Harri Hakala,
Leena Mattila
INTERNET-DRAFT Ericsson,
Draft:<draft-hakala-diameter-credit-control-03.txt> Juha-Pekka
Expires: December 2002 Koskinen
Nokia
June 2002
Diameter Credit Control Application
Status of this memo
This document is an Internet-Draft and is subject to all provisions
of Section 10 of RFC2026 except that the right to produce derivative
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This document is an individual submission to the IETF. Comments
should be directed to the authors.
Abstract
This document specifies a Diameter application that is used for real-
time cost and credit control between a service element and a credit
control server in service environment.
Diameter accounting messages with additional AVPs are used to
transfer service and credit control information between the service
element and the Credit Control Server.
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TABLE OF CONTENTS
1 Introduction
1.1 Requirements language
1.2 Terminology
1.3 Advertising application support
2 Architecture Model
3 Service Credit Control
3.1 Session Based Credit Control
3.1.1 First Interrogation
3.1.2 Interim Interrogation
3.1.3 Final Interrogation
3.1.4 Failure Procedures
3.2 One Time Event
3.2.1 Service Price Enquiry
3.2.2 Balance Check
3.2.3 Direct Debiting
3.2.4 Refund
3.2.5 Failure Procedures
3.3 Credit Control Session State Machine
4 Accounting AVPs
4.1 Abnormal-Termination-Reason AVP
4.2 Accounting-Correlation-Id AVP
4.3 Check-Balance-Result AVP
4.4 Cost AVP
4.5 Cost-Information AVP
4.6 Credit-Control-Failure-Handling AVP
4.7 Currency-Code AVP
4.8 Direct-Debiting-Failure-Handling AVP
4.9 Final-Unit-Indication AVP
4.10 Granted-Service-Unit AVP
4.11 Requested-Action AVP
4.12 Requested-Service-Unit AVP
4.13 Re-Transmission AVP
4.14 Service-Parameter-Info AVP
4.15 Service-Parameter-type AVP
4.16 Service-Parameter-Value AVP
4.17 Subscription-Id AVP
4.18 Subscription-Id-Data AVP
4.19 Subscription-Id-Type AVP
4.20 Unit-Type AVP
4.21 Unit-Value AVP
4.22 Used-Service-Unit AVP
5 Result-Code AVP Values
5.1 Transient Failures
5.2 Permanent Failures
6 AVP Occurrence Table
6.1 Accounting AVP Table
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7 IANA Considerations
7.1 Command Codes
7.2 AVP Codes
7.3 Result-Code AVP Values
7.4 Abnormal-Termination-Reason AVP
7.5 Check-Balance-Result AVP
7.6 Credit-Control-Realtime-Required AVP
7.7 Direct-Debiting-Failure-Handling AVP
7.8 Requested-Service-Unit AVP
7.9 Subscription-Id-Type AVP
7.10 Unit-Type AVP
7.11 Application Identifier
8 Credit Control Application related configurable parameter
9 Security Considerations
10 References
9.1 Normative
9.2 Non-Normative
11 Acknowledgements
12 Authors addresses
13 Full Copyright Statement
14 Expiration Date
1 Introduction
This Diameter application, combined with the Diameter base protocol
[DIAMBASE], describes the accounting protocol that can be used for
real time cost and credit control in the service environment.
The next generation wireless networks specify (e.g. 3G Charging and
Billing requirements [3GPPCHARG]) more critical requirements for the
accounting applications. The accounting application must be able to
rate accounting information in real-time. For example, for the
service environment it is vital to be able to rate service event
information instantly.
There also exists a demand for the end user credit control. The
accounting application must be able to check the end user's account
for coverage for the requested service event charge prior to
execution of that service event. All the chargeable events related to
a specific account must be prevented from the end user when the
credit of that account is exhausted or expired.
Also a mechanism should be provided to indicate to the end user of
the charges to be levied for a chargeable event.
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There are as well services such as gaming or advertising that in some
situations rather refund than deduct the end userÆs account.
To fulfill all these needs a new type of accounting application is
needed, the credit control application. This application is used for
real-time delivery of service event information in the service
environment from the service element to the Credit control server to
minimize the financial risk. This protocol is not only restricted to
be used in the service environment (it can for example also be used
for access control), but the focus is service control in service
environment.
