draft-ietf-dime-diameter-qos-01.txt   draft-ietf-dime-diameter-qos-02.txt 
Network Working Group G. Zorn, Ed. Network Working Group G. Zorn, Ed.
Internet-Draft Cisco Systems Internet-Draft
Intended status: Standards Track P. McCann Intended status: Standards Track P. McCann
Expires: January 10, 2008 Motorola Labs Expires: May 22, 2008 Motorola Labs
H. Tschofenig H. Tschofenig
Nokia Siemens Networks Nokia Siemens Networks
T. Tsou T. Tsou
Huawei Huawei
A. Doria A. Doria
Lulea University of Technology Lulea University of Technology
D. Sun D. Sun
Bell Labs/Alcatel-Lucent Bell Labs/Alcatel-Lucent
July 9, 2007 November 19, 2007
Diameter Quality of Service Application Protocol for Diameter Quality of Service Application
draft-ietf-dime-diameter-qos-01.txt draft-ietf-dime-diameter-qos-02.txt
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Abstract Abstract
This document describes a Diameter application that performs This document describes the messages and procedures for the Diameter
Authentication, Authorization, and Accounting for Quality of Service QoS application. The QoS application allows network elements to
(QoS) reservations. This protocol is used by elements along the path interact with Diameter servers when allocating QoS resources in the
of a given application flow to authenticate a reservation request, network. In particular, two modes of operation - Pull and Push are
ensure that the reservation is authorized, and to account for defined.
resources consumed during the lifetime of the application flow.
Clients that implement the Diameter QoS application contact an
authorizing entity/application server that is located somewhere in
the network, allowing for a wide variety of flexible deployment
models.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Framework . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3. Diameter QoS Authorization Session Establishment and
3.1. Network element functional model . . . . . . . . . . . . . 9 Management . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2. Implications of endpoint QoS capabilities . . . . . . . . 11 3.1. Parties involved . . . . . . . . . . . . . . . . . . . . . 6
3.2.1. Category of endpoint QoS capabilities . . . . . . . . 11 3.2. Diameter QoS Authorization Session Establishment . . . . . 6
3.2.2. Interaction modes between authorizing entity and 3.2.1. QoS authorization session establishment for pull
network element . . . . . . . . . . . . . . . . . . . 11 mode . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Authorization schemes . . . . . . . . . . . . . . . . . . 13 3.2.2. QoS authorization session establishment for push
3.3.1. Authorization schemes for pull mode . . . . . . . . . 13 mode . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3.2. Authorization schemes for push mode . . . . . . . . . 16 3.2.3. Discovery and selection of peer Diameter QoS
3.4. QoS Authorization Requirements . . . . . . . . . . . . . . 17 application node . . . . . . . . . . . . . . . . . . . 13
4. Diameter QoS Authorization Session Establishment and 3.3. QoS authorization session re-authorization . . . . . . . . 13
Management . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.3.1. Client-Side Initiated Re-Authorization . . . . . . . . 14
4.1. Parties involved . . . . . . . . . . . . . . . . . . . . . 22 3.3.2. Server-Side Initiated Re-Authorization . . . . . . . . 16
4.2. Diameter QoS Authorization Session Establishment . . . . . 22 3.4. Session Termination . . . . . . . . . . . . . . . . . . . 18
4.3. QoS authorization session re-authorization . . . . . . . . 26 3.4.1. Client-Side Initiated Session Termination . . . . . . 18
4.3.1. Client-Side Initiated Re-Authorization . . . . . . . . 26 3.4.2. Server-Side Initiated Session Termination . . . . . . 19
4.3.2. Server-Side Initiated Re-Authorization . . . . . . . . 28 4. Accounting . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.4. Server-Side Initiated QoS Parameter Provisioning . . . . . 28 5. Diameter QoS Authorization Application Messages . . . . . . . 22
4.5. Session Termination . . . . . . . . . . . . . . . . . . . 29 5.1. QoS-Authorization Request (QAR) . . . . . . . . . . . . . 23
4.5.1. Client-Side Initiated Session Termination . . . . . . 29 5.2. QoS-Authorization Answer (QAA) . . . . . . . . . . . . . . 23
4.5.2. Server-Side Initiated Session Termination . . . . . . 30 5.3. QoS-Install Request (QIR) . . . . . . . . . . . . . . . . 24
5. Accounting . . . . . . . . . . . . . . . . . . . . . . . . . . 32 5.4. QoS-Install Answer (QIA) . . . . . . . . . . . . . . . . . 25
6. Diameter QoS Authorization Application Messages . . . . . . . 33 5.5. Re-Auth-Request (RAR) . . . . . . . . . . . . . . . . . . 25
6.1. QoS-Authorization Request (QAR) . . . . . . . . . . . . . 34 5.6. Re-Auth-Answer (RAA) . . . . . . . . . . . . . . . . . . . 26
6.2. QoS-Authorization Answer (QAA) . . . . . . . . . . . . . . 34 5.7. Accounting Request (ACR) . . . . . . . . . . . . . . . . . 26
6.3. QoS-Install Request (QIR) . . . . . . . . . . . . . . . . 35 5.8. Accounting Answer (ACA) . . . . . . . . . . . . . . . . . 27
6.4. QoS-Install Answer (QIA) . . . . . . . . . . . . . . . . . 36 6. Diameter QoS Authorization Application AVPs . . . . . . . . . 28
6.5. Accounting Request (ACR) . . . . . . . . . . . . . . . . . 36 6.1. Diameter Base Protocol AVPs . . . . . . . . . . . . . . . 28
6.6. Accounting Answer (ACA) . . . . . . . . . . . . . . . . . 37 6.2. Credit Control Application AVPs . . . . . . . . . . . . . 28
7. Diameter QoS Authorization Application AVPs . . . . . . . . . 38 6.3. Accounting AVPs . . . . . . . . . . . . . . . . . . . . . 29
7.1. Diameter Base Protocol AVPs . . . . . . . . . . . . . . . 38 6.4. Diameter QoS Application Defined AVPs . . . . . . . . . . 29
7.2. Credit Control Application AVPs . . . . . . . . . . . . . 38 7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7.3. Accounting AVPs . . . . . . . . . . . . . . . . . . . . . 39 7.1. Example call flow for pull mode . . . . . . . . . . . . . 31
7.4. Diameter QoS Application Defined AVPs . . . . . . . . . . 39 7.2. Example call flow for push mode . . . . . . . . . . . . . 33
8. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 37
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 44 9. Security Considerations . . . . . . . . . . . . . . . . . . . 38
10. Security Considerations . . . . . . . . . . . . . . . . . . . 45 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 39
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 46 11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 40
12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 47 12. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 41
13. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 48 13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 42
14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 49 13.1. Normative References . . . . . . . . . . . . . . . . . . . 42
14.1. Normative References . . . . . . . . . . . . . . . . . . . 49 13.2. Informative References . . . . . . . . . . . . . . . . . . 42
14.2. Informative References . . . . . . . . . . . . . . . . . . 49 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 44
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 51 Intellectual Property and Copyright Statements . . . . . . . . . . 46
Intellectual Property and Copyright Statements . . . . . . . . . . 53
1. Introduction 1. Introduction
To meet the Quality of Service needs of applications such as Voice- This document describes the messages and procedures for the Diameter
over-IP in a heavily loaded network, packets belonging to real-time QoS Application. The QoS Application allows network elements to
application flows must be identified and segregated from other interact with Diameter servers when allocating QoS resources in the
traffic to ensure that bandwidth, delay, and loss rate requirements network.
are met. In addition, new flows should not be added to the network
when it is at or near capacity, which would result in degradation of
quality for all flows carried by the network.
In some cases, these goals can be achieved with mechanisms such as In particular, two modes of operation are defined. In the first,
differentiated services and/or end-to-end congestion and admission called "Pull Mode", the network element queries the Diameter
control. However, when bandwidth is scarce and must be carefully infrastructure for authorization based on some trigger (such as a QoS
managed, such as in cellular networks, or when applications and signaling protocol) that arrives along the data path to be used for
transport protocols lack the capability to perform end-to-end the session. In the second, called "Push Mode", a Diameter server
congestion control, explicit reservation techniques are required. In pro-actively sends a command to the network element(s) to install QoS
these cases, the endpoints will send reservation requests to edge authorization state. This could be triggered, for instance, by off-
and/or interior nodes along the communication path. In addition to path signaling such as SIP-based call control.
verifying whether resources are available, the recipient of a
reservation request must also authenticate and authorize the request,
especially in an environment where the endpoints are not trusted. In
addition, these nodes will generate accounting information about the
resources used and attribute usage to the requesting endpoints. This
will enable the owner of the network element to generate usage-
sensitive billing records and to understand how to allocate new
network capacity.
A variety of protocols could be used to make a QoS request, including A set of command codes pertinent to this QoS application are
RSVP [RFC2210], NSIS [I-D.ietf-nsis-qos-nslp], link-specific specified that allows a single Diameter application to support both
signaling or even SIP/SDP [RFC4566]. This document aims to be Pull and Push modes based on the requirements of network
agnostic to the QoS signaling protocol used and to the QoS model to technologies, deployment scenarios and end-host's capabilities. In
which the signaling is directed. conjunction with parameters defined in other Diameter QoS documents,
this document depicts basic call flow procedures to establish, modify
and terminate a Diameter QoS application session.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
The following terms are used in this document: In addition to the terms defined in other relevant Diameter QoS
documents (e.g., diameter-qos-framework), the following terms are
Application Server used in this document:
An application server is a network entity that exchanges signaling
messages with an application endpoint. It may be a source of
authorization for QoS-enhanced application flows. For example, a
SIP server is one kind of application server.
Application Endpoint
An application endpoint is an entity in an end user device that
exchanges signaling messages with application servers or directly
with other application endpoints. Based on the result of this
signaling, the endpoint may make a request for QoS from the
network. For example, a SIP User Agent is one kind of application
endpoint.
Authorizing Entity
The authorizing entity acts as a Diameter server (and may
collocate with a subscriber database) responsible for authorizing
QoS requests for a particular application flow or aggregate. It
may be a standalone entity or integrated with an application
server. This entity corresponds to the Policy Decision Point
(PDP) (see [RFC2753]).
AAA Cloud
An infrastructure of AAA entities (clients, agents, servers) based
on a AAA protocol, which provides trusted secure connections
between them. It offers authentication, authorization and
accounting services to applications in flexible local and roaming
scenarios. Diameter [RFC3588] and RADIUS [RFC2865] are both
widely deployed AAA protocols.
Network Element (NE)
QoS aware router that acts as Diameter client that implements the
Diameter QoS application in the context of this document. For
almost all scenarios this entity triggers the protocol interaction
described in this document. This entity corresponds to the Policy
Enforcement Point (PEP) (see [RFC2753]).
Pull Mode
In this mode, the QoS authorization process is invoked by the QoS
reservation request received from the endpoint. The Network
Element then requests the QoS authorization decision from the
Authorizing entity.
Push Mode
In this mode, the QoS authorization process is invoked by the
request from Application Server or local policies in the
Authorizing Entity. The Authorizing Entity then installs the QoS
authorization decision to the Network Element initiatively.
3. Framework
The Diameter QoS application runs between a network element (acting
as a Diameter client) and the resource authorizing entity (acting as
a Diameter server). A high-level picture of the resulting
architecture is shown in Figure 1.
+-------+---------+
| Authorizing |
| Entity |
|(Diameter Server)|
+-------+---------+
|
|
/\-----+-----/\
//// \\\\
|| AAA Cloud ||
| (Diameter application) |
|| ||
\\\\ ////
\-------+-----/
|
+---+--+ +-----+----+ +---+--+
| | | NE | | | Media
+ NE +===+(Diameter +===+ NE +=============>>
| | | Client) | | | Flow
+------+ +----------+ +------+
Figure 1: An Architecture supporting QoS-AAA
Figure 1 depicts network elements through which media flows need to
pass, a cloud of AAA servers, and an authorizing entity. Note that
there may be more than one router that needs to interact with the AAA
cloud along the path of a given application flow, although the figure
only depicts one for clarity.
In some deployment scenarios, QoS aware network elements may request
authorization through the AAA cloud based on an incoming QoS
reservation request. The network element will route the request to a
designated authorizing entity. The authorizing entity will return
the result of the authorization decision. In other deployment
scenarios, the authorization will be initiated upon dynamic
application state, so that the request must be authenticated and
authorized based on information from one or more application servers.
If defined properly, the interface between the routers and AAA cloud
would be identical in both cases. Routers are therefore insulated
from the details of particular applications and need not know that
application servers are involved at all. Also, the AAA cloud would
naturally encompass business relationships such as those between
network operators and third-party application providers, enabling
flexible intra- or inter-domain authorization, accounting, and
settlement.
3.1. Network element functional model
Figure 2 depicts a logical operational model of resource management
in a router.
