCP
header but the value is wild carded.
The Negated AVP is used in conjunction that the TCP-Option-Value AVPs
to specify TCP header options that do not match specific values. The
Negated AVP is used without the TCP-Option-Value AVP to specify TCP
headers that do not contain the option type.
4.1.8.7. TCP-Option-Type AVP
The TCP-Option-Type AVP (AVP Code 541) is of type Enumerated and the
values are managed by IANA under the TCP Option Numbers registry as
defined in [RFC 2780].
4.1.8.8. TCP-Option-Value AVP
The TCP-Option-Value AVP (AVP Code 542) is of type OctetString and
contains the option value that must be matched.
4.1.8.9. TCP-Flags AVP
The TCP-Flags AVP (AVP Code 543) is of type Grouped and specifies a
set of TCP control flags that must be matched.
TCP-Flags ::= < AVP Header: 543 >
{ TCP-Flag-Type }
[ Negated ]
* [ AVP ]
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If the Negated AVP is not present or present but set to False, the
TCP-Flag-Type AVP specifies which flags MUST be set. If the Negated
AVP is set to True, the TCP-Flag-Type AVP specifies which flags MUST
be cleared.
4.1.8.10. TCP-Flag-Type AVP
The TCP-Flag-Type AVP (AVP Code 544) is of type Unsigned32 and
specifies the TCP control flag types that must be matched. The first
16 bits match the TCP header format defined in [RFC 3168], and the
subsequent 16 bits are unused. Within the first 16 bits, bits 0 to 3
are unused and bits 4 to 15 are managed by IANA under the TCP Header
Flag registry as defined in [RFC 3168].
4.1.8.11. ICMP-Type
The ICMP-Type AVP (AVP Code 545) is of type Grouped and specifies an
ICMP message type that must be matched.
ICMP-Type ::= < AVP Header: 545 >
{ ICMP-Type-Number }
* [ ICMP-Code ]
[ Negated ]
* [ AVP ]
If the ICMP-Code AVP is present, the value MUST match that in the
ICMP header. If the ICMP-Code AVP is absent, the ICMP type MUST be
present in the ICMP header but the code is wild carded.
The Negated AVP is used in conjunction with the ICMP-Code AVPs to
specify ICMP codes that do not match specific values. The Negated
AVP is used without the ICMP-Code AVP to specify ICMP headers that do
not contain the ICMP type. As such, the Negated AVP feature applies
to ICMP-Code AVP if the ICMP-Code AVP is present. If the ICMP-Code
AVP is absent, the Negated AVP feature applies to the ICMP-Type-
Number.
4.1.8.12. ICMP-Type-Number AVP
The ICMP-Type-Number AVP (AVP Code 546) is of type Enumerated and the
values are managed by IANA under the ICMP Type Numbers registry as
defined in [RFC 2780].
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4.1.8.13. ICMP-Code AVP
The ICMP-Code AVP (AVP Code 547) is of type Enumerated and the values
are managed by IANA under the ICMP Type Numbers registry as defined
in [RFC 2780].
4.1.8.14. ETH-Option AVP
The ETH-Option AVP (AVP Code 548) is of type Grouped and specifies
Ethernet specific attributes.
ETH-Option ::= < AVP Header: 548 >
{ ETH-Proto-Type }
* [ VLAN-ID-Range ]
* [ User-Priority-Range ]
* [ AVP ]
4.1.8.15. ETH-Proto-Type AVP
The Eth-Proto-Type AVP (AVP Code 549) is of type Grouped and
specifies the encapsulated protocol type. ETH-Ether-Type and ETH-SAP
are mutually exclusive.
ETH-Proto-Type ::= < AVP Header: 549 >
* [ ETH-Ether-Type ]
* [ ETH-SAP ]
* [ AVP ]
4.1.8.16. ETH-Ether-Type AVP
The ETH-Ether-Type AVP (AVP Code 550) is of type OctetString. The
value is a double octet that contains the value of the Ethertype
field in the packet to match. This AVP MAY be present in the case of
Digital, Intel, and Xerox (DIX) or if the Subnetwork Access Protocol
(SNAP) is present at 802.2, but the ETH-SAP AVP MUST NOT be present
in this case.
4.1.8.17. ETH-SAP AVP
The ETH-SAP AVP (AVP Code 551) is of type OctetString. The value is
a double octet representing the 802.2 SAP as specified in
[IEEE802.2]. The first octet contains the Destination Service Access
Point (DSAP) and the second the Source Service Access Point (SSAP).
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4.1.8.18. VLAN-ID-Range AVP
The VLAN-ID-Range AVP (AVP Code 552) is of type Grouped and specifies
the VLAN range to match. VLAN identities are specified either by a
single VLAN-ID according to [IEEE802.1Q] or by a combination of
Customer and Service VLAN-IDs according to [IEEE802.1ad].
The single VLAN-ID is represented by the C-VID-Start and C-VID-End
AVPs, and the S-VID-Start and S-VID-End AVPs SHALL be omitted in this
case. If the VLAN-ID-Range AVP is omitted from the classifier, then
comparison of the VLAN identity of the packet is irrelevant.