1.1. Requirements language
In this document, the key words "MAY", "MUST, "MUST NOT", "optional",
"recommended", "SHOULD", and "SHOULD NOT", are to be interpreted as
described in [KEYWORDS].
1.2 Terminology
AAA
Authentication, Authorization and Accounting
Accounting
The act of collection of information on resource usage for the
purposes of trend analysis, auditing, billing or cost allocation.
Accounting Server
The accounting server receives accounting data from the service
elements and other devices and translates it into session records.
It acts as an interface to back-end rating, billing, and operations
support systems.
Billing
The act of preparing an invoice.
Charging
In the telecom world charging is synonym to accounting. A function
whereby information related to a chargeable event is transferred in
order to make it possible to determine usage for which the charged
party may be billed.
Credit Control
Credit control is a mechanism, which directly interacts in real-
time with an account and controls or monitors the charges, related
to the service usage. Credit control is a process of checking if
credit is available, credit-reservation, reduction of credit from
the end user account when service is completed and refunding of
reserved credit not used.
Credit Control Server
It is located in the home environment and is accessed by service
elements in real-time for purpose of price determination and credit
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control before the service event is delivered to the end-user. It
also interacts with business support systems.
Diameter Credit Control Client
A Diameter credit control client is an entity that interacts with a
credit control server.
Diameter Credit Control Server
A Diameter credit control server is an entity that handles credit
control request.
Rating
The act of determining the cost of the service event.
Service
A type of task that is performed by a service element for a service
consumer.
Service Consumer
Client of a service element. End user of a network service.
Service Element
A network element that provides a service to service consumers.
A service element itself can include the application service
providers or application service providers can be located in an
other domain.
Service Event
Any event which creates value for the end-user.
1.3 Advertising application support
Diameter nodes conforming to this specification MAY advertise support
by including the value of TBD (X) in the Acct-Application-Id AVP of
the Capabilities-Exchange-Request and Capabilities-Exchange-Answer
command [DIAMBASE].
2 Architecture Model
A service element provides services to service consumers. When
accounting is used a service element collects service event
information and reports it while and/or after services are provided
to an accounting server by using an accounting protocol.
Alternatively the accounting server may query the service element for
service event information.
The accounting protocol can for example be RADIUS accounting protocol
or the Diameter base protocol with a Diameter application.
If real-time credit control is required, the service element contacts
the Credit control server with service event information included
before the service is provided. The credit control server, depending
on the service event information, MAY perform the rating of the
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service event, pricing of the service event, credit check and credit-
reservation from the account. The service element monitors the
service execution according to the instructions returned by the
credit control server. After the service completion the credit
control server deducts the money from the account.
If direct debiting/refunding is requested, the credit control server
deducts/increases the end userÆs account, respectively. The service
element can also enquire the price of the service or the account
balance status from the credit control server.
The credit control protocol is the Diameter base protocol with the
Diameter credit control application.
accounting
+------------+ +-----------+ protocol +--------------+
| Service |<----->| Service |<------------>| Accounting |
| Consumer | +-->| Element |<-----+ | Server |
+------------+ | +-----------+ | +--------------+
| |
+------------+ | |
| Service |<--+ | +--------------+
| Consumer | +------>|Credit Control|
+------------+ credit control | Server |
protocol +--------------+
The credit control server and accounting server in this architecture
model are logical entities. The real configuration MAY combine them
into a single host.
3 Service Control
When an end user requests a service the request is forwarded to a
service element in the home domain, that is the same administrative
domain, in which the end user's credit control server is located. In
some cases it might be possible that the service element in the
visited domain can offer service event to the end user, but in that
case a commercial agreement must exist between the service element in
the visited domain and in the home domain.
The service element SHOULD authenticate and authorize the end user
before any request is sent to the Credit Control Server. The way how
the authentication and/or authorization are performed in the service
element and the authentication and/or authorization messages that are
used are not defined in this application. The methods defined in
other Diameter applications or other legacy authentication and
authorization methods can be used.