+-----------------------------------------------------+
| DIAMETER Client |
| Functionality |
| +---------------++---------------++---------------+ |
| | User || Authorization || Accounting | |
| | Authentication|| of QoS || for QoS | |
| +---------------+| Requests || Traffic | |
| +---------------++---------------+ |
+-----------------------------------------------------+
^
v
+--------------+ +----------+
|QoS Signaling | | Resource |
|Msg Processing|<<<<<>>>>>>>|Management|
+--------------+ +----------+
. ^ | * ^
| v . * ^
+-------------+ * ^
|Signaling msg| * ^
| Processing | * V
+-------------+ * V
| | * V
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
. . * V
| | * .............................
. . * . Traffic Control .
| | * . +---------+.
. . * . |Admission|.
| | * . | Control |.
+----------+ +------------+ . +---------+.
<-.-| Input | | Outgoing |-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.->
| Packet | | Interface | .+----------+ +---------+.
===>|Processing|====| Selection |===.| Packet |====| Packet |.=>
| | |(Forwarding)| .|Classifier| Scheduler|.
+----------+ +------------+ .+----------+ +---------+.
.............................
<.-.-> = signaling flow
=====> = data flow (sender --> receiver)
<<<>>> = control and configuration operations
****** = routing table manipulation
Figure 2: Network element functional model
Processing of incoming QoS reservation requests includes three
actions: admission control, authorization and resource reservation.
The admission control function provides information for available
resources and determines whether there are enough resources to
fulfill the request. Authorization is performed by the Diameter
client function which involves contacting an authorization entity
through the AAA cloud shown in Section 3. If both checks are
successful, the authorized QoS parameters are set in the packet
classifier and the packet scheduler. Note that the parameters passed
to the Traffic Control function may be different from requested QoS
(depending on the authorization decision). Once the requested
resource is granted, the Resource Management function provides
accounting information to the Authorizing entity using the Diameter
client function.
3.2. Implications of endpoint QoS capabilities
3.2.1. Category of endpoint QoS capabilities
The QoS capabilities of endpoints are varied, which can be
categorized as follows:
o Category 1 endpoint: Has no QoS capability at both application and
network levels. This type of endpoint may set up a connection
through application signaling, but it is unable to specify any
resource/QoS requirements either through application signaling
e.g. SIP or through network signaling e.g. RSVP or NSIS (or does
not support network signaling at all).
o Category 2 endpoint: Only has QoS capability at the application
level. This type of endpoint is able to set up a connection
through application signaling with certain resource/QoS
requirements (e.g. application attributes), but it is unable to
specify any network level resource/QoS requirements (e.g., network
QoS class) through network signaling e.g., RSVP or NSIS (or does
not support network layer signaling at all).
o Category 3: endpoint: Has QoS capability at the network level.
This type of endpoint may set up a connection through application
signaling and translate service characteristics into network
resource/QoS requirements (e.g. network QoS class) locally, and
request the resources through network signaling e.g. RSVP or
NSIS.
3.2.2. Interaction modes between authorizing entity and network element
Different QoS mechanisms are employed in packet networks. Those QoS
mechanisms can be categorized into two schemes: IntServ and DiffServ.
In the IntServ scheme, network signaling e.g RSVP, NSIS, or link
specific signaling is commonly used to initiate a request from
endpoint for desired QoS resource of media flow. In the DiffServ
scheme, the QoS resources are provisioned based on some predefined
QoS service classes instead of endpoint initiated per flow based QoS
request.
It is obvious that the eligible QoS scheme is correlated to the
endpoint's capability in the context of QoS authorization. Since
category 1 and 2 endpoints cannot initiate the QoS resource requests
through the network signaling, the IntServ model is not applicable to
them in general. Depending on network technology and operator's
demand, a category 3 endpoint may either make use of the network
signaling for requesting the resource or not perform the request.
The diversity of QoS capabilities of endpoints and QoS schemes of
network technology leads to the distinction on the interaction mode
between QoS authorization system and underlying network elements.
When the IntServ scheme is employed by category 3 endpoint, the
authorization process is typically initiated by network element when
a trigger such as the network signaling is received from the
endpoint. In the DiffServ scheme, since the network element is
unable to request the resource authorization on its own initiative,
the authorization process is typically triggered upon either the
request of application servers or policies defined by the operator.
As a consequence, two interaction modes are needed in support of
different combinations of QoS schemes and endpoint's QoS
capabilities. Push mode and Pull mode.
o Push mode: The QoS authorization process is triggered by
application servers or local network conditions (e.g. time of day
on resource usage and QoS classes), and the authorization
decisions are installed by the authorzing entity to the network
element on its own initiative without explicit request. In order
to support the push mode, the authorizing entity (i.e. Diameter
server) should be able to initiate a Diameter authorization
session to communicate with the network element (i.e. Diameter
client) without any pre-established connection from the network
element.
o Pull mode: The QoS authorization process is triggered by the
network signaling received from end user equipments or by the
local event in the network element according to pre-configured
policies, and authorization decisions are produced upon the
request of the network element. In order to support the pull
mode, the network element (i.e. Diameter client) will initiate a
Diameter authorization session to communicate with authorizing
entity (i.e. Diameter server).
For category 1 and 2 endpoints, the Push mode is required, in
particular, category 1 endpoint requires network initiated push mode
and category 2 endpoint may use both them. For category 3 endpoint,
either push mode or pull mode is doable.
The Push mode is applicable to certain networks, for example, Cable
network, DSL, Ethernet, Diffserv enabled IP/MPLS as defined by other
SDOs e.g. ETSI TISPAN and ITU-T. The Pull mode is more appropriate
to IntServ enabled IP networks or certain wireless networks such as
GPRS networks as defined by 3GPP/PP2. Some networks e.g. WiMAX may
require both Push and Pull modes.
3.3. Authorization schemes
3.3.1. Authorization schemes for pull mode
Three basic authorization schemes for pull mode exist: one two-party
and two three-party schemes. The notation adopted here is in respect
to the entity that performs the QoS authorization. The
authentication of the QoS requesting entity might be done at the
network element as part of the QoS signaling protocol, or by an off-
path protocol run (on the application layer or for network access
authentication) or the authorizing entity might be contacted with
request for authentication and authorization of the QoS requesting
entity. From the Diameter QoS application's point of view these
schemes differ in type of information that need to be carried. Here
we focus on the 'Three party scheme' (Figure 3) and the Token-based
three party scheme' (Figure 4). With the 'Two party scheme' the QoS
resource requesting entity is authenticated by the Network Element
and the authorization decision is made either locally at the Network
Element itself or offloaded to a trusted entity (most likely within
the same administrative domain). In the former case no Diameter QoS
protocol interaction is required.
+--------------+
| Entity |
| authorizing | <......+
| resource | .
| request | .
+------------+-+ .
--^----------|-- . .
///// | | \\\\\ .
// | | \\ .
| QoS | QoS AAA | QoS |.
| authz| protocol |authz |.
| req.| | res. |.
\\ | | // .
\\\\\ | | ///// .
QoS --|----------v-- . .
+-------------+ request +-+------------+ .
| Entity |----------------->| NE | .
| requesting | | performing | .
| resource |granted / rejected| QoS | <.....+
| |<-----------------| reservation | financial
+-------------+ +--------------+ settlement
Figure 3: Three Party Scheme
With the 'Three party scheme' a QoS reservation request that arrives
at the Network Element is forwarded to the Authorizing Entity (e.g.,
in the user's home network), where the authorization decision is
made. A business relationship, such as a roaming agreement, between
the visited network and the home network ensures that the visited
network is compensated for the resources consumed by the user via the
home network.
financial settlement
...........................+
Authorization V ------- .
Token Request +--------------+ / QoS AAA \ .
+-------------->| | / protocol \ .
| | Authorizing +--------------+ \ .
| | Entity | | | | .
| +------+ |<--+----+ | | .
| | +--------------+ |QoS | |QoS |.
| | |authz| |authz|.
| |Authorization |req.+| |res. |.
| |Token |Token| | |.
| | | | | . | .
| | \ | | . / .
| | \ | | / .
| | QoS request |-----V . .
+-------------+ + Authz. Token +--------+-----+ .
| Entity |----------------->| NE | .
| requesting | | performing | .
| resource |granted / rejected| QoS | <....+
| |<-----------------| reservation |
+-------------+ +--------------+
Figure 4: Token-based Three Party Scheme
The 'Token-based Three Party scheme' is applicable to environments
where a previous protocol interaction is used to request
authorization tokens to assist the authorization process at the
Network Element or the Authorizing Entity.
The QoS resource requesting entity may be involved in an application
layer protocol interaction, for example using SIP, with the
Authorizing Entity. As part of this interaction, authentication and
authorization at the application layer might take place. As a result
of a successful authorization decision, which might involve the
user's home AAA server, an authorization token is generated by the
Authorizing Entity (e.g., the SIP proxy and an entity trusted by the
SIP proxy) and returned to the end host for inclusion into the QoS
signaling protocol. The authorization token will be used by a
Network Element that receives the QoS signaling message to authorize
the QoS request. Alternatively, the Diameter QoS application will be
used to forward the authorization token to the user's home network.
The authorization token allows the authorization decision performed
at the application layer protocol run to be associated with a
corresponding QoS signaling session. Note that the authorization
token might either refer to established state concerning the
authorization decision or the token might itself carry the authorized
parameters (protected by a digital signature or a keyed message
digest to prevent tampering). In the latter case the authorization
token may contain several pieces of information pertaining to the
authorized application session, but at minimum it should contain:
o An identifier of the Authorizing Entity (for example, of an
application server) that issued the authorization token,
o An identifier referring to a specific application protocol session
for which the token was issued and
o A keyed message digest or digital signature protecting the content
of the authorization token.
A possible structure for the authorization token and the policy
element carrying it are proposed in context of RSVP [RFC3520].
In the scenario mentioned above, where the QoS resource requesting
entity is involved in an application layer protocol interaction with
the Authorizing entity, it may be worthwhile to consider a token less
binding mechanism also. The application layer protocol interaction
may have indicated the transport port numbers at the QoS resource
requesting entity where it might receive media streams, for example
in SIP/SDP signalling these port numbers are advertised. The QoS
resource requesting entity may also use these port numbers in some IP
filter indications to the NE performing QoS reservation so that it
may properly tunnel the inbound packets. The NE performing QoS
reservation will forward the QoS resource requesting entity's IP
address and the IP filter indications to the Authorizing entity in
the QoS authz. request. The Authorizing entity will use the QoS
resource requesting entity's IP address and the port numbers in the
IP filter indication, which will match the port numbers advertised in
the earlier application layer protocol interaction, to identify the
right piece of policy information to be sent to the NE performing the
QoS reservation in the QoS authz. response.
3.3.2. Authorization schemes for push mode
The push mode can be further divided into two types: endpoint
initiated and network initiated. In the former case, the
authorization process is triggered by application server upon
explicit QoS request from endpoints through application signaling,
e.g. SIP; in the latter case, the authorization process is triggered
by application server without explicit QoS request from endpoint.
In the endpoint initiated scheme, the QoS resource requesting entity
(i.e. endpoint) determines the required application level QoS and
sends the QoS request through application signaling message, the
Application Server will extract application level QoS information and
trigger the authorization process to Authorizing entity. In the
network initiated scheme, the Authorizing entity and/or Application
sever should derive and determine the QoS requirement according to
application attribute, subscription and endpoint's capability when
the endpoint does not explicitly indicate the QoS attributes. The
authorizing entity makes authorization decision based on application
level QoS information, network policies, end user subscription and
network resource availability etc., and installs the decision to
network element directly.
financial settlement
...........................+
Application V ------- .
signaling msg +--------------+ / QoS AAA \ .
+-------------->| | / protocol \ .
| | Authorizing +--------------+ \ .
| | Entity | | | | .
| + |<--+----+ | | .
| +--------------+ |QoS | |QoS |.
| install| |install
| |rsp. | |req. |.
| | | | |.
| | | | . | .
| \ | | . / .
| \ | | / .
V |-----V . .
+-------------+ +--------+-----+ .
| Entity | | NE | .
| requesting | | performing | .
| resource |QoS rsrc granted | QoS | <....+
| |<-----------------| reservation |
+-------------+ +--------------+
Figure 5: Authorization Scheme for Push Mode
3.4. QoS Authorization Requirements
A QoS authorization application must meet a number of requirements
applicable to a diverse set of networking environments and services.
It should be compliant with different deployment scenarios with
specific QoS signaling models and security issues. Satisfying the
requirements listed below while interworking with QoS signaling
protocols, a Diameter QoS application should accommodate the
capabilities of the QoS signaling protocols rather than introducing
functional requirements on them. A list of requirements for a QoS
authorization application is provided here:
Inter-domain support
In particular, users may roam outside their home network, leading
to a situation where the network element and authorizing entity
are in different administrative domains.
Identity-based Routing
The QoS AAA protocol MUST route AAA requests to the Authorizing
Entity, based on the provided identity of the QoS requesting
entity or the identity of the Authorizing entity encoded in the
provided authorization token.
