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/rfc5777.
Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved.
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include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
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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 [RFC3588]. 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 [RFC3588] and was later updated by RFC 4005 [RFC4005].
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
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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 [RFC3588]). The AVP datatypes are also taken from [RFC3588].
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].
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 [RFC5624]). 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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QoS-Profile-Id AVP is set to zero (0), then the AVPs included in the QoS-Parameters AVP are the AVPs defined in [RFC5624].
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.
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.
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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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.
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.
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 [RFC2780].
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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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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.
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.
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 [RFC2474].
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.
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 [RFC2780].
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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.
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 [RFC2780].
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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.
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 [RFC3168], 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 [RFC3168].
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.
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 [RFC2780].
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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 [RFC2780].
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.
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.
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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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.
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.
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.
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.
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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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.
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.
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.
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.
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.
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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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.
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.
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.
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.
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.
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.
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.
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).
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.
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:
This action indicates that the respective traffic MUST be dropped.
shape:
[RFC2475] 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 [RFC5624], that indicate how to shape the traffic described by the condition part of the rule.
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mark:
[RFC2475] 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 [RFC5624], 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.
[RFC2475] 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.
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 [RFC5624]. The registry for the QoS profile templates is created with the same document.
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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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.
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.
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 [RFC5624].
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.
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.
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].
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.
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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.
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-
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authorization. Thus, the NAS must initiate re-authorization of the existing QoS profile. The re-authorization procedure is the same as in Figure 4.
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
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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
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.
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 [RFC5624].
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".
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.
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.
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:
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 [RFC5226].
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 [RFC3588]. Use of the AVPs defined in this document MUST take into consideration the security issues and requirements of the Diameter base protocol.
[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.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
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[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.
[RFC2780] Bradner, S. and V. Paxson, "IANA Allocation Guidelines For Values In the Internet Protocol and Related Headers", BCP 37, RFC 2780, March 2000.
[RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition of Explicit Congestion Notification (ECN) to IP", RFC 3168, September 2001.
[RFC3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and J. Arkko, "Diameter Base Protocol", RFC 3588, September 2003.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.
[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.
[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z., and W. Weiss, "An Architecture for Differentiated Services", RFC 2475, December 1998.
[RFC4005] Calhoun, P., Zorn, G., Spence, D., and D. Mitton, "Diameter Network Access Server Application", RFC 4005, August 2005.
[RFC5624] Korhonen, J., Tschofenig, H., and E. Davies, "Quality of Service Parameters for Usage with Diameter", RFC 5624, August 2009.
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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.
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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