The Diameter protocol's Session-Id AVP, which is globally and
eternally unique [DIAMBASE], is used during the authorization phase
to identify a particular session. Each credit control session SHOULD
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use a different Session-Id from that sent in authorization messages
and it MUST NOT be changed during a life of credit control session.
The Diameter Credit Control Client in the service element MAY get
information from the authorization server regarding the way
accounting data shall be forwarded (accounting protocol or credit
control protocol) based on its knowledge of the end user. This means
that the accounting information is forwarded to the accounting server
as defined [DIAMBASE] or the credit control server SHOULD be
contacted before the service event is offered to the end user.
The authorization server MAY include the Accounting-Realtime-Required
AVP to determine what to do if the sending of accounting records to
the accounting server has been temporarily prevented as defined in
[DIAMBASE]. The Accounting-Realtime-Required AVP is not used by this
application. Instead of or in addition to the Accounting-Realtime-
Required AVP the authorization server MAY include the Credit-Control-
Failure-Handling AVP and Direct-Debiting-Failure-Handling AVP to
determine what to do if the sending of credit control messages to the
credit control server has been temporarily prevented. The usage of
Credit-Control-Failure-Handling AVP and the Direct-Debiting-Failure-
Handling AVP gives flexibility to have different failure handling for
credit control session and one time event direct debiting. The credit
control server MAY override the failure handling for credit control
session by including the Credit-Control-Failure-Handling AVP in the
Accounting-Answer.
The usage of separate AVPs makes it possible to have different
failure handling towards accounting servers and credit control
servers, in case both should be used parallel. It is recommended that
the client complements the credit control failure procedures with
backup accounting flow towards an accounting server. With different
combinations of above AVPs different safety levels can be built.
For example by choosing the Credit-Control-Failure-Handling AVP equal
to CONTINUE and Accounting-Realtime-Required AVP equal to
DELIVER_AND_GRANT the service can be granted to the end user even if
the connection to the credit control server is down but the
accounting server is able to collect the accounting information,
provided that there is information exchange taking place between the
accounting server and credit control server.
If authentication and authorization is done based on Diameter
application the authorization server MAY include the Acct-Interim-
Interval AVP to control the operation of the device in the service
element operating as a client as defined in [DIAMBASE]. If the Acct-
Interim-Interval AVP is included then the interim interval MAY be
present in the request message sent to the Credit Control Server.
The Diameter credit control server MAY override the interim interval.
It is up to the credit control server to determine, even
independently from the requested value, the allowed interim interval
to be used for consumption of the granted service units. The credit
control server MAY return the interim interval in the Answer message
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to the credit control client. It can be included in the Answer
message even in case it is not present in the Request message.
Alternatively the accounting interim interval can be omitted from the
Answer message. However, since interim records are also produced at
the expiry of granted service units and/or for mid-session service
events the omission of Acct-Interim-Interval does not mean that
interim records are not produced.
During authorization, the authorization server MAY return the
Accounting-Multi-Session-Id, which the Diameter credit control client
MAY include in all subsequent accounting messages. The Accounting-
Multi-Session-Id AVP MAY include the value of the original Session-
Id. It's contents are implementation specific, but MUST be globally
unique across other Accounting-Multi-Session-Id, and MUST NOT be
changed during the life of a credit control session.
There are certain applications that require multiple accounting sub-
sessions. Such applications would send messages with a constant
Session-Id AVP, but a different Accounting Sub-Session-Id AVP.
If several credit sub-sessions will be used, all sub-sessions MUST be
closed separately before the closing the main session. The absence of
this AVP implies no sub-sessions are in use.
If the credit control client wants to perform credit-reservation
before granting service to the end user it MUST use several
interrogations towards the credit control server. In this case the
credit control server MUST maintain the accounting session state.
A one time event MAY be used when there is no need to maintain any
state in the Diameter Credit Control Server, for example enquiring
the price of the service.
3.1 Session Based Credit Control
For a session based credit control several interrogations are needed:
the first, intermediate (optional) and the final interrogation.