VLAN-ID-Range ::= < AVP Header: 552 >
[ S-VID-Start ]
[ S-VID-End ]
[ C-VID-Start ]
[ C-VID-End ]
* [ AVP ]
The following is the list of possible combinations of the S-VID-Start
and S-VID-End AVPs and their inference:
o If S-VID-Start AVP is present but the S-VID-End AVP is absent, the
S-VID-Start AVP value MUST equal the value of the IEEE 802.1ad
S-VID bits specified in [IEEE802.1ad] for a successful match.
o If S-VID-Start AVP is absent but the S-VID-End AVP is present, the
S-VID-End AVP value MUST equal the value of the IEEE 802.1ad S-VID
bits for a successful match.
o If both S-VID-Start and S-VID-End AVPs are present and their
values are equal, the S-VID-Start AVP value MUST equal the value
of the IEEE 802.1ad S-VID bits for a successful match.
o If both S-VID-Start and S-VID-End AVPs are present and the value
of S-VID-End AVP is greater than the value of the S-VID-Start AVP,
the value of the IEEE 802.1ad S-VID bits MUST be greater than or
equal to the S-VID-Start AVP value and less than or equal to the
S-VID-End AVP value for a successful match. If the S-VID-Start
and S-VID-End AVPs are specified, then Ethernet packets without
IEEE 802.1ad encapsulation MUST NOT match this classifier.
o If the S-VID-Start and S-VID-End AVPs are omitted, then existence
of IEEE802.1ad encapsulation or comparison of the IEEE 802.1ad
S-VID bits is irrelevant for this classifier.
The following is the list of possible combinations of the C-VID-Start
and C-VID-End AVPs and their inference:
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o If C-VID-Start AVP is present but the C-VID-End AVP is absent, the
C-VID-Start AVP value MUST equal the value of the IEEE 802.1ad
C-VID bits specified in [IEEE802.1ad] or the IEEE 802.1Q VLAN-ID
bits specified in [IEEE802.1Q] for a successful match.
o If C-VID-Start AVP is absent but the C-VID-End AVP is present, the
C-VID-End AVP value MUST equal the value of the IEEE 802.1ad C-VID
bits or the IEEE 802.1Q VLAN-ID bits for a successful match.
o If both C-VID-Start and C-VID-End AVPs are present and their
values are equal, the C-VID-Start AVP value MUST equal the value
of the IEEE 802.1ad C-VID bits or the IEEE 802.1Q VLAN-ID bits for
a successful match.
o If both C-VID-Start and C-VID-End AVPs are present and the value
of C-VID-End AVP is greater than the value of the C-VID-Start AVP,
the value of the IEEE 802.1ad C-VID bits or the IEEE 802.1Q
VLAN-ID bits MUST be greater than or equal to the C-VID-Start AVP
value and less than or equal to the C-VID-End AVP value for a
successful match. If the C-VID-Start and C-VID-End AVPs are
specified, then Ethernet packets without IEEE 802.1ad or IEEE
802.1Q encapsulation MUST NOT match this classifier.
o If the C-VID-Start and C-VID-End AVPs are omitted, the comparison
of the IEEE 802.1ad C-VID bits or IEEE 802.1Q VLAN-ID bits for
this classifier is irrelevant.
4.1.8.19. S-VID-Start AVP
The S-VID-Start AVP (AVP Code 553) is of type Unsigned32. The value
MUST be in the range from 0 to 4095. The value of this AVP specifies
the start value of the range of S-VID VLAN-IDs to be matched.
4.1.8.20. S-VID-End AVP
The S-VID-End AVP (AVP Code 554) is of type Unsigned32. The value
MUST be in the range from 0 to 4095. The value of this AVP specifies
the end value of the range of S-VID VLAN-IDs to be matched.
4.1.8.21. C-VID-Start AVP
The C-VID-Start AVP (AVP Code 555) is of type Unsigned32. The value
MUST be in the range from 0 to 4095. The value of this AVP specifies
the start value of the range of C-VID VLAN-IDs to be matched.
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4.1.8.22. C-VID-End AVP
The C-VID-End AVP (AVP Code 556) is of type Unsigned32. The value
MUST be in the range from 0 to 4095. The value of this AVP specifies
the end value of the range of C-VID VLAN-IDs to be matched.
4.1.8.23. User-Priority-Range AVP
The User-Priority-Range AVP (AVP Code 557) is of type Grouped and
specifies an inclusive range to match the user_priority parameter
specified in [IEEE802.1D]. An Ethernet packet containing the
user_priority parameter matches this classifier if the value is
greater than or equal to Low-User-Priority and less than or equal to
High-User-Priority. If this AVP is omitted, then comparison of the
IEEE 802.1D user_priority parameter for this classifier is
irrelevant.
User-Priority-Range ::= < AVP Header: 557 >
* [ Low-User-Priority ]
* [ High-User-Priority ]
* [ AVP ]
4.1.8.24. Low-User-Priority AVP
The Low-User-Priority AVP (AVP Code 558) is of type Unsigned32. The
value MUST be in the range from 0 to 7.
4.1.8.25. High-User-Priority AVP
The High-User-Priority AVP (AVP Code 559) is of type Unsigned32. The
value MUST be in the range from 0 to 7.
4.2. Time Of Day AVPs
In many QoS applications, the QoS specification applied to the
traffic flow is conditional upon the time of day when the flow was
observed. The following sections define AVPs that can be used to
express one or more time windows that determine when a traffic
treatment action is applicable to a traffic flow.
4.2.1. Time-Of-Day-Condition AVP
The Time-Of-Day-Condition AVP (AVP Code 560) is of type Grouped and
specifies one or more time windows.