Flexible Authentication Support
The QoS AAA protocol MUST support a variety of different
authentication protocols for verification of authentication
information present in QoS signaling messages. The support for
these protocols MAY be provided indirectly by tying the signaling
communication for QoS to a previous authentication protocol
exchange (e.g., using network access authentication).
Making an Authorization Decision
The QoS AAA protocol MUST exchange sufficient information between
the authorizing entity and the enforcing entity (and vice versa)
to compute an authorization decision and to execute this decision.
Triggering an Authorization Process
The QoS AAA protocol MUST allow periodic and event triggered
execution of the authorization process, originated at the
enforcing entity or even at the authorizing entity.
Associating QoS Reservations and Application State
The QoS AAA protocol MUST carry information sufficient for an
application server to identify the appropriate application session
and associate it with a particular QoS reservation.
Dynamic Authorization
It MUST be possible for the QoS AAA protocol to push updates
towards the network element(s) from authorizing entities.
Bearer Gating
The QoS AAA protocol MUST allow the authorizing entity to gate
(i.e., enable/disable) authorized application flows based on e.g.,
application state transitions.
Accounting Records
The QoS AAA protocol MUST define QoS accounting records containing
duration, volume (byte count) usage information and description of
the QoS attributes (e.g., bandwidth, delay, loss rate) that were
supported for the flow.
Sending Accounting Records
The network element SHOULD send accounting records for a
particular QoS reservation state to the authorizing entity, which
plays the role of an accounting entity.
Failure Notification
The QoS AAA protocol MUST allow the network element to report
failures, such as loss of connectivity due to movement of a mobile
node or other reasons for packet loss, to the authorizing entity.
Accounting Correlation
The QoS AAA protocol MUST support the exchange of sufficient
information to allow for correlation between accounting records
generated by the network elements and accounting records generated
by an application server.
Interaction with other AAA Applications
Interaction with other AAA applications such as Diameter Network
Access (NASREQ) application [RFC4005] is required for exchange of
authorization, authentication and accounting information.
In deployment scenarios, where authentication of the QoS reservation
requesting entity (e.g., the user) is done by means outside the
Diameter QoS application protocol interaction the Authorizing Entity
is contacted only with a request for QoS authorization.
Authentication might have taken place already via the interaction
with the Diameter NASREQ application or as part of the QoS signaling
protocol (e.g., Transport Layer Security (TLS) handshake in the
General Internet Signaling Transport (GIST) protocol, see
[I-D.ietf-nsis-ntlp]).
Authentication of the QoS reservation requesting entity to the
Authorizing Entity is necessary if a particular Diameter QoS
application protocol run cannot be related (or if there is no
intention to relate it) to a prior authentication. In this case the
Authorizing Entity MUST authenticate the QoS reservation requesting
entity in order to authorize the QoS request as part of the Diameter
QoS protocol interaction.
The document refers to three types of sessions that need to be
properly correlated.
QoS signaling session
The time period during which a QoS signaling protocol establishes, Diameter QoS Application Server
maintains and deletes a QoS reservation state at the QoS network
element is referred as QoS signaling session. Different QoS
signaling protocols use different ways to identify QoS signaling
sessions. The same applies to different usage environments.
Currently, this document supports three types of QoS session
identifiers, namely a signaling session id (e.g., the Session
Identifier used by the NSIS protocol suite), a flow id (e.g.,
identifier assigned by an application to a certain flow as used in
the 3GPP) and a flow description based on the IP parameters of the
flow's end points. The details can be found in Section 7.4.
Diameter authorization session A Diameter QoS application server is a logical Diameter node that
supports the protocol interaction for QoS authorization. The
Diameter QoS server resides in the authorizing entity and is able
to respond to a Diameter session received from a Diameter QoS
client, or initiate a Diameter session to a Diameter QoS client
triggered by application signaling or local events.
The time period, for which a Diameter server authorizes a Diameter QoS Application Client
requested service (i.e., QoS resource reservation) is referred to
as a Diameter authorization session. It is identified by a
Session-Id included in all Diameter messages used for management
of the authorized service (initial authorization, re-
authorization, termination), see [RFC3588].
Application layer session A Diameter QoS application client is a logical Diameter node that
supports the protocol interaction for QoS enforcement. The
Diameter QoS client resides in the network element and is able to
initiate a Diameter session triggered by a QoS signaling or other
events, or respond to a Diameter session initiated by a Diameter
QoS server.
The application layer session identifies the duration of an Resource Requesting Entity
application layer service which requires provision of certain QoS.
An application layer session identifier is provided by the QoS
requesting entity in the QoS signaling messages, for example as
part of the authorization token. In general, the application
session identifier is opaque to the QoS aware network elements.
It is included in the authorization request message sent to the
Authorizing entity and helps it to correlate the QoS authorization
request to the application session state information.
Correlating these sessions is done at each of the three involved A resource requesting entity is a logical entity that supports the
entities: The QoS requesting entity correlates the application with protocol interaction for QoS resources. The resource requesting
the QoS signaling sessions. The QoS network element correlates the entity resides in the end-host and is able to communicate with
QoS signaling session with the Diameter authorization sessions. The peer logicial entities in Authorizing Entity or Network element to
Authorizing entity SHOULD bind the information about the three trigger the QoS authorization process.
sessions together. Note that in certain scenarios not all of the
sessions are present. For example, the application session might not
be visible to QoS signaling protocol directly if there is no binding
between the application session and the QoS requesting entity using
the QoS signaling protocol.
4. Diameter QoS Authorization Session Establishment and Management 3. Diameter QoS Authorization Session Establishment and Management
4.1. Parties involved 3.1. Parties involved
Authorization models supported by this application include three Authorization models supported by this application include three
parties: parties:
o Resource requesting entity o Resource requesting entity
o Network Elements (Diameter QoS clients) o Network Elements (Diameter QoS application (DQA) client)
o Authorizing Entity (Diameter QoS server) o Authorizing Entity (Diameter QoS application (DQA) server)
Note that the QoS resource requesting entity is only indirectly Note that the QoS resource requesting entity is only indirectly
involved in the message exchange. This entity provides the trigger involved in the message exchange. This entity provides the trigger
to initiate the Diameter QoS protocol interaction by transmitting QoS to initiate the Diameter QoS protocol interaction by transmitting QoS
signaling messages. The Diameter QoS application is only executed signaling messages. The Diameter QoS application is only executed
between the Network Element (i.e., Diameter QoS client) and the between the Network Element (i.e., DQA client) and the Authorizing
Authorizing Entity (i.e., Diameter QoS server). Entity (i.e., DQA server).
The QoS resource requesting entity may communicate with the The QoS resource requesting entity may communicate with the
Authorizing Entity using application layer signaling for negotiation Authorizing Entity using application layer signaling for negotiation
of service parameters. As part of this application layer protocol of service parameters. As part of this application layer protocol
interaction, for example using SIP, authentication and authorization interaction, for example using SIP, authentication and authorization
might take place. This message exchange is, however, outside the might take place. This message exchange is, however, outside the
scope of this document. The protocol communication between the the scope of this document. The protocol communication between the QoS
QoS resource requesting entity and the QoS Network Element might be resource requesting entity and the QoS Network Element might be
accomplished using the NSIS protocol suite, RSVP or a link layer accomplished using the NSIS protocol suite, RSVP or a link layer
signaling protocol. A description of these protocols is also outside signaling protocol. A description of these protocols is also outside
the scope of this document and a tight coupling with these protocols the scope of this document and a tight coupling with these protocols
is not desirable since this applications aims to be generic. is not desirable since this applications aims to be generic.
4.2. Diameter QoS Authorization Session Establishment 3.2. Diameter QoS Authorization Session Establishment
Figure 7 shows the protocol interaction between a resource requesting The Pull and Push modes use a different set of command codes for
session establishment. For other operations, such as session
modification and termination, they use the same set of command codes.
The Pull mode or Push mode operation is invoked based on the trigger
of QoS Authorization session. When a QAR with a new session ID is
received, the Authorizing Entity operates in the pull mode; when
other triggers are received, the Authorizing Entity operates in the
push mode. Similarly, when a QIR with new session ID is received,
the Network Element operates in the push mode; when other triggers
are recevied, the Network Element operation in the pull mode.
3.2.1. QoS authorization session establishment for pull mode
A request for a QoS reservation or local events received by a Network
Element can trigger the initiation of a Diameter QoS authorization
session. The Network Element generates a QoS-Authorization-Request
(QAR) message in which it maps required objects from the QoS
signaling message to Diameter payload objects.
Figure 2 shows the protocol interaction between a resource requesting
entity, a Network Element and the Authorizing Entity. entity, a Network Element and the Authorizing Entity.
A request for a QoS reservation received by a Network Element The Authorizing Entity's identity, information about the application
initiates a Diameter QoS authorization session. The Network Element session and/or identity and credentials of the QoS resource
generates a QoS-Authorization-Request (QAR) message in which it maps requesting entity, requested QoS parameters, signaling session
required objects from the QoS signaling message to Diameter payload identifier and/or QoS enabled data flows identifiers MAY be
objects. encapsulated into respective Diameter AVPs and included into the
Diameter message sent to the Authorizing Entity. The QAR is sent to
a Diameter server that can either be the home server of the QoS
requesting entity or an application server.
+----------------------------------+-------------------------------+ +----------------------------------+-------------------------------+
| QoS specific Input Data | Diameter QoS AVPs | | QoS specific Input Data | Diameter QoS AVPs |
+----------------------------------+-------------------------------+ +----------------------------------+-------------------------------+
| Authorizing entity ID (e.g., | Destination-Host | | Authorizing entity ID (e.g., | Destination-Host |
| taken from authorization token | Destination-Realm | | taken from authorization token | Destination-Realm |
| or from Network Access ID (NAI) | | | or derived based on Network | |
| [RFC2486] of the QoS requesting | | | Access ID (NAI) [RFC2486] | |
| entity) | | | of the QoS requesting entity) | |
+----------------------------------+-------------------------------+ +----------------------------------+-------------------------------+
| Authorization Token | QoS-Authz-Data | | Authorization Token | QoS-Authz-Data |
| Credentials of | User-Name | | Credentials of | User-Name |
| the QoS requesting entity | | | the QoS requesting entity | |
+----------------------------------+-------------------------------+ +----------------------------------+-------------------------------+
| QoS parameters | QoS-Resources | | QoS parameters | QoS-Resources |
+----------------------------------+-------------------------------+ +----------------------------------+-------------------------------+
The Authorizing Entity's identity, information about the application
session and/or identity and credentials of the QoS resource
requesting entity, requested QoS parameters, signaling session
identifier and/or QoS enabled data flows identifiers MAY be
encapsulated into respective Diameter AVPs and included into the
Diameter message sent to the Authorizing Entity. The QAR is sent to
a Diameter server that can either be the home server of the QoS
requesting entity or an application server.
Authorization processing starts at the Diameter QoS server when it Authorization processing starts at the Diameter QoS server when it
receives the QAR. Based on the information in the QoS- receives the QAR. Based on the information in the QoS-
Authentication-Data, User-Name and QoS-Resources AVPs the server Authentication-Data, User-Name and QoS-Resources AVPs the server
determines the authorized QoS resources and flow state (enabled/ determines the authorized QoS resources and flow state (enabled/
disabled) from locally available information (e.g., policy disabled) from locally available information (e.g., policy
information that may be previously established as part of an information that may be previously established as part of an
application layer signaling exchange, or the user's subscription application layer signaling exchange, or the user's subscription
profile). The authorization decision is then reflected in the profile). The QoS-Resources AVP is defined in
response returned to the Diameter client with the QoS-Authorization- [I-D.ietf-dime-qos-attributes]. The authorization decision is then
Answer message (QAA). reflected in the response returned to the Diameter client with the
QoS-Authorization-Answer message (QAA).
Authorizing Authorizing
End-Host Network Element Entity End-Host Network Element Entity
requesting QoS ( Diameter ( Diameter requesting QoS ( Diameter ( Diameter
QoS Client) QoS Server) QoS Client) QoS Server)
| | | | | |
+---QoS-Reserve---->| | +---QoS-Reserve---->| |
| +- - - - - QAR - - - - - >| | +- - - - - QAR - - - - - >|
| |(QoS-Resources,Cost, | | |(QoS-Resources,Cost, |
| | QoS-Auth-Data,User-ID)| | | QoS-Auth-Data,User-ID)|
skipping to change at page 24, line 48 skipping to change at page 8, line 48
| |CC-Time,Acc-Multisess-id)| | |CC-Time,Acc-Multisess-id)|
| | +--------+--------------+ | | +--------+--------------+
| | | Report for successful | | | | Report for successful |
| | | QoS reservation | | | | QoS reservation |
| | |Update of reserved QoS | | | |Update of reserved QoS |
| | | resources | | | | resources |
| | +--------+--------------+ | | +--------+--------------+
| |< - - - - ACA - - - - - -+ | |< - - - - ACA - - - - - -+
| | | | | |
Figure 7: Initial QoS Request Authorization Figure 2: Initial QoS Request Authorization for pull
The Authorizing Entity keeps authorization session state and SHOULD The Authorizing Entity keeps authorization session state and SHOULD
save additional information for management of the session (e.g., Acc- save additional information for management of the session (e.g., Acc-
Multi-Session-Id, Signaling-Session-Id, authentication data) as part Multi-Session-Id, Signaling-Session-Id, authentication data) as part
of the session state information. A Signaling-session-Id (if of the session state information. A Signaling-session-Id (if
present) SHOULD be used together with the generated Acc-Multi- present) SHOULD be used together with the generated Acc-Multi-
Session-Id AVP (see Section 7.3) for binding the authorization and Session-Id AVP (see Section 6.3) for binding the authorization and
the accounting session information in case of end host mobility the accounting session information in case of end host mobility
(i.e., to correlate the Diameter sessions that are initiated for the (i.e., to correlate the Diameter sessions that are initiated for the
same signaling session from different QoS NE). same signaling session from different QoS NE).