3.1.1 First Interrogation
The first interrogation MUST be sent before the Diameter credit
control client in a service element allows any service event to the
end user. The Accounting-Record-Type is set to the value START_RECORD
in the first request message. The Subscription-Id-Data AVP SHOULD be
included to identify the end-user in the Credit Control Server.
If the Diameter credit control client knows the cost of the service
event the monetary amount to be charged is included in the Requested-
Service-Unit AVP. If the Diameter credit control client does not know
the cost of the service event, the Requested-Service-Unit AVP MAY
contain the number of requested service events and the Service-
Parameter-Info AVP SHOULD contain the service event information to be
rated by the credit control server. The Service-Parameter-Info AVP
always refers to the requested service units.
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The Event-Timestamp AVP contains the time when the service event is
requested in the service element.
The credit control server SHOULD rate the service event and make a
credit-reservation from the end user's account that covers the cost
of the service event. If the type of the Requested-Service-Unit AVP
is money, no rating is needed but the corresponding monetary amount
is reserved from end user's account.
The credit control server returns the Granted-Service-Unit AVP in the
Answer message to the Diameter credit control client. The Granted-
Service-Unit AVP contains the amount of service units that the
Diameter credit control client can provide to the end user until a
new Accounting-Request MUST be sent to the credit control server. If
several unit types are sent in the Answer message the credit control
client MUST handle each unit type separately. When the granted
service units for one unit type have been spent a new Accounting-
Request MUST be sent to the credit control server even though there
would be service units left for other units types. The type of the
Granted-Service-Unit AVP can be time, volume, event or money
depending on the type of service event. It is not possible to change
the unit type(s) within the session.
If the credit control server determines that no further control is
needed for the service it MAY include the result code indicating that
the credit control is not applicable (e.g. service is free of charge)
and terminate the credit control session.
The Accounting-Answer message MAY also include the Final-Unit-
Indication AVP to indicate that the Answer message contains the final
units for the service session. After the end user has used these
units, the Diameter credit control client is responsible for
terminating the service session and the credit control session by
sending the final interrogation to the credit control server.
3.1.2 Intermediate Interrogation
When all the granted service units for one unit type are spent by the
end user or the interim interval is expired the Diameter credit
control client MUST send a new Accounting-Request to the Credit
Control Server. In case the Acct-Interim-Interval is used it is
always up to the Diameter credit control client to send a new request
well in advance before the expiration of the previous request in
order to avoiding interruption in the service element. Even if the
granted service units reserved by the credit control server have not
been spent upon expiration of the accounting interim interval, the
Diameter credit control client MUST send a new Accounting-Request to
the Credit Control Server.
There can be also mid-session service events, which might affect the
rating of the current service events. In this case a spontaneous
updating (a new Accounting-Request) SHOULD be sent including
information related to the service event even if all the granted
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service units have not been spent or the accounting interim interval
has not expired.
When the used units are reported to the credit control server the
credit control client will not have any units in its possession
before new granted units are received from the Credit Control Server.
When the new granted units are received from the Credit control
Server these units apply from the point where the measurement of the
reported used units stopped.
The Accounting-Record-Type AVP is set to the value INTERIM_RECORD in
the intermediate request message. The Subscription-Id-Data AVP SHOULD
also be included in the intermediate message to identify the end user
the in Credit Control Server.
The Requested-Service-Unit AVP contains the new amount of requested
service units, the Used-Service-Unit AVP contains the amount of used
service units since the previous Answer message. The same unit types
that are used in the previous message MUST be used. If several unit
types were included in the previous Answer message the used service
units for each unit type MUST be reported.
The Event-Timestamp AVP contains the time of the event that triggered
the sending of the new Accounting-Request.
The credit control server MUST refund the reserved credit amount not
used to the end user's account and deduct the used monetary amount
from the end user's account.
The rating of the new service event, the credit-reservation from the
end user's account and the possible final unit indication SHOULD be
handled in a similar way as described in the first interrogation.
The Accounting-Answer message with the Accounting-Record-Type AVP is
set to the value INTERIM_RECORD MAY include the Cost-Information AVP
containing the accumulated cost for the session without taking any
credit-reservation into account.
There MAY be several intermediate interrogations within a session.