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Time-Of-Day-Condition ::= < AVP Header: 560 >
[ Time-Of-Day-Start ]
[ Time-Of-Day-End ]
[ Day-Of-Week-Mask ]
[ Day-Of-Month-Mask ]
[ Month-Of-Year-Mask ]
[ Absolute-Start-Time ]
[ Absolute-End-Time ]
[ Timezone-Flag ]
* [ AVP ]
For example, a time window for 9 a.m. to 5 p.m. (local time) from
Monday to Friday would be expressed as:
Time-Of-Day-Condition = {
Time-Of-Day-Start = 32400;
Time-Of-Day-End = 61200;
Day-Of-Week-Mask =
( MONDAY | TUESDAY | WEDNESDAY | THURSDAY | FRIDAY );
Timezone-Flag = LOCAL;
}
4.2.2. Time-Of-Day-Start AVP
The Time-Of-Day-Start AVP (AVP Code 561) is of type Unsigned32. The
value MUST be in the range from 0 to 86400. The value of this AVP
specifies the start of an inclusive time window expressed as the
offset in seconds from midnight. If this AVP is absent from the
Time-Of-Day-Condition AVP, the time window starts at midnight.
4.2.3. Time-Of-Day-End AVP
The Time-Of-Day-End AVP (AVP Code 562) is of type Unsigned32. The
value MUST be in the range from 1 to 86400. The value of this AVP
specifies the end of an inclusive time window expressed as the offset
in seconds from midnight. If this AVP is absent from the Time-Of-
Day-Condition AVP, the time window ends one second before midnight.
4.2.4. Day-Of-Week-Mask AVP
The Day-Of-Week-Mask AVP (AVP Code 563) is of type Unsigned32. The
value is a bit mask that specifies the day of the week for the time
window to match. This document specifies the following bits:
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Bit | Name
------+------------
0 | SUNDAY
1 | MONDAY
2 | TUESDAY
3 | WEDNESDAY
4 | THURSDAY
5 | FRIDAY
6 | SATURDAY
The bit MUST be set for the time window to match on the corresponding
day of the week. Bit 0 is the least significant bit and unused bits
MUST be cleared. If this AVP is absent from the Time-Of-Day-
Condition AVP, the time windows match on all days of the week.
4.2.5. Day-Of-Month-Mask AVP
The Day-Of-Month AVP (AVP Code 564) is of type Unsigned32. The value
MUST be in the range from 0 to 2147483647. The value is a bit mask
that specifies the days of the month where bit 0 represents the first
day of the month through to bit 30, which represents the last day of
the month. The bit MUST be set for the time window to match on the
corresponding day of the month. Bit 0 is the least significant bit
and unused bits MUST be cleared. If this AVP is absent from the
Time-Of-Day-Condition AVP, the time windows match on all days of the
month.
4.2.6. Month-Of-Year-Mask AVP
The Month-Of-Year-Mask AVP (AVP Code 565) is of type Unsigned32. The
value is a bit mask that specifies the months of the year for the
time window to match. This document specifies the following bits:
Bit | Name
------+-----------
0 | JANUARY
1 | FEBRUARY
2 | MARCH
3 | APRIL
4 | MAY
5 | JUNE
6 | JULY
7 | AUGUST
8 | SEPTEMBER
9 | OCTOBER
10 | NOVEMBER
11 | DECEMBER
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The bit MUST be set for the time window to match on the corresponding
month of the year. Bit 0 is the least significant bit and unused
bits MUST be cleared. If this AVP is absent from the Time-Of-Day-
Condition AVP, the time windows match during all months of the year.
4.2.7. Absolute-Start-Time AVP
The Absolute-Start-Time AVP (AVP Code 566) is of type Time. The
value of this AVP specifies the time in seconds since January 1,
1900, 00:00 UTC when the time window starts. If this AVP is absent
from the Time-Of-Day-Condition AVP, the time window starts on January
1, 1900, 00:00 UTC.
4.2.8. Absolute-Start-Fractional-Seconds AVP
The Absolute-Start-Fractional-Seconds AVP (AVP Code 567) is of type
Unsigned32. The value specifies the fractional seconds that are
added to Absolute-Start-Time value in order to determine when the
time window starts. If this AVP is absent from the Time-Of-Day-
Condition AVP, then the fractional seconds are assumed to be zero.
4.2.9. Absolute-End-Time AVP
The Time-Of-Day-End AVP (AVP Code 568) is of type Time. The value of
this AVP specifies the time in seconds since January 1, 1900, 00:00
UTC when the time window ends. If this AVP is absent from the Time-
Of-Day-Condition AVP, then the time window is open-ended.
4.2.10. Absolute-End-Fractional-Seconds AVP
The Absolute-End-Fractional-Seconds AVP (AVP Code 569) is of type
Unsigned32. The value specifies the fractional seconds that are
added to Absolute-End-Time value in order to determine when the time
window ends. If this AVP is absent from the Time-Of-Day-Condition
AVP, then the fractional seconds are assumed to be zero.
4.2.11. Timezone-Flag AVP
The Timezone-Flag AVP (AVP Code 570) is of type Enumerated and
indicates whether the time windows are specified in UTC, local time,
at the managed terminal or as an offset from UTC. If this AVP is
absent from the Time-Of-Day-Condition AVP, then the time windows are
in UTC.
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This document defines the following values:
Value | Name and Semantic
------+--------------------------------------------------
0 | UTC - The time windows are expressed in UTC.
1 | LOCAL - The time windows are expressed in local
| time at the managed terminal.
2 | OFFSET - The time windows are expressed as an
| offset from UTC (see Timezone-Offset AVP).
4.2.12. Timezone-Offset AVP
The Timezone-Offset AVP (AVP Code 571) is of type Integer32. The
value of this AVP MUST be in the range from -43200 to 43200. It
specifies the offset in seconds from UTC that was used to express
Time-Of-Day-Start, Time-Of-Day-End, Day-Of-Week-Mask, Day-Of-Month-
Mask, and Month-Of-Year-Mask AVPs. This AVP MUST be present if the
Timezone-Flag AVP is set to OFFSET.