The final result of the authorization request is provided in the The final result of the authorization request is provided in the
Result-Code AVP of the QAA message sent by the Authorizing Entity. Result-Code AVP of the QAA message sent by the Authorizing Entity.
In case of successful authorization (i.e., Result-Code = In case of successful authorization (i.e., Result-Code =
DIAMETER_LIMITED_SUCCESS, (see Section 7.1)), information about the DIAMETER_LIMITED_SUCCESS, (see Section 6.1)), information about the
authorized QoS resources and the status of the authorized flow authorized QoS resources and the status of the authorized flow
(enabled/disabled) is provided in the QoS-Resources AVP of the QAA (enabled/disabled) is provided in the QoS-Resources AVP of the QAA
message. The QoS information provided via the QAA is installed by message. The QoS information provided via the QAA is installed by
the QoS Traffic Control function of the Network Element (see the QoS Traffic Control function of the Network Element. The value
Figure 2). The value DIAMETER_LIMITED_SUCCESS indicates that the DIAMETER_LIMITED_SUCCESS indicates that the Authorizing entity
Authorizing entity expects confirmation via an accounting message for expects confirmation via an accounting message for successful QoS
successful QoS resource reservation and for final reserved QoS resource reservation and for final reserved QoS resources (see
resources (see bellow). below).
One important piece of information returned from the Authorizing One important piece of information returned from the Authorizing
Entity is the authorization lifetime (carried inside the QAA). The Entity is the authorization lifetime (carried inside the QAA). The
authorization lifetime allows the Network Element to determine how authorization lifetime allows the Network Element to determine how
long the authorization decision is valid for this particular QoS long the authorization decision is valid for this particular QoS
reservation. A number of factors may influence the authorized reservation. A number of factors may influence the authorized
session duration, such as the user's subscription plan or currently session duration, such as the user's subscription plan or currently
available credits at the user's account (see Section 5). The available credits at the user's account (see Section 4). The
authorization duration is time-based as specified in [RFC3588]. For authorization duration is time-based as specified in [RFC3588]. For
an extension of the authorization period, a new QoS-Authorization- an extension of the authorization period, a new QoS-Authorization-
Request/Answer message exchange SHOULD be initiated. Further aspects Request/Answer message exchange SHOULD be initiated. Further aspects
of QoS authorization session maintenance is discussed in Section 4.3, of QoS authorization session maintenance is discussed in Section 3.3,
Section 4.5 and Section 5. Section 3.4 and Section 4.
The indication of a successful QoS reservation and activation of the The indication of a successful QoS reservation and activation of the
data flow, is provided by the transmission of an Accounting Request data flow is provided by the transmission of an Accounting Request
(ACR) message, which reports the parameters of the established QoS (ACR) message, which reports the parameters of the established QoS
state: reserved resources, duration of the reservation, state: reserved resources, duration of the reservation,
identification of the QoS enabled flow/QoS signaling session and identification of the QoS enabled flow/QoS signaling session and
accounting parameters. The Diameter QoS server acknowledges the accounting parameters. The Diameter QoS server acknowledges the
reserved QoS resources with the Accounting Answer (ACA) message where reserved QoS resources with the Accounting Answer (ACA) message where
the Result-Code is set to 'DIAMETER_SUCCESS'. Note that the reserved the Result-Code is set to 'DIAMETER_SUCCESS'. Note that the reserved
QoS resources reported in the ACR message MAY be different than those QoS resources reported in the ACR message MAY be different than those
initially authorized with the QAA message, due to the QoS signaling initially authorized with the QAA message, due to the QoS signaling
specific behavior (e.g., receiver-initiated reservations with One- specific behavior (e.g., receiver-initiated reservations with One-
Path-With-Advertisements) or specific process of QoS negotiation Path-With-Advertisements) or specific process of QoS negotiation
along the data path. along the data path.
4.3. QoS authorization session re-authorization 3.2.2. QoS authorization session establishment for push mode
The Diameter QoS server in the Authorizing Entity initiates a
Diameter QoS authorization session upon the request for QoS
reservation triggered by application layer signaling or by local
events, and generates a QoS-Install-Request (QIR) message to Diameter
QoS client in the NE in which it maps required objects to Diameter
payload objects.
Figure 4 shows the protocol interaction between the Authorizing
Entity, a Network Element and a resource requesting entity.
The Network Element's identity, information about the application
session and/or identity and credentials of the QoS resource
requesting entity, requested QoS parameters, signaling session
identifier and/or QoS enabled data flows identifiers MAY be
encapsulated into respective Diameter AVPs and included into the
Diameter message sent from a Diameter QoS server in the Authorizing
Entity to a Diameter QoS client in the NE. This requires that the
Authorizing Entity has knowledge of specific information for
allocating and identifying the Network Element that should be
contacted and the data flow for which the QoS reservation should be
established. This information can be statically configured or
dynamically discovered, see section 3.2.3 for details.
+----------------------------------+-------------------------------+
| QoS specific Input Data | Diameter QoS AVPs |
+----------------------------------+-------------------------------+
| Network Element ID (e.g., from | Destination-Host |
| static configuration | Destination-Realm |
| or dynamically discovered, see | |
| section 3.2.3 for details) | |
+----------------------------------+-------------------------------+
| Authorization Token | QoS-Authz-Data |
| Credentials of | User-Name |
| the QoS requesting entity | |
+----------------------------------+-------------------------------+
| QoS parameters | QoS-Resources |
+----------------------------------+-------------------------------+
Authorization processing starts at the Diameter QoS server when it
receives the request from a resource requesting entity through
application server (e.g. SIP Invite) or the trigger by local events
(e.g. pre-configured timer). Based on the received information the
server determines the authorized QoS resources and flow state
(enabled/disabled) from locally available information (e.g., policy
information that may be previously established as part of an
application layer signaling exchange, or the user's subscription
profile). The authorization decision is then reflected in the QoS-
Install-Request message (QIR) to the Diameter QoS client.
Authorizing
End-Host Network Element Entity
requesting QoS ( Diameter ( Diameter
QoS Client) QoS Server)
| | |
| | |<-- Trigger --
| | +--------+--------------+
| | | Authorize request |
| | | Keep session data |
| | |/Authz-time,Session-Id/|
| | +--------+--------------+
| | |
| |<-- - -- - QIR - - - - - -+
| |(Initial Request,Decision |
| |(QoS-Resources,Authz-time)|
| +-------+---------+
| |Install QoS state|
| | + |
| | Authz. session |
| | /Authz-time, |
| | CC-Time,Cost/ |
| +-------+---------+
| + - - - - QIA - - - - - ->|
| | (Result-Code, |
| | QoS-Resources) |
| | +--------+--------------+
| | | Report for successful |
| | | QoS reservation |
| | |Update of reserved QoS |
| | | resources |
| | +--------+--------------+
| | QoS Responder
| | Node
| | |
|=====================Data Flow==============....===>|
| |
| +- - - - - ACR - - - - - >|
| |(START,QoS-Resources,Cost|
| |CC-Time,Acc-Multisess-id)|
| |< - - - - ACA - - - - - -+
| | |
Figure 4: Initial QoS Request Authorization for push
The Authorizing Entity keeps authorization session state and SHOULD
save additional information for management of the session (e.g., Acc-
Multi-Session-Id, Signaling-Session-Id, authentication data) as part
of the session state information. A Signaling-session-Id (if
present) SHOULD be used together with the generated Acc-Multi-
Session-Id AVP (see Section 6.3) for binding the authorization and
the accounting session information in case of end host mobility
(i.e., to correlate the Diameter sessions that are initiated for the
same signaling session from different QoS NE).
The final result of the authorization decision is provided in the
QoS-Resources AVP of the QIR message sent by the Authorizing Entity.
The QoS information provided via the QIR is installed by the QoS
Traffic Control function of the Network Element. In the case of
successful enforcement, the Result-Code (= DIAMETER_SUCCESS, (see
Section 6.1)) information is provided in the QIA message.
One important piece of information from the Authorizing Entity is the
authorization lifetime (carried inside the QIR). The authorization
lifetime allows the Network Element to determine how long the
authorization decision is valid for this particular QoS reservation.
A number of factors may influence the authorized session duration,
such as the user's subscription plan or currently available credits
at the user's account (see Section 4). The authorization duration is
time-based as specified in [RFC3588]. For an extension of the
authorization period, a new QoS-Install-Request/Answer message or
QoS-Authorization-Request/Answer message exchange SHOULD be
initiated. Further aspects of QoS authorization session maintenance
is discussed in Section 3.3, Section 3.4 and Section 4.
The indication of a successful QoS reservation and activation of the
data flow, is provided by the QoS-Install-Answer message. Note that
the reserved QoS resources reported in the QIA message MAY be
different than those initially authorized with the QIR message, due
to the QoS signaling specific behavior (e.g., receiver-initiated
reservations with One-Path-With-Advertisements) or specific process
of QoS negotiation along the data path.
In case of xxx = Acounting_Info in the QIR, it indicates the
confirmation to an accounting server for successful QoS resource
reservation and for final reserved QoS resources (see below). An ACR
message reports the parameters of the established QoS state: reserved
resources, duration of the reservation, identification of the QoS
enabled flow/QoS signaling session and accounting parameters to
accounting server. The accounting server acknowledges the reserved
QoS resources with the Accounting Answer (ACA) message where the
Result-Code is set to 'DIAMETER_SUCCESS'.
3.2.3. Discovery and selection of peer Diameter QoS application node
The Diameter QoS application node may obtain the location information
of its peer nodes (i.e. FQDN or IP address) through static
configuration or dynamic discovery as described in [RFC3588]. In
particular, the Network Element shall perform the relevant operation
for Pull mode; the Authorizing Entity shall perform the relevant
operations for Push mode.
Upon receipt of a trigger to initiate a new Diameter QoS
authorization session, the Diameter QoS application node selects and
retrieves the location information of the peer node and based on some
index information provided by the resource requesting entity. For
instance, it can be the Authorization Entity's ID stored in the
authorization token, the end-host's identity (e.g. NAI [RFC2486]) or
globally routable IP address.
3.3. QoS authorization session re-authorization
Client and server-side initiated re-authorizations are considered in Client and server-side initiated re-authorizations are considered in
the design of the Diameter QoS application. Whether the re- the design of the Diameter QoS application. Whether the re-
authorization events are transparent for the resource requesting authorization events are transparent for the resource requesting
entity or result in specific actions in the QoS signaling protocol is entity or result in specific actions in the QoS signaling protocol is
outside the scope of the Diameter QoS application. It is directly outside the scope of the Diameter QoS application. It is directly
dependent on the capabilities of the QoS signaling protocol. dependent on the capabilities of the QoS signaling protocol.
In addition, there are a number of options for policy rules according There are a number of options for policy rules according to which the
to which the NE (AAA client) contacts the Authorizing Entity for re- NE (AAA client) contacts the Authorizing Entity for re-authorization.
authorization. These rules depend on the semantics and contents of These rules depend on the semantics and contents of the QAA message
the QAA message sent by the Authorizing Entity: sent by the Authorizing Entity:
a. The QAA message contains the authorized parameters of the flow a. The QAA message contains the authorized parameters of the flow
and its QoS and sets their limits (presumably upper). With these and its QoS and sets their limits (presumably upper). With these
parameters the Authorizing Entity specifies the services that the parameters the Authorizing Entity specifies the services that the
NE can provide and will be financially compensated for. NE can provide and will be financially compensated for.