3.1.3 Final Interrogation
When the end user terminates the service session or when all the
granted units are used after a Final-Unit-Indication AVP has been
received from the Credit Control Server, the Diameter credit control
client MUST send a final Accounting-Request message to the credit
control server. The Accounting-Record-Type AVP is set to the value
STOP_RECORD.
The Event-Timestamp AVP MAY contain the time of the session was
terminated.
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The Used-Service-Unit AVP contains the amount of used service units
since the previous answer message. If several unit types were
included in the previous answer message the used service units for
each unit type MUST be reported.
After final interrogation the credit control server MUST refund the
reserved credit amount not used to the end user's account and deduct
the used monetary amount from the end user's account.
The Accounting-Answer message with the Accounting-Record-Type set to
the value STOP_RECORD SHOULD include the Cost-Information AVP
containing the total cost for the session in question.
3.1.4 Failure Procedures
Since the credit control application is based on real-time bi-
directional communication between the credit control client and the
credit control server alternative destinations and buffering of
messages are not sufficient in the event of transport failures. Since
the credit control server has to maintain a session state the credit
control message stream MUST not be moved to a backup credit control
server during an ongoing credit control session.
If a transport failure occurs during an ongoing credit control
session the credit control client will terminate or continue the
service depending on the value set in the Credit-Control-Failure-
Handling AVP. The Credit-Control-Failure-Handling AVP MAY be sent
from the authorization server and in the Accounting-Answer from the
credit control server. For new credit control sessions failover to
alternative credit control server SHOULD be performed, if possible.
The timer Tx (as defined in section 8) is used in the credit control
client to supervise the communication with the Credit Control Server.
If the credit control server detects a failure during an ongoing
credit control session it will terminate the Credit Control session
and return the reserved units back to the end userÆs account.
The supervision session timer Ts as defined in [DIAMBASE] is used in
the Credit Control Server.
3.2 One Time Event
The one time event is used when there is no need to maintain
accounting session state in the credit control server.
The one time event can be used when the service element wants to know
the cost of the service event without any credit-reservation or to
check the account balance without any credit-reservation. It can be
used also for refunding service units on the user's account or direct
debiting without any credit-reservation.
3.2.1 Service Price Enquiry
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Sometimes the service element needs to know the price of the service
event. There might exist services offered by application service
providers, whose prices are not known in the service element. End
user might also want to get an estimation of the price of a service
event before requesting it.
A Diameter credit control client requesting the cost information MUST
set the Accounting-Record-Type AVP equal to EVENT_RECORD, include the
Requested-Action AVP set to PRICE_ENQUIRY and set the requested
service event information into the Service-Parameter-Info AVP in the
Accounting-Request message.
The credit control server calculates the cost of the requested
service event, but it does not perform any account balance check or
credit-reservation from the account.
The price of the requested service event is returned to the credit
control client in the Cost-Information AVP in the Accounting-Answer
message.
3.2.2 Balance Check
Sometimes Diameter credit control client needs only to verify that
the end userÆs account balance covers the cost for a certain service
without reserving any units from the account at the time of the
enquiry. This method does not guarantee that there would be credit
left when the Diameter credit control client requests the debiting of
the account with a separate request.
A Diameter credit control client requesting the balance check MUST
set the Accounting-Record-Type AVP equal to EVENT_RECORD, include
Requested-Action AVP set to CHECK_BALANCE and include the
Subscription-Id-Data to identify the End-User in the Credit Control
Server.
The credit control server makes the balance check, but it does not do
any credit-reservation from the account.
The result of balance check (Credit/No Credit) is returned to the
credit control client in the Check-Balance-Result AVP in the
Accounting-Answer message.
3.2.3 Direct Debiting
There are certain one time events for which service execution is
always successful in the service environment. Sometimes the delay
between the service invocation and the actual service delivery to the
end user can be so long that the use of the session based credit
control would lead to unreasonable long credit control sessions.
In these cases the Diameter credit control client can use the one
time event scenario for direct debiting. The Diameter credit control
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client MUST be sure that the requested service event execution will
be successful, when this scenario is used.