5. Actions
This section defines the actions associated with a rule.
5.1. Treatment-Action AVP
The Treatment-Action AVP (AVP Code 572) is of type Enumerated and
lists the actions that are associated with the condition part of a
rule. The following actions are defined in this document:
0: drop
1: shape
2: mark
3: permit
drop:
This action indicates that the respective traffic MUST be dropped.
shape:
[RFC 2475] describes shaping as "the process of delaying packets
within a traffic stream to cause it to conform to some defined
traffic profile". When the action is set to 'shape', the QoS-
Parameters AVP SHALL contain QoS information AVPs, such as the
TMOD-1 and Bandwidth AVPs [RFC 5624], that indicate how to shape
the traffic described by the condition part of the rule.
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mark:
[RFC 2475] describes marking as "the process of setting the DS
codepoint in a packet based on defined rules". When the action is
set to 'mark', the QoS-Parameters AVP SHALL contain QoS
information AVPs, such as the PHB-Class AVP [RFC 5624], that
indicate the Diffserv marking to be applied to the traffic
described by the condition part of the rule.
permit:
The 'permit' action is the counterpart to the 'drop' action used
to allow traffic that matches the condition part of a rule to
bypass.
[RFC 2475] also describes an action called 'policing' as "the process
of discarding packets (by a dropper) within a traffic stream in
accordance with the state of a corresponding meter enforcing a
traffic profile". This behavior is modeled in the Filter-Rule
through the inclusion of the Excess-Treatment AVP containing a
Treatment-Action AVP set to 'drop'.
Further action values can be registered, as described in
Section 10.3.
5.2. QoS-Profile-Id AVP
The QoS-Profile-Id AVP (AVP Code 573) is of type Unsigned32 and
contains a QoS profile template identifier. An initial QoS profile
template is defined with value of 0 and can be found in [RFC 5624].
The registry for the QoS profile templates is created with the same
document.
5.3. QoS-Profile-Template AVP
The QoS-Profile-Template AVP (AVP Code 574) is of type Grouped and
defines the namespace of the QoS profile (indicated in the Vendor-ID
AVP) followed by the specific value for the profile.
The Vendor-Id AVP contains a 32-bit IANA Private Enterprise Number
(PEN), and the QoS-Profile-Id AVP contains the template identifier
assigned by the vendor. The vendor identifier of zero (0) is used
for the IETF.
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QoS-Profile-Template ::= < AVP Header: 574 >
{ Vendor-Id }
{ QoS-Profile-Id }
* [ AVP ]
5.4. QoS-Semantics
The QoS-Semantics AVP (AVP Code 575) is of type Enumerated and
provides the semantics for the QoS-Profile-Template and QoS-
Parameters AVPs in the Filter-Rule AVP.
This document defines the following values:
(0): QoS-Desired
(1): QoS-Available
(2): QoS-Delivered
(3): Minimum-QoS
(4): QoS-Authorized
The semantics of the QoS parameters depend on the information
provided in the list above. The semantics of the different values
are as follows:
Object Type Direction Semantic
---------------------------------------------------------------------
QoS-Desired C->S Client requests authorization of the
indicated QoS.
QoS-Desired C<-S NA
QoS-Available C->S Admission Control at client indicates
that this QoS is available. (note 1)
QoS-Available C<-S Admission Control at server indicates
that this QoS is available. (note 2)
QoS-Delivered C->S Client is reporting the actual QoS
delivered to the terminal.
QoS-Delivered C<-S NA
Minimum-QoS C->S Client is not interested in authorizing
QoS that is lower than the indicated QoS.
Minimum-QoS C<-S Client must not provide QoS guarantees
lower than the indicated QoS.
QoS-Authorized C->S NA
QoS-Authorized C<-S Server authorizes the indicated QoS.
Legend:
C: Diameter client
S: Diameter server
NA: Not applicable to this document;
no semantic defined in this specification
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Notes:
(1) QoS-Available in this direction indicates to the server that
any QoS-Authorized or Minimum-QoS must be less than this
indicated QoS.
(2) QoS-Available in this direction is only useful when the AAA
server performs admission control and knows about the resources
in the network.
5.5. QoS-Parameters AVP
The QoS-Parameters AVP (AVP Code 576) is of type Grouped and contains
Quality of Service parameters. These parameters are defined in
separate documents and depend on the indicated QoS profile template
of the QoS-Profile-Template AVP. For an initial QoS parameter
specification, see [RFC 5624].
QoS-Parameters ::= < AVP Header: 576 >
* [ AVP ]
5.6. Excess-Treatment AVP
The Excess-Treatment AVP (AVP Code 577) is of type Grouped and
indicates how out-of-profile traffic, i.e., traffic not covered by
the original QoS-Profile-Template and QoS-Parameters AVPs, is
treated. The additional Treatment-Action, QoS-Profile-Template, and
QoS-Parameters AVPs carried inside the Excess-Treatment AVP provide
information about the QoS treatment of the excess traffic. In case
the Excess-Treatment AVP is absent, then the treatment of the out-of-
profile traffic is left to the discretion of the node performing QoS
treatment.
Excess-Treatment ::= < AVP Header: 577 >
{ Treatment-Action }
[ QoS-Profile-Template ]
[ QoS-Parameters ]
* [ AVP ]
6. QoS Capability Indication
The QoS-Capability AVP (AVP Code 578) is of type Grouped and contains
a list of supported Quality of Service profile templates (and
therefore the support of the respective parameter AVPs).
The QoS-Capability AVP may be used for a simple announcement of the
QoS capabilities and QoS profiles supported by a peer. It may also
be used to negotiate a mutually supported set of QoS capabilities and
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QoS profiles between two peers. In such a case, handling of failed
negotiations is application and/or deployment specific.