Therefore, any change or request for change of the parameters of Therefore, any change or request for change of the parameters of
the flow and its QoS that do not conform to the authorized limits the flow and its QoS that do not conform to the authorized limits
requires contacting the Authorizing Entity for authorization. requires contacting the Authorizing Entity for authorization.
b. The QAA message contains authorized parameters of the flow and b. The QAA message contains authorized parameters of the flow and
its QoS. The rules that determine whether parameters' changes its QoS. The rules that determine whether parameters' changes
skipping to change at page 26, line 35 skipping to change at page 14, line 4
requires contacting the Authorizing Entity for authorization. requires contacting the Authorizing Entity for authorization.
b. The QAA message contains authorized parameters of the flow and b. The QAA message contains authorized parameters of the flow and
its QoS. The rules that determine whether parameters' changes its QoS. The rules that determine whether parameters' changes
require re-authorization are agreed out of band, based on a require re-authorization are agreed out of band, based on a
Service Level Agreement (SLA) between the domains of the NE and Service Level Agreement (SLA) between the domains of the NE and
the Authorizing Entity. the Authorizing Entity.
c. The QAA message contains the authorized parameters of the flow c. The QAA message contains the authorized parameters of the flow
and its QoS. Any change or request for change of these and its QoS. Any change or request for change of these
parameters requires contacting the Authorizing entity for re- parameters requires contacting the Authorizing entity for re-
authorization. authorization.
d. In addition to the authorized parameters of the flow and its QoS, d. In addition to the authorized parameters of the flow and its QoS,
the QAA message contains policy rules that determine the NEs the QAA message contains policy rules that determine the NEs
actions in case of change or request for change in authorized actions in case of change or request for change in authorized
parameters. parameters.
Provided options are not exhaustive. Elaborating on any of the Provided options are not exhaustive. Elaborating on any of the
listed approaches is deployment /solution specific and is not listed approaches is deployment /solution specific and is not
considered in the current document. considered in the current document.
4.3.1. Client-Side Initiated Re-Authorization In addition, the Authorizing Entity may use RAR to perform re-
authorization with the authorized parameters directly when the re-
authorization is triggered by service request or local events/policy
rules.
3.3.1. Client-Side Initiated Re-Authorization
The Authorizing Entity provides the duration of the authorization The Authorizing Entity provides the duration of the authorization
session as part of the QoS-Authorization-Answer message (QAA). At session as part of the QoS-Authorization-Answer message (QAA). At
any time before expiration of this period, a new QoS-Authorization- any time before expiration of this period, a new QoS-Authorization-
Request message (QAR) MAY be sent to the Authorizing Entity. The Request message (QAR) MAY be sent to the Authorizing Entity. The
transmission of the QAR MAY be triggered when the Network Element transmission of the QAR MAY be triggered when the Network Element
receives a QoS signaling message that requires modification of the receives a QoS signaling message that requires modification of the
authorized parameters of an ongoing QoS session, when authorization authorized parameters of an ongoing QoS session, when authorization
lifetime expires or by an accounting event, see Section 5 and lifetime expires or by an accounting event, see Section 4 and
Figure 8). Figure 5).
Authorizing Authorizing
End-Host Network Element Entity End-Host Network Element Entity
requesting QoS ( Diameter ( Diameter requesting QoS ( Diameter ( Diameter
QoS Client) QoS Server) QoS Client) QoS Server)
| | | | | |
|=====================Data Flow==========================> |=====================Data Flow==========================>
| | | | | |
| +-------+----------+ | | +-------+----------+ |
| |Authz-time/CC-Time| | | |Authz-time/CC-Time| |
skipping to change at page 27, line 49 skipping to change at page 15, line 47
| |CC-Time,Acc-Multisess-id)| | |CC-Time,Acc-Multisess-id)|
| | +--------+--------------+ | | +--------+--------------+
| | |Update of QoS resources| | | |Update of QoS resources|
| | |/CC-Time,Cost/ used | | | |/CC-Time,Cost/ used |
| | +--------+--------------+ | | +--------+--------------+
| |< - - - - ACA - - - - - -+ | |< - - - - ACA - - - - - -+
| | | | | |
|=====================Data Flow==========================> |=====================Data Flow==========================>
| | | |
Figure 8: QoS request re-authorization Figure 5: Client-side initiated QoS re-authorization
4.3.2. Server-Side Initiated Re-Authorization 3.3.2. Server-Side Initiated Re-Authorization
The Authorizing Entity MAY optionally initiate a QoS re-authorization The Authorizing Entity MAY initiate a QoS re-authorization by issuing
by issuing a Re-Auth-Request message (RAR) as defined in the Diameter a Re-Auth-Request message (RAR) as defined in the Diameter base
base protocol [RFC3588]. A Network Element client that receives such protocol [RFC3588], which may include the parameters of the re-
a RAR message with Session-Id matching a currently active QoS session authorized QoS state: reserved resources, duration of the
acknowledges the request by sending the Re-Auth-Answer (RAA) message reservation, identification of the QoS enabled flow/QoS signaling
and MUST initiate a QoS reservation re-authorization by sending a session for re-installation of the resource state by the QoS Traffic
QoS-Authorization-Request (QAR) message towards the Authorizing Control function of the Network Element.
entity.
4.4. Server-Side Initiated QoS Parameter Provisioning A Network Element that receives such a RAR message with Session-Id
matching a currently active QoS session acknowledges the request by
sending the Re-Auth-Answer (RAA) message towards the Authorizing
entity.
In certain deployment scenarios (mostly applicable for local QoS If RAR does not include any parameters of the re-authorized QoS
provision) an active control over the QoS resource and QoS enabled state, the Network Element MUST initiate a QoS re-authorization by
data flows from the network side is required. Therefore, the sending a QoS-Authorization-Request (QAR) message towards the
Authorizing Entity is enabled to update installed QoS parameters and Authorizing entity.
flow state at the Network Element by sending a QoS-Install Request
message (QIR). Network Elements MUST apply the updates and respond
with an QoS-Install Answer message (QIA). This functionality, for
example, allows the update of already authorized flow status of an
established QoS reservation due to a change at the application layer
session (see Figure 9).
Authorizing Authorizing
End-Host Network Element Entity End-Host Network Element Entity
requesting QoS ( Diameter ( Diameter requesting QoS ( Diameter ( Diameter
QoS Client) QoS Server) QoS Client) QoS Server)
| | | | | |
+===================+=Data Flow==========================> | | |<-- Trigger --
| | +--------+--------------+ | | +--------+--------------+
| | |Data flow preemption | | | | Authorize request |
| | | Keep session data |
| | |/Authz-time,Session-Id/|
| | +--------+--------------+ | | +--------+--------------+
| |< - - - - QIR - - - - - -+ | | |
| |(QoS-Resources[QoS-Flow- | | |<-- - -- - RAR - - - - - -+
| | -State=CLOSE]) | | |(Request,Decision |
| +-------+---------+ | | |(QoS-Resources,Authz-time)|
| |Update QoS state | | | +-------+---------+
| | + | | | |Install QoS state|
| | Authz. session | | | | + |
| |/QoS-Flow-State= | | | | Authz. session |
| | CLOSE/ | | | | /Authz-time, |
| +-------+---------+ | | | CC-Time,Cost/ |
+====Data Flow=====>X | | +-------+---------+
| +- - - - - QIA - - - - - >| | + - - - - RAA - - - - - ->|
| | (Result-Code) | | | (Result-Code, |
Figure 9: Server-Side Initiated QoS Parameter Provisioning | | QoS-Resources) |
| | +--------+--------------+
| | | Report for successful |
| | | QoS reservation |
| | |Update of reserved QoS |
| | | resources |
| | +--------+--------------+
| | |
| +- - - - - ACR - - - - - >|
| |(INTRM,QoS-Resources,Cost|
| |CC-Time,Acc-Multisess-id)|
| | +--------+--------------+
| | |Update of QoS resources|
| | |/CC-Time,Cost/ used |
| | +--------+--------------+
| |< - - - - ACA - - - - - -+
| | |
The Authorizing Entity MAY initiate a QoS authorization session Figure 6: Server-side Initiated QoS re-authorization
establishment and QoS reservation state installation (prior to a
request from a Network Element). This function requires that the
Authorizing Entity has knowledge of specific information identifying
the Network Element that should be contacted and the data flow for
which the QoS reservation should be established.(mostly applicable
for local scenarios)
4.5. Session Termination 3.4. Session Termination
4.5.1. Client-Side Initiated Session Termination 3.4.1. Client-Side Initiated Session Termination
The authorization session for an installed QoS reservation state MAY The authorization session for an installed QoS reservation state MAY
be terminated by the Diameter client by sending a Session- be terminated by the Diameter client by sending a Session-
Termination-Request message (STR) to the Diameter server. This is a Termination-Request message (STR) to the Diameter server. This is a
Diameter base protocol function and it is defined in [RFC3588]. Diameter base protocol function and it is defined in [RFC3588].
Session termination can be caused by a QoS signaling messaging Session termination can be caused by a QoS signaling messaging
requesting deletion of the existing QoS reservation state or it can requesting deletion of the existing QoS reservation state or it can
be caused as a result of a soft-state expiration of the QoS be caused as a result of a soft-state expiration of the QoS
reservation state. After a successful termination of the reservation state. After a successful termination of the
authorization session, final accounting messages MUST be exchanged authorization session, final accounting messages MUST be exchanged
(see Figure 10). It should be noted that the two sessions (see Figure 7). It should be noted that the two sessions
(authorization and accounting) have independent management by the (authorization and accounting) have independent management by the
Diameter base protocol, which allows for finalizing the accounting Diameter base protocol, which allows for finalizing the accounting
session after the end of the authorization session. session after the end of the authorization session.
Authorizing Authorizing
End-Host Network Element Entity End-Host Network Element Entity
requesting QoS ( Diameter ( Diameter requesting QoS ( Diameter ( Diameter
QoS Client) QoS Server) QoS Client) QoS Server)
| | | | | |
|==Data Flow==>X /Stop of the data flow/ | |==Data Flow==>X /Stop of the data flow/ |
skipping to change at page 30, line 42 skipping to change at page 19, line 42
| | Report for successful | | | Report for successful |
| | end of QoS session | | | end of QoS session |
| +--------+--------------+ | +--------+--------------+
|< - - - - ACA - - - - - -+ |< - - - - ACA - - - - - -+
| |
| QoS Responder | QoS Responder
| Node | Node
|<---------QoS-Response----....----+ |<---------QoS-Response----....----+
| | | |
Figure 10: Client-Side Initiated Session Termination Figure 7: Client-Side Initiated Session Termination
4.5.2. Server-Side Initiated Session Termination 3.4.2. Server-Side Initiated Session Termination
At anytime during a session the Authorizing Entity MAY send an Abort- At anytime during a session the Authorizing Entity MAY send an Abort-
Session-Request message (ASR) to the Network Element. This is a Session-Request message (ASR) to the Network Element. This is a
Diameter base protocol function and it is defined in [RFC3588]. Diameter base protocol function and it is defined in [RFC3588].
Possible reasons for initiating the ASR message to the Network Possible reasons for initiating the ASR message to the Network
Element are insufficient credits or session termination at the Element are insufficient credits or session termination at the
application layer. The ASR message results in termination of the application layer. The ASR message results in termination of the
authorized session, release of the reserved resources at the Network authorized session, release of the reserved resources at the Network
Element and transmission of an appropriate QoS signaling message Element and transmission of an appropriate QoS signaling message
indicating a notification to other Network Elements aware of the indicating a notification to other Network Elements aware of the
signaling session. A final accounting message exchange MUST be signaling session. A final accounting message exchange MUST be
triggered as a result of this ASR message exchange (see Figure 11). triggered as a result of this ASR message exchange (see Figure 8).
Authorizing Authorizing
End-Host Network Element Entity End-Host Network Element Entity
requesting QoS ( Diameter ( Diameter requesting QoS ( Diameter ( Diameter
QoS Client) QoS Server) QoS Client) QoS Server)
| | | | | |
|=====================Data Flow==========================> |=====================Data Flow==========================>
| | | |
| |< - - - - ASR - - - - - -+ | |< - - - - ASR - - - - - -+
| | | | | |
skipping to change at page 31, line 46 skipping to change at page 20, line 46
| +--------+--------------+ | +--------+--------------+
| | Report for successful | | | Report for successful |
| | end of QoS session | | | end of QoS session |
| +--------+--------------+ | +--------+--------------+
|< - - - - ACA - - - - - -+ |< - - - - ACA - - - - - -+
| QoS Responder | QoS Responder
| Node | Node
|<---------QoS-Response----....----+ |<---------QoS-Response----....----+
| | | |
Figure 11: Server-Side Initiated Session Termination Figure 8: Server-Side Initiated Session Termination
5. Accounting 4. Accounting
The Diameter QoS application provides accounting for usage of The Diameter QoS application provides accounting for usage of
reserved QoS resources. Diameter QoS accounting has built-in support reserved QoS resources. Diameter QoS accounting has built-in support
for online, duration based accounting. This accounting is based on for online, duration based accounting. This accounting is based on
the notion that the Diameter QoS clients are in the best position to the notion that the Diameter QoS clients are in the best position to
determine the cost of those resources. determine the cost of those resources.
In the Diameter QoS application, the router MAY send a Cost- In the Diameter QoS application, the router MAY send a Cost-
Information AVP (see [RFC4006]) in the QAR. If the Cost-Information Information AVP (see [RFC4006]) in the QAR. If the Cost-Information
AVP includes a Cost-Unit AVP (see [RFC4006]) then the Cost-Unit AVP includes a Cost-Unit AVP (see [RFC4006]) then the Cost-Unit
skipping to change at page 32, line 41 skipping to change at page 21, line 41
in the Cost-Information AVPs, the Resource Authorizing Entity can use in the Cost-Information AVPs, the Resource Authorizing Entity can use
the CC-Time AVP to guarantee that the total cost of the session will the CC-Time AVP to guarantee that the total cost of the session will
not exceed a certain threshold, which allows, for example, support of not exceed a certain threshold, which allows, for example, support of
prepaid users. prepaid users.