The Accounting-Record-Type is set to the value EVENT_RECORD and the
Requested-Action AVP set to DIRECT_DEBITING in the Accounting-Request
message. The Subscription-Id-Data AVP SHOULD be included to identify
the End-User in the Credit Control Server. The Event-Timestamp AVP
contains the time when the service event is requested in the service
element.
The Diameter credit control client MAY include the monetary amount to
be charged in the Request-Service-Unit AVP, if it knows the cost of
the service event. If the Diameter credit control client does not
know the cost of the service event, then the Service-Parameter-Info
AVP SHOULD contain the service event information to be rated by the
Credit Control Server. The Service-Parameter-Info AVP always refers
to the requested service unit.
The credit control server SHOULD rate the service event and deduct
the corresponding monetary amount from end user's account. If the
type of the Requested-Service-Unit AVP is money, no rating is needed
but the corresponding monetary amount is deducted from the End User's
account.
The credit control server returns the Granted-Service-Unit AVP in the
Answer message to the Diameter credit control client. The Granted-
Service-Unit AVP contains the amount of service units that the
Diameter credit control client can provide to the end user. The type
of the Granted-Service-Unit can be time, volume, event or money
depending on the type of service event.
If the credit control server determines that no credit control is
needed for the service it MAY include the result code indicating that
the credit control is not applicable (e.g. service is free of
charge).
The Accounting-Answer message SHOULD also include the Cost-
Information AVP containing the total cost of the requested service.
3.2.4 Refund
There MAY be a need to refund service units on the end userÆs
account, for example gaming services.
The credit control client MUST set Accounting-Record-Type AVP to the
value EVENT_RECORD and the Requested-Action AVP to REFUND in the
Accounting-Request message. The Subscription-Id-Data AVP SHOULD be
included to identify the End-User in the Credit Control Server.
The Diameter credit control client MAY include the monetary amount to
be refunded in the Request-Service-Unit AVP, if it knows the cost of
the service event. If the Diameter credit control client does not
know the cost of the service event, then the Service-Parameter-Info
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AVP SHOULD contain the service event information to be rated by the
Credit Control Server. The Service-Parameter-Info AVP always refers
to the requested service unit.
The Accounting-Answer message MAY also include the Cost-Information
AVP containing the monetary amount of refunded unit.
3.2.5 Failure Procedure
When the credit control client detects a transport failure with the
credit control server its behavior depends on the requested action.
In case of Service Price Enquiry or Balance Check the request
messages MAY be forwarded to an alternative Credit Control server, if
possible.
If the requested action is DIRECT_DEBITING and the Direct-Debiting-
Failure-Handling AVP is set to TERMINATE_OR_BUFFER the credit control
client SHOULD terminate the service if it can determine from the
failed answer that units have not been debited. Otherwise the credit
control client SHOULD grant the service to the end user and apply the
failover and failback procedures defined in [DIAMBASE] to re-send the
message. If the Direct-Debiting-Failure-Handling is set to CONTINUE
the service SHOULD be granted even if credit control messages canÆt
be delivered. The Client MAY re-send the request to an alternative
server, if possible. The credit control client shall mark the re-
transmitted request message as possible duplicate with the Re-
Transmission AVP.
The Accounting-Request with requested action REFUND should always be
buffered and re-sent in case of temporary failure. The credit control
client shall mark the re-transmitted request message as possible
duplicate with the Re-Transmission AVP.
The implementation MAY choose to limit the number of re-transmission
attempts.
The credit control server is therefore responsible for the real time
duplicate detection. Implementation issues for duplicate detection
are discussed in [DIAMBASE] Appendix C. The implementation of credit
control server MAY use the Re-Transmission AVP for optimizing the
duplicate detection procedure. The massive all-against-all record
checking with a certain time window SHOULD be avoided.
3.3 Credit Control Session State Machine
The following state machines MUST be supported for credit control
applications.
The first two state machines are to be observed by credit control
clients. The first one describes the session based credit control and
the second one event based credit control. The third state machine
describes the credit control session control from a credit control
server perspective.
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Any event not listed in the state machines MUST be considered as an
error condition, and a corresponding answer, if applicable, MUST be
returned to the originator of the message.