QoS-Capability ::= < AVP Header: 578 >
1*{ QoS-Profile-Template }
* [ AVP ]
The QoS-Profile-Template AVP is defined in Section 5.3.
7. Examples
This section shows a number of signaling flows where QoS negotiation
and authorization are part of the conventional NASREQ, EAP, or Credit
Control applications message exchanges. The signaling flows for the
Diameter QoS Application are described in [DIAMETER-QOS].
7.1. Diameter EAP with QoS Information
Figure 2 shows a simple signaling flow where a Network Access Server
(NAS) (Diameter Client) announces its QoS awareness and capabilities
included into the DER message and as part of the access
authentication procedure. Upon completion of the EAP exchange, the
Diameter server provides a pre-provisioned QoS profile with the QoS-
Semantics in the Filter-Rule AVP set to 'QoS-Authorized', to the NAS
in the final Diameter-EAP-Answer (DEA) message.
Korhonen, et al. Standards Track PAGE 30
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End Diameter Diameter
Host Client Server
| | |
| (initiate EAP) | |
|<----------------------------->| |
| | Diameter-EAP-Request |
| | EAP-Payload(EAP Start) |
| | QoS-Capability |
| |------------------------------->|
| | |
| | Diameter-EAP-Answer |
| Result-Code=DIAMETER_MULTI_ROUND_AUTH |
| | EAP-Payload(EAP Request #1) |
| |<-------------------------------|
| EAP Request(Identity) | |
|<------------------------------| |
: : :
: <<<more message exchanges>>> :
: : :
| | |
| EAP Response #N | |
|------------------------------>| |
| | Diameter-EAP-Request |
| | EAP-Payload(EAP Response #N) |
| |------------------------------->|
| | |
| | Diameter-EAP-Answer |
| | Result-Code=DIAMETER_SUCCESS |
| | EAP-Payload(EAP Success) |
| | (authorization AVPs) |
| | QoS-Resources(QoS-Authorized) |
| |<-------------------------------|
| | |
| EAP Success | |
|<------------------------------| |
| | |
Figure 2: Example of a Diameter EAP Enhanced with QoS Information
Korhonen, et al. Standards Track PAGE 31
RFC 5777 QoS Attributes for Diameter February 2010
7.2. Diameter NASREQ with QoS Information
Figure 3 shows a similar pre-provisioned QoS signaling as in Figure 2
but using the NASREQ application instead of EAP application.
End Diameter
Host NAS Server
| | |
| Start Network | |
| Attachment | |
|<---------------->| |
| | |
| |AA-Request |
| |NASREQ-Payload |
| |QoS-Capability |
| +----------------------------->|
| | |
| | AA-Answer|
| Result-Code=DIAMETER_MULTI_ROUND_AUTH|
| NASREQ-Payload(NASREQ Request #1)|
| |<-----------------------------+
| | |
| Request | |
|<-----------------+ |
| | |
: : :
: <<<more message exchanges>>> :
: : :
| Response #N | |
+----------------->| |
| | |
| |AA-Request |
| |NASREQ-Payload ( Response #N )|
| +----------------------------->|
| | |
| | AA-Answer|
| | Result-Code=DIAMETER_SUCCESS|
| | (authorization AVPs)|
| | QoS-Resources(QoS-Authorized)|
| |<-----------------------------+
| | |
| Success | |
|<-----------------+ |
| | |
Figure 3: Example of a Diameter NASREQ Enhanced with QoS Information
Korhonen, et al. Standards Track PAGE 32
RFC 5777 QoS Attributes for Diameter February 2010
7.3. QoS Authorization
Figure 4 shows an example of authorization-only QoS signaling as part
of the NASREQ message exchange. The NAS provides the Diameter server
with the "QoS-Desired" QoS-Semantics AVP included in the QoS-
Resources AVP. The Diameter server then either authorizes the
indicated QoS or rejects the request and informs the NAS about the
result. In this scenario, the NAS does not need to include the QoS-
Capability AVP in the AAR message as the QoS-Resources AVP implicitly
does the same and also the NAS is authorizing a specific QoS profile,
not a pre-provisioned one.
End Diameter
Host NAS Server
| | |
| | |
| QoS Request | |
+----------------->| |
| | |
| |AA-Request |
| |Auth-Request-Type=AUTHORIZE_ONLY
| |NASREQ-Payload |
| |QoS-Resources(QoS-Desired) |
| +----------------------------->|
| | |
| | AA-Answer|
| | NASREQ-Payload(Success)|
| | QoS-Resources(QoS-Authorized)|
| |<-----------------------------+
| Accept | |
|<-----------------+ |
| | |
| | |
| | |
Figure 4: Example of an Authorization-Only Message Flow
7.4. Diameter Server Initiated Re-Authorization of QoS
Figure 5 shows a message exchange for a Diameter server-initiated QoS
re-authorization procedure. The Diameter server sends the NAS a Re-
Auth Request (RAR) message requesting re-authorization for an
existing session and the NAS acknowledges it with a RAA message. The
NAS is aware of its existing QoS profile and information for the
ongoing session that the Diameter server requested for re-
Korhonen, et al. Standards Track PAGE 33
RFC 5777 QoS Attributes for Diameter February 2010
authorization. Thus, the NAS must initiate re-authorization of the
existing QoS profile. The re-authorization procedure is the same as
in Figure 4.