Each ACR message contains a triplet of QoS-Resources AVP, Cost- Each ACR message contains a triplet of QoS-Resources AVP, Cost-
Information AVP, and CC-Time AVP. This represents the total time Information AVP, and CC-Time AVP. This represents the total time
consumed at the given cost for the given resources. Note that an ACR consumed at the given cost for the given resources. Note that an ACR
message MUST be sent separately for each interval defined by the message MUST be sent separately for each interval defined by the
Tariff-Time-Change AVPs and the expiration of the CC-Time returned in Tariff-Time-Change AVPs and the expiration of the CC-Time returned in
the QAA (see Figure 8). the QAA (see Figure 5).
The Network Element starts an accounting session by sending an The Network Element starts an accounting session by sending an
Accounting-Request message (ACR) after successful QoS reservation and Accounting-Request message (ACR) after successful QoS reservation and
activation of the data flow (see Figure 7). After every successful activation of the data flow (see Figure 2). After every successful
re-authorization procedure the Network element MUST initiate an re-authorization procedure the Network element MUST initiate an
interim accounting message exchange (see Figure 8). After successful interim accounting message exchange (see Figure 5). After successful
session termination the Network element MUST initiate a final session termination the Network element MUST initiate a final
exchange of accounting messages for terminating of the accounting exchange of accounting messages for terminating of the accounting
session and reporting final records for the usage of the QoS session and reporting final records for the usage of the QoS
resources reserved (see Figure 10). resources reserved (see Figure 7).
6. Diameter QoS Authorization Application Messages 5. Diameter QoS Authorization Application Messages
The Diameter QoS Application requires the definition of new mandatory The Diameter QoS Application requires the definition of new mandatory
AVPs and Command-codes (see Section 3 of [RFC3588]). Four new AVPs and Command-codes (see Section 3 of [RFC3588]). Four new
Diameter messages are defined along with Command-Codes whose values Diameter messages are defined along with Command-Codes whose values
MUST be supported by all Diameter implementations that conform to MUST be supported by all Diameter implementations that conform to
this specification. this specification.
Command-Name Abbrev. Code Reference Command-Name Abbrev. Code Reference
QoS-Authz-Request QAR [TBD] Section 6.1 QoS-Authz-Request QAR [TBD] Section 5.1
QoS-Authz-Answer QAA [TBD] Section 6.2 QoS-Authz-Answer QAA [TBD] Section 5.2
QoS-Install-Request QIR [TBD] Section 6.3 QoS-Install-Request QIR [TBD] Section 5.3
QoS-Install-Answer QIA [TBD] Section 6.4 QoS-Install-Answer QIA [TBD] Section 5.4
In addition, the following Diameter Base protocol messages are used In addition, the following Diameter Base protocol messages are used
in the Diameter QoS application: in the Diameter QoS application:
Command-Name Abbrev. Code Reference Command-Name Abbrev. Code Reference
Accounting-Request ACR 271 RFC 3588 Accounting-Request ACR 271 RFC 3588
Accounting-Request ACR 271 RFC 3588 Accounting-Request ACR 271 RFC 3588
Accounting-Answer ACA 271 RFC 3588 Accounting-Answer ACA 271 RFC 3588
Re-Auth-Request RAR 258 RFC 3588 Re-Auth-Request RAR 258 RFC 3588
Re-Auth-Answer RAA 258 RFC 3588 Re-Auth-Answer RAA 258 RFC 3588
skipping to change at page 34, line 5 skipping to change at page 23, line 5
The value of TBD MUST be used as the Application-Id in all ACR/ACA The value of TBD MUST be used as the Application-Id in all ACR/ACA
commands, because this application defines new, mandatory AVPs for commands, because this application defines new, mandatory AVPs for
accounting. accounting.
The value of zero (0) SHOULD be used as the Application-Id in all The value of zero (0) SHOULD be used as the Application-Id in all
STR/STA, ASR/ASA, and RAR/RAA commands, because these commands are STR/STA, ASR/ASA, and RAR/RAA commands, because these commands are
defined in the Diameter base protocol and no additional mandatory defined in the Diameter base protocol and no additional mandatory
AVPs for those commands are defined in this document. AVPs for those commands are defined in this document.
6.1. QoS-Authorization Request (QAR) 5.1. QoS-Authorization Request (QAR)
The QoS-Authorization-Request message (QAR) indicated by the Command- The QoS-Authorization-Request message (QAR) indicated by the Command-
Code field (see Section 3 of [RFC3588]) set to TBD and 'R' bit set in Code field (see Section 3 of [RFC3588]) set to TBD and 'R' bit set in
the Command Flags field is used by Network elements to request the Command Flags field is used by Network elements to request
quality of service related resource authorization for a given flow. quality of service related resource authorization for a given flow.
The QAR message MUST carry information for signaling session The QAR message MUST carry information for signaling session
identification, Authorizing Entity identification, information about identification, Authorizing Entity identification, information about
the requested QoS, and the identity of the QoS requesting entity. In the requested QoS, and the identity of the QoS requesting entity. In
addition, depending on the deployment scenario, an authorization addition, depending on the deployment scenario, an authorization
skipping to change at page 34, line 38 skipping to change at page 23, line 38
{ Auth-Request-Type } { Auth-Request-Type }
[ Destination-Host ] [ Destination-Host ]
[ User-Name ] [ User-Name ]
* [ QoS-Resources ] * [ QoS-Resources ]
[ QoS-Authz-Data ] [ QoS-Authz-Data ]
[ Cost-Information ] [ Cost-Information ]
[ Acc-Multisession-Id ] [ Acc-Multisession-Id ]
[ Bound-Auth-Session-Id ] [ Bound-Auth-Session-Id ]
* [ AVP ] * [ AVP ]
6.2. QoS-Authorization Answer (QAA) 5.2. QoS-Authorization Answer (QAA)
The QoS-Authorization-Answer message (QAA), indicated by the Command- The QoS-Authorization-Answer message (QAA), indicated by the Command-
Code field set to TBD and 'R' bit cleared in the Command Flags field Code field set to TBD and 'R' bit cleared in the Command Flags field
is sent in response to the QoS-Authorization-Request message (QAR). is sent in response to the QoS-Authorization-Request message (QAR).
If the QoS authorization request is successfully authorized, the If the QoS authorization request is successfully authorized, the
response will include the AVPs to allow authorization of the QoS response will include the AVPs to allow authorization of the QoS
resources as well as accounting and transport plane gating resources as well as accounting and transport plane gating
information. information.
The message format is defined as follows: The message format is defined as follows:
skipping to change at page 35, line 20 skipping to change at page 24, line 20
{ Origin-Host } { Origin-Host }
{ Origin-Realm } { Origin-Realm }
* [ QoS-Resources ] * [ QoS-Resources ]
[ CC-Time ] [ CC-Time ]
[ Acc-Multisession-Id ] [ Acc-Multisession-Id ]
[ Session-Timeout ] [ Session-Timeout ]
[ Authz-Session-Lifetime ] [ Authz-Session-Lifetime ]
[ Authz-Grace-Period ] [ Authz-Grace-Period ]
* [ AVP ] * [ AVP ]
6.3. QoS-Install Request (QIR) 5.3. QoS-Install Request (QIR)
The QoS-Install Request message (QIR), indicated by the Command-Code The QoS-Install Request message (QIR), indicated by the Command-Code
field set to TDB and 'R' bit set in the Command Flags field is used field set to TDB and 'R' bit set in the Command Flags field is used
by Authorizing entity to install or update the QoS parameters and the by Authorizing entity to install or update the QoS parameters and the
flow state of an authorized flow at the transport plane element. flow state of an authorized flow at the transport plane element.
The message MUST carry information for signaling session The message MUST carry information for signaling session
identification or identification of the flow to which the provided identification or identification of the flow to which the provided
QoS rules apply, identity of the transport plane element, description QoS rules apply, identity of the transport plane element, description
of provided QoS parameters, flow state and duration of the provided of provided QoS parameters, flow state and duration of the provided
skipping to change at page 36, line 5 skipping to change at page 25, line 5
{ Destination-Realm } { Destination-Realm }
{ Auth-Request-Type } { Auth-Request-Type }
[ Destination-Host ] [ Destination-Host ]
* [ QoS-Resources ] * [ QoS-Resources ]
[ Session-Timeout ] [ Session-Timeout ]
[ Authz-Session-Lifetime ] [ Authz-Session-Lifetime ]
[ Authz-Grace-Period ] [ Authz-Grace-Period ]
[ Authz-Session-Volume ] [ Authz-Session-Volume ]
* [ AVP ] * [ AVP ]
6.4. QoS-Install Answer (QIA) 5.4. QoS-Install Answer (QIA)
The QoS-Install Answer message (QIA), indicated by the Command-Code The QoS-Install Answer message (QIA), indicated by the Command-Code
field set to TBD and 'R' bit cleared in the Command Flags field is field set to TBD and 'R' bit cleared in the Command Flags field is
sent in response to the QoS-Install Request message (QIR) for sent in response to the QoS-Install Request message (QIR) for
confirmation of the result of the installation of the provided QoS confirmation of the result of the installation of the provided QoS
reservation instructions. reservation instructions.
The message format is defined as follows: The message format is defined as follows:
<QoS-Install-Answer> ::= < Diameter Header: XXX, PXY > <QoS-Install-Answer> ::= < Diameter Header: XXX, PXY >
< Session-Id > < Session-Id >
{ Auth-Application-Id } { Auth-Application-Id }
{ Origin-Host } { Origin-Host }
{ Origin-Realm } { Origin-Realm }
{ Result-Code } { Result-Code }
* [ QoS-Resources ] * [ QoS-Resources ]
* [ AVP ] * [ AVP ]
6.5. Accounting Request (ACR) 5.5. Re-Auth-Request (RAR)
The Re-Auth-Request message (RAR), indicated by the Command-Code
field set to 258 and the 'R' bit set in the Command Flags field, is
sent by the Authorizing Entity to the Network Element in order to
initiate the QoS re-authorization from DQA server side.
If the RAR command is received by the Network Element without any
parameters of the re-authorized QoS state, the Network Element MUST
initiate a QoS re-authorization by sending a QoS-Authorization-
Request (QAR) message towards the Authorizing entity.
The message format is defined as follows:
<Re-Auth-Request> ::= < Diameter Header: 258, REQ, PXY >
< Session-Id >
{ Auth-Application-Id }
{ Origin-Host }
{ Origin-Realm }
{ Destination-Realm }
{ Auth-Request-Type }
[ Destination-Host ]
* [ QoS-Resources ]
[ Session-Timeout ]
[ Authz-Session-Lifetime ]
[ Authz-Grace-Period ]
[ Authz-Session-Volume ]
* [ AVP ]
5.6. Re-Auth-Answer (RAA)
The Re-Auth-Answer message (RAA), indicated by the Command-Code field
set to 258 and the 'R' bit cleared in the Command Flags field, is
sent by the Network Element to the Authorizing Entity in response to
the RAR command..
The message format is defined as follows:
<Re-Auth-Answer> ::= < Diameter Header: 258, PXY >
< Session-Id >
{ Auth-Application-Id }
{ Origin-Host }
{ Origin-Realm }
{ Result-Code }
* [ QoS-Resources ]
* [ AVP ]
5.7. Accounting Request (ACR)
The Accounting Request message (ACR), indicated by the Command-Code The Accounting Request message (ACR), indicated by the Command-Code
field set to 271 and 'R' bit set in the Command Flags field is used field set to 271 and 'R' bit set in the Command Flags field is used
by Network Element to report parameters of the authorized and by Network Element to report parameters of the authorized and
established QoS reservation. established QoS reservation.
The message MUST carry accounting information authorized QoS The message MUST carry accounting information authorized QoS
resources and its usage, e.g., QoS-Resources, CC-Time, CC-Cost, Acc- resources and its usage, e.g., QoS-Resources, CC-Time, CC-Cost, Acc-
Multi-Session-Id. Multi-Session-Id.
skipping to change at page 37, line 5 skipping to change at page 27, line 5
{ Destination-Realm } { Destination-Realm }
[ Destination-Host ] [ Destination-Host ]
[ Accounting-Record-Type ] [ Accounting-Record-Type ]
[ Accounting-Record-Number ] [ Accounting-Record-Number ]
* [ QoS-Resources ] * [ QoS-Resources ]
[ Cost-Information ] [ Cost-Information ]
[ CC-Time ] [ CC-Time ]
[ Acc-Multi-Session-Id ] [ Acc-Multi-Session-Id ]
* [ AVP ] * [ AVP ]
6.6. Accounting Answer (ACA) 5.8. Accounting Answer (ACA)
The Accounting Answer message (ACA), indicated by the Command-Code The Accounting Answer message (ACA), indicated by the Command-Code
field set to 271 and 'R' bit cleared in the Command Flags field is field set to 271 and 'R' bit cleared in the Command Flags field is
sent in response to the Accounting Request message (ACR) as an sent in response to the Accounting Request message (ACR) as an
acknowledgment of the ACR message and MAY carry additional management acknowledgment of the ACR message and MAY carry additional management
information for the accounting session, e.g. Acc-Interim-Interval information for the accounting session, e.g. Acc-Interim-Interval
AVP. AVP.