End Diameter
Host NAS Server
| | |
| | |
: : :
: <<<Initial Message Exchanges>>> :
: : :
| | |
| | RA-Request |
| |<-----------------------------+
| | |
| |RA-Answer |
| |Result-Code=DIAMETER_SUCCESS |
| +----------------------------->|
| | |
| | |
| |AA-Request |
| |NASREQ-Payload |
| |Auth-Request-Type=AUTHORIZE_ONLY
| |QoS-Resources(QoS-Desired) |
| +----------------------------->|
| | |
| | AA-Answer|
| | Result-Code=DIAMETER_SUCCESS|
| | (authorization AVPs)|
| | QoS-Resources(QoS-Authorized)|
| |<-----------------------------+
| | |
Figure 5: Example of a Server-Initiated Re-Authorization Procedure
7.5. Diameter Credit Control (CC) with QoS Information
In this example, the CC client includes a QoS authorization request
(QoS-Semantics=QoS-Desired) in the initial Credit Control Request
(CCR). The CC server responds with a Credit Control Answer (CCA),
which includes the granted resources with an authorized QoS
definition (QoS-Semantics=QoS-Authorized) and the CC client proceeds
to deliver service with the specified QoS.
At the end of service, the CC client reports the units used and the
QoS level at which those units were delivered (QoS-Semantics=QoS-
Delivered). The end of service could occur because the credit
resources granted to the user were exhausted or the service was been
Korhonen, et al. Standards Track PAGE 34
RFC 5777 QoS Attributes for Diameter February 2010
successfully delivered or the service was terminated, e.g., because
the Service Element could not deliver the service at the authorized
QoS level.
Service Element
End User (CC Client) CC Server
| | |
|(1) Service Request | |
|-------------------->| |
| |(2) CCR (Initial, |
| | QoS-Resources(QoS-Desired)) |
| |--------------------------------->|
| |(3) CCA (Granted-Units, |
| | QoS-Resources(QoS-Authorized))|
| |<---------------------------------|
|(4) Service Delivery | |
|<------------------->| |
| | |
|(5) End of Service | |
|-------------------->| |
| |(6) CCR (Termination, Used-Units, |
| | QoS-Resources(QoS-Delivered)) |
| |--------------------------------->|
| |(7) CCA |
| |<---------------------------------|
Figure 6: Example of a Diameter Credit Control with QoS Information
7.6. Classifier Examples
Example: Classify all packets from hosts on subnet 192.0.2.0/24 to
ports 80, 8090 or 443 on web servers 192.0.2.123, 192.0.2.124,
192.0.2.125.
Korhonen, et al. Standards Track PAGE 35
RFC 5777 QoS Attributes for Diameter February 2010
Classifier = {
Classifier-Id = "web_svr_example";
Protocol = TCP;
Direction = OUT;
From-Spec = {
IP-Address-Mask = {
IP-Address = 192.0.2.0;
IP-Bit-Mask-Width = 24;
}
}
To-Spec = {
IP-Address = 192.0.2.123;
IP-Address = 192.0.2.124;
IP-Address = 192.0.2.125;
Port = 80;
Port = 8080;
Port = 443;
}
}
Example: Any SIP signaling traffic from a device with a MAC address
of 01:23:45:67:89:ab to servers with IP addresses in the range
192.0.2.90 to 192.0.2.190.
Classifier = {
Classifier-Id = "web_svr_example";
Protocol = UDP;
Direction = OUT;
From-Spec = {
MAC-Address = 01:23:45:67:89:ab;
}
To-Spec = {
IP-Address-Range = {
IP-Address-Start = 192.0.2.90;
IP-Address-End = 192.0.2.190;
}
Port = 5060;
Port = 3478;
Port-Range = {
Port-Start = 16348;
Port-End = 32768;
}
}
}
Korhonen, et al. Standards Track PAGE 36
RFC 5777 QoS Attributes for Diameter February 2010
7.7. QoS Parameter Examples
The following high-level description aims to illustrate the
interworking between the Diameter QoS AVPs defined in this document
and the QoS parameters defined in [RFC 5624].
Consider the following example where a rule should be installed that
limits traffic to 1 Mbit/s and where out-of-profile traffic shall be
dropped. The Classifiers are ignored in this example.
This would require the Treatment-Action AVP to be set to 'shape' and
the QoS-Parameters AVP carries the Bandwidth AVP indicating the 1
Mbit/s limit. The Treatment-Action carried inside the Excess-
Treatment AVP would be set to 'drop'.
In a second, more complex scenario, we consider traffic marking with
Diffserv. In-profile traffic (of 5 Mbit/s in our example) shall be
associated with a particular PHB-Class "X". Out-of-profile traffic
shall belong to a different PHB-Class, in our example "Y".
This configuration would require the Treatment-Action AVP to be set
to 'mark'. The QoS-Parameters AVPs for the traffic conforming of the
profile contains two AVPs, namely, the TMOD-1 AVP and the PHB-Class
AVP. The TMOD-1 AVP describes the traffic characteristics, namely, 5
Mbit/s, and the PHB-Class AVP is set to class "X". Then, the Excess-
Treatment AVP has to be included with the Treatment-Action AVP set to
'mark' and the QoS-Parameters AVP to carry another PHB-Class AVP
indicating PHB-Class AVP setting to class "Y".
8. Acknowledgments
We would like to thank Victor Fajardo, Tseno Tsenov, Robert Hancock,
Jukka Manner, Cornelia Kappler, Xiaoming Fu, Frank Alfano, Tolga
Asveren, Mike Montemurro, Glen Zorn, Avri Doria, Dong Sun, Tina Tsou,
Pete McCann, Georgios Karagiannis, Elwyn Davies, Max Riegel, Yong Li,
and Eric Gray for their comments. We thank Victor Fajardo for his
job as PROTO document shepherd. Finally, we would like to thank Lars
Eggert, Magnus Westerlund, Adrian Farrel, Lisa Dusseault, Ralph
Droms, and Eric Gray for their feedback during the IESG review phase.
9. Contributors
Max Riegel contributed the VLAN sections.
Korhonen, et al. Standards Track PAGE 37
RFC 5777 QoS Attributes for Diameter February 2010
10. IANA Considerations
10.1. AVP Codes
IANA has allocated codes from the "AVP Codes" registry under
Authentication, Authorization, and Accounting (AAA) Parameters for
the following AVPs that are defined in this document.
+-------------------------------------------------------------------+
| AVP Section |
| Attribute Name Code Defined Data Type |
+-------------------------------------------------------------------+
|QoS-Resources 508 3.1 Grouped |
|Filter-Rule 509 3.2 Grouped |
|Filter-Rule-Precedence 510 3.3 Unsigned32 |
|Classifier 511 4.1.1 Grouped |
|Classifier-ID 512 4.1.2 OctetString |
|Protocol 513 4.1.3 Enumerated |
|Direction 514 4.1.4 Enumerated |
|From-Spec 515 4.1.5 Grouped |
|To-Spec 516 4.1.6 Grouped |
|Negated 517 4.1.7.1 Enumerated |
|IP-Address 518 4.1.7.2 Address |
|IP-Address-Range 519 4.1.7.3 Grouped |
|IP-Address-Start 520 4.1.7.4 Address |
|IP-Address-End 521 4.1.7.5 Address |
|IP-Address-Mask 522 4.1.7.6 Grouped |
|IP-Mask-Bit-Mask-Width 523 4.1.7.7 Unsigned32 |
|MAC-Address 524 4.1.7.8 OctetString |
|MAC-Address-Mask 525 4.1.7.9 Grouped |
|MAC-Address-Mask-Pattern 526 4.1.7.10 OctetString |
|EUI64-Address 527 4.1.7.11 OctetString |
|EUI64-Address-Mask 528 4.1.7.12 Grouped |
|EUI64-Address-Mask-Pattern 529 4.1.7.13 OctetString |
|Port 530 4.1.7.14 Integer32 |
|Port-Range 531 4.1.7.15 Grouped |
|Port-Start 532 4.1.7.16 Integer32 |
|Port-End 533 4.1.7.17 Integer32 |
|Use-Assigned-Address 534 4.1.7.18 Enumerated |
|Diffserv-Code-Point 535 4.1.8.1 Enumerated |
|Fragmentation-Flag 536 4.1.8.2 Enumerated |
|IP-Option 537 4.1.8.3 Grouped |
|IP-Option-Type 538 4.1.8.4 Enumerated |
|IP-Option-Value 539 4.1.8.5 OctetString |
|TCP-Option 540 4.1.8.6 Grouped |
|TCP-Option-Type 541 4.1.8.7 Enumerated |
|TCP-Option-Value 542 4.1.8.8 OctetString |
|TCP-Flags 543 4.1.8.9 Grouped |
Korhonen, et al. Standards Track PAGE 38
RFC 5777 QoS Attributes for Diameter February 2010
|TCP-Flag-Type 544 4.1.8.10 Unsigned32 |
|ICMP-Type 545 4.1.8.11 Grouped |
|ICMP-Type-Number 546 4.1.8.12 Enumerated |
|ICMP-Code 547 4.1.8.13 Enumerated |
|ETH-Option 548 4.1.8.14 Grouped |
|ETH-Proto-Type 549 4.1.8.15 Grouped |
|ETH-Ether-Type 550 4.1.8.16 OctetString |
|ETH-SAP 551 4.1.8.17 OctetString |
|VLAN-ID-Range 552 4.1.8.18 Grouped |
|S-VID-Start 553 4.1.8.19 Unsigned32 |
|S-VID-End 554 4.1.8.20 Unsigned32 |
|C-VID-Start 555 4.1.8.21 Unsigned32 |
|C-VID-End 556 4.1.8.22 Unsigned32 |
|User-Priority-Range 557 4.1.8.23 Grouped |
|Low-User-Priority 558 4.1.8.24 Unsigned32 |
|High-User-Priority 559 4.1.8.25 Unsigned32 |
|Time-Of-Day-Condition 560 4.2.1 Grouped |
|Time-Of-Day-Start 561 4.2.2 Unsigned32 |
|Time-Of-Day-End 562 4.2.3 Unsigned32 |
|Day-Of-Week-Mask 563 4.2.4 Unsigned32 |
|Day-Of-Month-Mask 564 4.2.5 Unsigned32 |
|Month-Of-Year-Mask 565 4.2.6 Unsigned32 |
|Absolute-Start-Time 566 4.2.7 Time |
|Absolute-Start-Fractional-Seconds 567 4.2.8 Unsigned32 |
|Absolute-End-Time 568 4.2.9 Time |
|Absolute-End-Fractional-Seconds 569 4.2.10 Unsigned32 |
|Timezone-Flag 570 4.2.11 Enumerated |
|Timezone-Offset 571 4.2.12 Integer32 |
|Treatment-Action 572 5.1 Grouped |
|QoS-Profile-Id 573 5.2 Unsigned32 |
|QoS-Profile-Template 574 5.3 Grouped |
|QoS-Semantics 575 5.4 Enumerated |
|QoS-Parameters 576 5.5 Grouped |
|Excess-Treatment 577 5.6 Grouped |
|QoS-Capability 578 6 Grouped |
+-------------------------------------------------------------------+
10.2. QoS-Semantics IANA Registry
IANA has allocated a new registry under Authentication,
Authorization, and Accounting (AAA) Parameters for the QoS-Semantics
AVP. The following values are allocated by this specification:
(0): QoS-Desired
(1): QoS-Available
(2): QoS-Delivered
(3): Minimum-QoS
(4): QoS-Authorized
Korhonen, et al. Standards Track PAGE 39
RFC 5777 QoS Attributes for Diameter February 2010
The definition of new values is subject to the Specification Required
policy [RFC 5226].