The message format is defined as follows: The message format is defined as follows:
<Accounting-Answer> ::= < Diameter Header: XXX, PXY > <Accounting-Answer> ::= < Diameter Header: XXX, PXY >
< Session-Id > < Session-Id >
{ Acct-Application-Id } { Acct-Application-Id }
[ Result-Code ] [ Result-Code ]
[ Accounting-Record-Type ] [ Accounting-Record-Type ]
[ Accounting-Record-Number ] [ Accounting-Record-Number ]
[ Acc-Multi-Session-Id ] [ Acc-Multi-Session-Id ]
* [ AVP ] * [ AVP ]
7. Diameter QoS Authorization Application AVPs 6. Diameter QoS Authorization Application AVPs
Each of the AVPs identified in the QoS-Authorization-Request/Answer Each of the AVPs identified in the QoS-Authorization-Request/Answer
and QoS-Install-Request/Answer messages and the assignment of their and QoS-Install-Request/Answer messages and the assignment of their
value(s) is given in this section. value(s) is given in this section.
7.1. Diameter Base Protocol AVPs 6.1. Diameter Base Protocol AVPs
The Diameter QoS application uses a number of session management The Diameter QoS application uses a number of session management
AVPs, defined in the Base Protocol ([RFC3588]). AVPs, defined in the Base Protocol ([RFC3588]).
Attribute Name AVP Code Reference [RFC3588] Attribute Name AVP Code Reference [RFC3588]
Origin-Host 264 Section 6.3 Origin-Host 264 Section 6.3
Origin-Realm 296 Section 6.4 Origin-Realm 296 Section 6.4
Destination-Host 293 Section 6.5 Destination-Host 293 Section 6.5
Destination-Realm 283 Section 6.6 Destination-Realm 283 Section 6.6
Auth-Application-Id 258 Section 6.8 Auth-Application-Id 258 Section 6.8
skipping to change at page 38, line 34 skipping to change at page 28, line 34
Session-Id 263 Section 8.8 Session-Id 263 Section 8.8
Authz-Lifetime 291 Section 8.9 Authz-Lifetime 291 Section 8.9
Authz-Grace-Period 276 Section 8.10 Authz-Grace-Period 276 Section 8.10
Session-Timeout 27 Section 8.13 Session-Timeout 27 Section 8.13
User-Name 1 Section 8.14 User-Name 1 Section 8.14
The Auth-Application-Id AVP (AVP Code 258) is assigned by IANA to The Auth-Application-Id AVP (AVP Code 258) is assigned by IANA to
Diameter applications. The value of the Auth-Application-Id for the Diameter applications. The value of the Auth-Application-Id for the
Diameter QoS application is TBD. Diameter QoS application is TBD.
7.2. Credit Control Application AVPs 6.2. Credit Control Application AVPs
The Diameter QoS application provides accounting for usage of The Diameter QoS application provides accounting for usage of
reserved QoS resources. Diameter QoS accounting has built-in support reserved QoS resources. Diameter QoS accounting has built-in support
for online, duration based accounting. For this purpose it re-uses a for online, duration based accounting. For this purpose it re-uses a
number of AVPs defined in Diameter Credit Control application. number of AVPs defined in Diameter Credit Control application.
[RFC4006]. [RFC4006].
Attribute Name AVP Code Reference [RFC4006] Attribute Name AVP Code Reference [RFC4006]
Cost-Information AVP 423 Section 8.7 Cost-Information AVP 423 Section 8.7
Unit-Value AVP 445 Section 8.8 Unit-Value AVP 445 Section 8.8
Currency-Code AVP 425 Section 8.11 Currency-Code AVP 425 Section 8.11
Cost-Unit AVP 424 Section 8.12 Cost-Unit AVP 424 Section 8.12
CC-Time AVP 420 Section 8.21 CC-Time AVP 420 Section 8.21
Tariff-Time-Change AVP 451 Section 6.20 Tariff-Time-Change AVP 451 Section 6.20
Usage of the listed AVPs is described in Section 5 Usage of the listed AVPs is described in Section 4
Diameter QoS application is designed to independently provide credit Diameter QoS application is designed to independently provide credit
control over the controlled QoS resources. However, deployment control over the controlled QoS resources. However, deployment
scenarios, where Diameter QoS application is collocated with Diameter scenarios, where Diameter QoS application is collocated with Diameter
Credit Control application, are not excluded. In such scenarios the Credit Control application, are not excluded. In such scenarios the
credit control over the QoS resources might be managed by the Credit credit control over the QoS resources might be managed by the Credit
control application. Possible interworking approach might be a usage control application. Possible interworking approach might be a usage
of Credit-Control AVP (AVP Code 426) with a newly defined value. It of Credit-Control AVP (AVP Code 426) with a newly defined value. It
will indicate to the Diameter QoS entities that the credit control will indicate to the Diameter QoS entities that the credit control
over the QoS resources would be handled in separate session by Credit over the QoS resources would be handled in separate session by Credit
Control application. An active cooperation of both applications Control application. An active cooperation of both applications
would be required but it is not elaborated further in this document. would be required but it is not elaborated further in this document.
7.3. Accounting AVPs 6.3. Accounting AVPs
The Diameter QoS application uses Diameter Accounting and accounting The Diameter QoS application uses Diameter Accounting and accounting
AVPs as defined in Section 9 of [RFC3588]. Additional description of AVPs as defined in Section 9 of [RFC3588]. Additional description of
the usage of some of them in the QoS authorization context is the usage of some of them in the QoS authorization context is
provided: provided:
Attribute Name AVP Code Reference [RFC3588] Attribute Name AVP Code Reference [RFC3588]
Acct-Application-Id 259 Section 6.9 Acct-Application-Id 259 Section 6.9
Accounting-Record-Type 480 Section 9.8.1 Accounting-Record-Type 480 Section 9.8.1
Accounting-Interim-Interval 85 Section 9.8.2 Accounting-Interim-Interval 85 Section 9.8.2
skipping to change at page 39, line 47 skipping to change at page 29, line 47
the Diameter QoS application is TBD (TBD). the Diameter QoS application is TBD (TBD).
Acc-Multisession-ID Acc-Multisession-ID
Acc-Multi-Session-ID AVP (AVP Code 50) SHOULD be used to link Acc-Multi-Session-ID AVP (AVP Code 50) SHOULD be used to link
multiple accounting sessions together, allowing the correlation of multiple accounting sessions together, allowing the correlation of
accounting information. This AVP MAY be returned by the Diameter accounting information. This AVP MAY be returned by the Diameter
server in a QoS-Authorization-Answer message (QAA), and MUST be server in a QoS-Authorization-Answer message (QAA), and MUST be
used in all accounting messages for the given session. used in all accounting messages for the given session.
7.4. Diameter QoS Application Defined AVPs 6.4. Diameter QoS Application Defined AVPs
This document reuses the AVPs defined in Section 4 of This document reuses the AVPs defined in Section 4 of
[I-D.ietf-dime-qos-attributes]. [I-D.ietf-dime-qos-attributes].
This section lists the AVPs that are used by this specifispecific to This section lists the AVPs that are introduced specifically for the
the Diameter QoS application. Diameter QoS application. The followig new AVPs are defined: Bound-
Auth-Session-Id and the QoS-Authz-Data AVP.
Additionally, the followig new AVPs are defined:
Bound-Auth-Session-Id and the QoS-Authz-Data AVP
The following table describes the Diameter AVPs newly defined in this The following table describes the Diameter AVPs newly defined in this
document for usage with the QoS Application, their AVP code values, document for usage with the QoS Application, their AVP code values,
types, possible flag values, and whether the AVP may be encrypted. types, possible flag values, and whether the AVP may be encrypted.
+-------------------+ +-------------------+
| AVP Flag rules | | AVP Flag rules |
+----------------------------------------------|----+---+----+-----+ +----------------------------------------------|----+---+----+-----+
| AVP Section | | |SHLD| MUST| | AVP Section | | |SHLD| MUST|
| Attribute Name Code Defined Data Type |MUST|MAY| NOT| NOT| | Attribute Name Code Defined Data Type |MUST|MAY| NOT| NOT|
+----------------------------------------------+----+---+----+-----+ +----------------------------------------------+----+---+----+-----+
|QoS-Authz-Data TBD 7.4 Grouped | M | P | | V | |QoS-Authz-Data TBD 6.4 Grouped | M | P | | V |
|Bound-Auth-Session-Id TBD 7.4 UTF8String | M | P | | V | |Bound-Auth-Session-Id TBD 6.4 UTF8String | M | P | | V |
+----------------------------------------------+----+---+----+-----+ +----------------------------------------------+----+---+----+-----+
|M - Mandatory bit. An AVP with "M" bit set and its value MUST be | |M - Mandatory bit. An AVP with "M" bit set and its value MUST be |
| supported and recognized by a Diameter entity in order the | | supported and recognized by a Diameter entity in order the |
| message, which carries this AVP, to be accepted. | | message, which carries this AVP, to be accepted. |
|P - Indicates the need for encryption for end-to-end security. | |P - Indicates the need for encryption for end-to-end security. |
|V - Vendor specific bit that indicates whether the AVP belongs to | |V - Vendor specific bit that indicates whether the AVP belongs to |
| a address space. | | a address space. |
+------------------------------------------------------------------+ +------------------------------------------------------------------+
QoS-Authz-Data QoS-Authz-Data
skipping to change at page 41, line 5 skipping to change at page 31, line 5
Bound-Authentication-Session-Id Bound-Authentication-Session-Id
The Bound-Authentication-Session AVP (AVP Code TBD) is of type The Bound-Authentication-Session AVP (AVP Code TBD) is of type
UTF8String. It carries the id of the Diameter authentication UTF8String. It carries the id of the Diameter authentication
session that is used for the network access authentication (NASREQ session that is used for the network access authentication (NASREQ
authentication session). It is used to tie the QoS authorization authentication session). It is used to tie the QoS authorization
request to a prior authentication of the end host done by a co- request to a prior authentication of the end host done by a co-
located application for network access authentication (Diameter located application for network access authentication (Diameter
NASREQ) at the QoS NE. NASREQ) at the QoS NE.
8. Examples 7. Examples
This section presents an example of the interaction between the 7.1. Example call flow for pull mode
application layer signaling and the QoS signaling along the data
path. The application layer signaling is, in this example, provided This section presents an example of the interaction between the end
using SIP. Signaling for a QoS resource reservation is done using host and Diameter QoS application entities using Pull mode. The
the QoS NSLP. The authorization of the QoS reservation request is application layer signaling is, in this example, provided using SIP.
done by the Diameter QoS application (DQA). Signaling for a QoS resource reservation is done using the QoS NSLP.
The authorization of the QoS reservation request is done by the
Diameter QoS application (DQA).
End-Host SIP Server Correspondent End-Host SIP Server Correspondent
requesting QoS (DQA Server) Node requesting QoS (DQA Server) Node
| | | | | |
..|....Application layer SIP signaling.......|..............|.. ..|....Application layer SIP signaling.......|..............|..
. | Invite (SDP) | | . . | Invite (SDP) | | .
. +.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-> | . . +.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-> | .
. | 100 Trying | | . . | 100 Trying | | .
. <.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-+ Invite (SDP)| . . <.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-+ Invite (SDP)| .
skipping to change at page 42, line 44 skipping to change at page 32, line 45
| | | | | |
/------------------+--Data Flow---------------------------\ /------------------+--Data Flow---------------------------\
\------------------+--------------------------------------/ \------------------+--------------------------------------/
| | | | | |
.-.-.-.-. SIP signaling .-.-.-.-. SIP signaling
--------- QoS NSLP signaling --------- QoS NSLP signaling
- - - - - Diameter QoS Application messages - - - - - Diameter QoS Application messages
========= Mapping of objects between QoS and AAA protocol ========= Mapping of objects between QoS and AAA protocol
Figure 24: Token-based QoS Authorization Example Figure 23: QoS Authorization Example - Pull Mode
The communication starts with SIP signaling between the two end The communication starts with SIP signaling between the two end
points and the SIP server for negotiation and authorization of the points and the SIP server for negotiation and authorization of the
requested service and its parameters (see Figure 24). As a part of requested service and its parameters (see Figure 23). As a part of
the process, the SIP server verifies whether the user at Host A is the process, the SIP server verifies whether the user at Host A is
authorized to use the requested service (and potentially the ability authorized to use the requested service (and potentially the ability
to be charged for the service usage). Negotiated session parameters to be charged for the service usage). Negotiated session parameters
are provided to the end host. are provided to the end host.