10.3. Action
IANA has allocated a new registry under Authentication,
Authorization, and Accounting (AAA) Parameters for the Treatment-
Action AVP. The following values are allocated by this
specification:
0: drop
1: shape
2: mark
3: permit
The definition of new values is subject to the Specification Required
policy [RFC 5226].
11. Security Considerations
This document describes the extension of Diameter for conveying
Quality of Service information. The security considerations of the
Diameter protocol itself have been discussed in RFC 3588 [RFC 3588].
Use of the AVPs defined in this document MUST take into consideration
the security issues and requirements of the Diameter base protocol.
12. References
12.1. Normative References
[IEEE802.1D] IEEE, "IEEE Standard for Local and metropolitan area
networks, Media Access Control (MAC) Bridges", 2004.
[IEEE802.1Q] IEEE, "IEEE Standard for Local and metropolitan area
networks, Virtual Bridged Local Area Networks", 2005.
[IEEE802.1ad] IEEE, "IEEE Standard for Local and metropolitan area
networks, Virtual Bridged Local Area Networks,
Amendment 4: Provider Bridges", 2005.
[IEEE802.2] IEEE, "IEEE Standard for Information technology,
Telecommunications and information exchange between
systems, Local and metropolitan area networks,
Specific requirements, Part 2: Logical Link Control",
1998.
[RFC 2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
Korhonen, et al. Standards Track PAGE 40
RFC 5777 QoS Attributes for Diameter February 2010
[RFC 2474] 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.
[RFC 2780] Bradner, S. and V. Paxson, "IANA Allocation
Guidelines For Values In the Internet Protocol and
Related Headers", BCP 37, RFC 2780, March 2000.
[RFC 3168] Ramakrishnan, K., Floyd, S., and D. Black, "The
Addition of Explicit Congestion Notification (ECN) to
IP", RFC 3168, September 2001.
[RFC 3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and
J. Arkko, "Diameter Base Protocol", RFC 3588,
September 2003.
[RFC 5226] Narten, T. and H. Alvestrand, "Guidelines for Writing
an IANA Considerations Section in RFCs", BCP 26,
RFC 5226, May 2008.
12.2. Informative References
[DIAMETER-QOS] Sun, D., Ed., McCann, P., Tschofenig, H., Tsou, T.,
Doria, A., and G. Zorn, Ed., "Diameter Quality of
Service Application", Work in Progress, October 2009.
[RFC 2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang,
Z., and W. Weiss, "An Architecture for Differentiated
Services", RFC 2475, December 1998.
[RFC 4005] Calhoun, P., Zorn, G., Spence, D., and D. Mitton,
"Diameter Network Access Server Application",
RFC 4005, August 2005.
[RFC 5624] Korhonen, J., Tschofenig, H., and E. Davies, "Quality
of Service Parameters for Usage with Diameter",
RFC 5624, August 2009.
Korhonen, et al. Standards Track PAGE 41
RFC 5777 QoS Attributes for Diameter February 2010
Appendix A. MAC and EUI64 Address Mask Usage Considerations
The MAC and EUI64 address bit masks are generally used in classifying
devices according to Organizationally Unique Identifier (OUI) and/or
address blocks specific to the OUI assignee. The bit masks are not
intended to introduce a structure into the MAC or EUI64 address space
that was not intended by the IEEE.
The MAC address bit mask should be defined as a contiguous series of
"N" set bits followed by a contiguous series of "48 - N" clear bits,
e.g., the MAC address bit mask of 0xFF00FF000000 would not be valid.
Similarly, the EUI64 address bit mask should be defined as a
contiguous series of "N" set bits followed by a contiguous series of
"64 - N" clear bits.
It should also be noted that some OUIs are assigned for use in
applications that require number space management at the organization
level (e.g., LLC/SNAP encoding), and are not commonly used for MAC
addresses.
Korhonen, et al. Standards Track PAGE 42
RFC 5777 QoS Attributes for Diameter February 2010
Authors' Addresses
Jouni Korhonen
Nokia Siemens Networks
Linnoitustie 6
Espoo 02600
Finland
EMail: jouni.korhonen@nsn.com
Hannes Tschofenig
Nokia Siemens Networks
Linnoitustie 6
Espoo 02600
Finland
Phone: +358 (50) 4871445
EMail: Hannes.Tschofenig@gmx.net
URI: http://www.tschofenig.priv.at
Mayutan Arumaithurai
University of Goettingen
EMail: mayutan.arumaithurai@gmail.com
Mark Jones (editor)
Bridgewater Systems
303 Terry Fox Drive, Suite 500
Ottawa, Ontario K2K 3J1
Canada
Phone: +1 613-591-6655
EMail: mark.jones@bridgewatersystems.com
Avi Lior
Bridgewater Systems
303 Terry Fox Drive, Suite 500
Ottawa, Ontario K2K 3J1
Canada
Phone: +1 613-591-6655
EMail: avi@bridgewatersystems.com
Korhonen, et al. Standards Track PAGE 43
Traffic Classification and Quality of Service (QoS) Attributes for Diameter
RFC TOTAL SIZE: 91305 bytes
PUBLICATION DATE: Friday, February 12th, 2010
LEGAL RIGHTS: The IETF Trust (see BCP 78)
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