Subsequently, Host A initiates a QoS signaling message towards Host Subsequently, Host A initiates a QoS signaling message towards Host
B. It sends a QoS NSLP Reserve message, in which it includes B. It sends a QoS NSLP Reserve message, in which it includes
description of the required QoS (QSPEC object) and authorization data description of the required QoS (QSPEC object) and authorization data
for negotiated service session (part of the POLICY_DATA object). for negotiated service session (part of the POLICY_DATA object).
Authorization data includes, as a minimum, the identity of the Authorization data includes, as a minimum, the identity of the
skipping to change at page 43, line 41 skipping to change at page 33, line 42
replies with QoS-Authorization answer (QAA) message. It carries the replies with QoS-Authorization answer (QAA) message. It carries the
authorization result (Result-Code AVP) and the description of the authorization result (Result-Code AVP) and the description of the
authorized QoS parameters (QoS-Resources AVP), as well as duration of authorized QoS parameters (QoS-Resources AVP), as well as duration of
the authorization session (Authorization-Lifetime AVP) and duration the authorization session (Authorization-Lifetime AVP) and duration
of the time (CC-Time) for which the end-user should be charged with of the time (CC-Time) for which the end-user should be charged with
the rate announced in the QAR message. The NE interacts with the the rate announced in the QAR message. The NE interacts with the
traffic control function and installs the authorized QoS resources traffic control function and installs the authorized QoS resources
and forwards the QoS NSLP Reserve message further along the data and forwards the QoS NSLP Reserve message further along the data
path. path.
Note that the example above shows a sender-initiated reservation from 7.2. Example call flow for push mode
the End-Host towards the corresponding node and a receiver-initiated
reservation from the correspondent node towards the End-Host.
9. IANA Considerations This section presents an example of the interaction between the end-
host and Diameter QoS application entities using Push Mode. The
application layer signaling is, in this example, provided using SIP.
Signaling for a QoS resource reservation is done using the QoS NSLP.
The authorization of the QoS reservation request is done by the
Diameter QoS application (DQA).
TBD End-Host NE SIP Server Correspondent
requesting QoS (DQA Client) (DQA Server) Node
10. Security Considerations | | | |
..|....Application layer SIP signaling..........|..............|..
. | Invite(SDP offer)| | | .
. +.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.> | .
. | 100 Trying | | | .
. <.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.+ | .
. |.............................................|..............| .
| | +---------+-------------+|
| | | Authorize request ||
| | | Keep session data ||
| | |/Authz-time,Session-Id/||
| | +---------+-------------+|
| | | |
| |<-- - -- - QIR - -- - -- -+ |
| |(Initial Request,Decision | |
| |(QoS-Resources,Authz-time)| |
| +-------+---------+ | |
| |Install QoS state| | |
| | + | | |
| | Authz. session | | |
| | /Authz-time, | | |
| | CC-Time,Cost/ | | |
| +-------+---------+ | |
| + - - -- - QIA - - - - - ->| |
| | (Result-Code, | |
| | QoS-Resources) | |
| | +----------+------------+ |
| | | Report for successful | |
| | | QoS reservation | |
| | |Update of reserved QoS | |
| | | resources | |
| | +----------+------------+ |
. | | | Invite (SDP) | .
. | | +-.-.-.....-.-.> .
. | 180 (Ringing) | | .
. <.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.<.-.-.-.-.-.-.-+ .
. | | | 200 OK (SDP)| .
. | | <-.-.-.....-.-.+ .
| | +--------+-----------+ |
| | |re-Authorize session| |
| | | parameters | |
| | +--------+-----------+ |
| <- - - - - - RAR - - - - - + |
| +---------+--------+ | |
| |Activate QoS state| | |
| +---------+--------+ | |
| +- - - - - - RAA - - - - - > |
. | 200 (SDP answer) | | | .
. <.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.+ | .
| | |
/------------------+-----Data Flow---------------------------\
\------------------+-----------------------------------------/
| | |
This document describes a mechanism for performing authorization of a .-.-.-.-. SIP signaling
QoS reservation at a third party entity. Therefore, it is necessary - - - - - Diameter QoS Application messages
that the QoS signaling application to carry sufficient information
that should be forwarded to the backend AAA server. This
functionality is particularly useful in roaming environments where
the authorization decision is most likely provided at an entity where
the user can be authorized, such as in the home realm.
QoS signaling application MAY re-use the authenticated identities Figure 24: QoS Authorization Example - Push Mode
used for the establishment of the secured transport channel for the
signaling messages, e.g., TLS or IPsec between the end host and the
policy aware QoS NE. In addition, a collocation of the QoS NE with,
for example, the Diameter NASREQ application (see [RFC4005]) may
allow the QoS authorization to be based on the authenticated identity
used during the network access authentication protocol run. If a co-
located deployment is not desired then special security protection is
required to ensure that arbitrary nodes cannot reuse a previous
authentication exchange to perform an authorization decision.
Additionally, QoS authorization might be based on the usage of The communication starts with SIP signaling between the two end
authorization tokens that are generated by the Authorizing Entity and points and the SIP server for negotiation and authorization of the
provided to the end host via application layer signaling. requested service and its parameters (see Figure 24). As a part of
the process, the SIP server verifies whether the user at Host A is
authorized to use the requested service (and potentially the ability
to be charged for the service usage). The DQA server is triggered to
authorize the QoS request based on session parameters (i.e. SDP
offer), initiate a Diameter QoS authorization session and install
authorized QoS state to the Network Element via QIR message.
The impact of the existence of different authorization models is The DQA server may obtain the info of peer DQA client from pre-
(with respect to this Diameter QoS application) the ability to carry configured information or query the DNS based on Host A's identity or
different authentication and authorization information. IP address (In this case a DQA server is co-located with a SIP server
and a DQA client is co-located with a Network element). The identity
of Network Element is put into the Destination-Host AVP, the
description of the QoS resources is included into QoS-Resources AVP,
as well as duration of the authorization session (Authorization-
Lifetime AVP) and duration of the time (CC-Time) for which the end-
user should be charged with the rate announced in the QIR message.
The NE interacts with the traffic control function and reserves the
authorized QoS resources accordingly.
11. Acknowledgements With successful QoS authorization, the SDP offer in SIP Invite is
forwared to Host B. Host B sends back a 18x (ringing) message towards
Host A and processes the SDP. Once Host B accepts the call, it sends
back a 200 OK, in which it includes description of the accepted
session parameters (i.e. SDP answer).
The DQA server may verifies the accepted QoS against the pre-
authorized QoS resources, and sends a Diameter RAR message to the DQA
client in the network element for activating the installed policies
and commit the resource allocation. With successful QoS enforcement,
the 200 OK is forwarded towards Host A.
Note that the examples above show a sender-initiated reservation from
the End-Host towards the corresponding node and a receiver-initiated
reservation from the correspondent node towards the End-Host.
8. IANA Considerations
TBD
9. Security Considerations
TBD
10. Acknowledgements
The authors would like to thank John Loughney and Allison Mankin for The authors would like to thank John Loughney and Allison Mankin for
their input to this document. In September 2005 Robert Hancock, their input to this document. In September 2005 Robert Hancock,
Jukka Manner, Cornelia Kappler, Xiaoming Fu, Georgios Karagiannis and Jukka Manner, Cornelia Kappler, Xiaoming Fu, Georgios Karagiannis and
Elwyn Davies provided a detailed review. Robert also provided us Elwyn Davies provided a detailed review. Robert also provided us
with good feedback earlier in 2005. Jerry Ash provided us review with good feedback earlier in 2005. Jerry Ash provided us review
comments late 2005/early 2006. Rajith R provided some inputs to the comments late 2005/early 2006. Rajith R provided some inputs to the
document early 2007 document early 2007
[Editor's Note: Acknowledgements need to be updated.] [Editor's Note: Acknowledgements need to be updated.]
12. Contributors 11. Contributors
The authors would like to thank Tseno Tsenov (tseno.tsenov@gmail.com) The authors would like to thank Tseno Tsenov (tseno.tsenov@gmail.com)
and Frank Alfano (falfano@lucent.com) for starting the Diameter and Frank Alfano (falfano@lucent.com) for starting the Diameter
Quality of Service work within the IETF, for your significant draft Quality of Service work within the IETF, for your significant draft
contributions and for being the driving force for the first few draft contributions and for being the driving force for the first few draft
versions. versions.
[Editor's Note: A bit of history needs to be included here.] [Editor's Note: A bit of history needs to be included here.]
13. Open Issues 12. Open Issues
Open issues related to this draft are listed at the issue tracker Open issues related to this draft are listed at the issue tracker
available at: http://www.tschofenig.com:8080/diameter-qos/ available at: http://www.tschofenig.com:8080/diameter-qos/
14. References 13. References
14.1. Normative References 13.1. Normative References
[I-D.ietf-dime-qos-attributes] [I-D.ietf-dime-qos-attributes]
Korhonen, J., "Quality of Service Attributes for Diameter Korhonen, J., Tschofenig, H., Arumaithurai, M., and M.
and RADIUS", draft-ietf-dime-qos-attributes-00 (work in Jones, "Quality of Service Attributes for Diameter",
progress), July 2007. draft-ietf-dime-qos-attributes-03 (work in progress),
November 2007.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax [RFC2234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997. Specifications: ABNF", RFC 2234, November 1997.
[RFC3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and J. [RFC3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and J.
Arkko, "Diameter Base Protocol", RFC 3588, September 2003. Arkko, "Diameter Base Protocol", RFC 3588, September 2003.
[RFC4005] Calhoun, P., Zorn, G., Spence, D., and D. Mitton, [RFC4005] Calhoun, P., Zorn, G., Spence, D., and D. Mitton,
"Diameter Network Access Server Application", RFC 4005, "Diameter Network Access Server Application", RFC 4005,
August 2005. August 2005.
[RFC4006] Hakala, H., Mattila, L., Koskinen, J-P., Stura, M., and J. [RFC4006] Hakala, H., Mattila, L., Koskinen, J-P., Stura, M., and J.
Loughney, "Diameter Credit-Control Application", RFC 4006, Loughney, "Diameter Credit-Control Application", RFC 4006,
August 2005. August 2005.
14.2. Informative References 13.2. Informative References
[I-D.ietf-nsis-ntlp] [I-D.ietf-nsis-ntlp]
Schulzrinne, H. and R. Hancock, "GIST: General Internet Schulzrinne, H. and R. Hancock, "GIST: General Internet
Signalling Transport", draft-ietf-nsis-ntlp-13 (work in Signalling Transport", draft-ietf-nsis-ntlp-14 (work in
progress), April 2007. progress), July 2007.
[I-D.ietf-nsis-qos-nslp] [I-D.ietf-nsis-qos-nslp]
Manner, J., "NSLP for Quality-of-Service Signaling", Manner, J., "NSLP for Quality-of-Service Signaling",
draft-ietf-nsis-qos-nslp-14 (work in progress), June 2007. draft-ietf-nsis-qos-nslp-15 (work in progress), July 2007.
[RFC2210] Wroclawski, J., "The Use of RSVP with IETF Integrated [RFC2210] Wroclawski, J., "The Use of RSVP with IETF Integrated
Services", RFC 2210, September 1997. Services", RFC 2210, September 1997.
[RFC2486] Aboba, B. and M. Beadles, "The Network Access Identifier", [RFC2486] Aboba, B. and M. Beadles, "The Network Access Identifier",
RFC 2486, January 1999. RFC 2486, January 1999.
[RFC2749] Herzog, S., Boyle, J., Cohen, R., Durham, D., Rajan, R., [RFC2749] Herzog, S., Boyle, J., Cohen, R., Durham, D., Rajan, R.,
and A. Sastry, "COPS usage for RSVP", RFC 2749, and A. Sastry, "COPS usage for RSVP", RFC 2749,
January 2000. January 2000.
skipping to change at page 51, line 8 skipping to change at page 44, line 8
[RFC4027] Josefsson, S., "Domain Name System Media Types", RFC 4027, [RFC4027] Josefsson, S., "Domain Name System Media Types", RFC 4027,
April 2005. April 2005.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", RFC 4566, July 2006. Description Protocol", RFC 4566, July 2006.
Authors' Addresses Authors' Addresses
Glen Zorn (editor) Glen Zorn (editor)
Cisco Systems
2901 Third Avenue, Suite 600
SEA1/5/
Seattle, WA 98121
USA
Phone: +1 (425) 344 8113 Phone:
Email: gwz@cisco.com Email: glenzorn@comcast.net
Peter J. McCann Peter J. McCann
Motorola Labs Motorola Labs
1301 E. Algonquin Rd 1301 E. Algonquin Rd
Schaumburg, IL 60196 Schaumburg, IL 60196
USA USA
Phone: +1 847 576 3440 Phone: +1 847 576 3440
Email: pete.mccann@motorola.com Email: pete.mccann@motorola.com
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