In the state table, the event 'Failure to send' means that the
Diameter credit control client is unable to communicate with the
desired destination. This could be due to the peer being down, or due
to the peer sending back a transient failure or temporary protocol
error notification DIAMETER_TOO_BUSY, or DIAMETER_LOOP_DETECTED in
the Result-Code AVP of the Accounting Answer command.
The event 'Failed answer' means that the Diameter client received a
non-transient failure notification in the Accounting Answer command.
The event 'Not successfully processed' means that the Credit control
server could not process the message, e.g. due to unknown end user,
account being empty or due to errors defined in [DIAMBASE].
The states PendingS, PendingI, PendingL PendingE and PendingB stand
for pending states to wait for an answer to an accounting request
related to a Start, Interim, Stop, Event or Buffered record
respectively.
CLIENT, SESSION BASED
State Event Action New State
---------------------------------------------------------------
Idle Client or device requests Send PendingS
access accounting
start req.,
start Tx.
PendingS Successful accounting Stop Tx Open
start answer received
PendingS Failure to send Grant Idle
and credit control fault service to
handling equal to CONTINUE end user.
PendingS Failure to send Disconnect Idle
and credit control fault user/dev
handling equal to TERMINATE
PendingS Tx expired and credit Disconnect Idle
Control fault handling user/dev
Equal to TERMINATE
PendingS Tx expired and credit control Grant Idle
fault handling equal to service to
CONTINUE end user
PendingS Accounting start answer Disconnect Idle
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received with result code user/dev
SERVICE_ DENIED or
USER_NOT_FOUND
PendingS Accounting start answer Grant Idle
received with result code service
equal to credit control N/A to end user
PendingS Failed accounting start answer Grant Idle
received and credit control Service to
fault handling end user
equal to CONTINUE
PendingS Failed accounting start answer Disconnect Idle
received and credit control user/dev
failure handling equal to
TERMINATE
PendingS User service terminated Queue PendingS
termination
event
PendingS Change in rating condition Queue PendingS
changed
rating
condition
event
Open Granted unit elapses Send PendingI
and no final unit accounting
indication received interim req.,
start Tx.
Open Granted unit elapses Disconnect PendingL
and final unit indication send
received accounting
stop req.,
start Tx.
Open Change in rating condition Send PendingI
in queue accounting
interim req.,
Start Tx.
Open Service terminated in queue Send PendingL
accounting
stop req.,
start Tx
Open Change in rating condition Send PendingI
or interim interval elapses accounting
interim req.,
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Start Tx.
Open User service terminated Send PendingL
accounting
stop req.,
start Tx
PendingI Successful accounting interim Stop Tx Open
answer received
PendingI Failure to send Grant Idle
and credit control fault service to
handling equal to CONTINUE end user.
PendingI Failure to send Disconnect Idle
and credit control fault user/dev
handling equal to TERMINATE
PendingI Tx expired and credit control Disconnect Idle
fault handling equal to user/dev
TERMINATE
PendingI Tx expired and credit control Grant Idle
fault handling equal to service to
CONTINUE end user.
PendingI Accounting interim answer Disconnect Idle
received with result code user/dev
SERVICE_DENIED
PendingI Accounting interim answer Grant Idle
received with result code service
equal to credit control N/A to end user
PendingI Failed accounting interim Grant Idle
answer received and credit service to
control fault handling equal end user.
to CONTINUE
PendingI Failed accounting interim Disconnect Idle
answer received and credit user/dev
control fault handling
equal to TERMINATE
PendingI User service terminated Queue PendingI
termination
event
PendingI Change in rating Queue PendingI
condition changed
rating
condition
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event
PendingL accounting stop Idle
answer received
PendingL Tx expired Idle
PendingL Failure to send Idle
PendingL Change in rating condition PendingL
CLIENT, EVENT BASED
State Event Action New State
----------------------------------------------------------------
Idle Client or device requests Send PendingE
a one-time service accounting
event req.,
Start Tx.
Idle Records in storage Send PendingB
stored
record
marked with
Re-Transmission,
Start Tx
PendingE Successful accounting Idle
event answer received
PendingE Failed accounting event Idle
answer received, requested
action GET_BALANCE or
PRICE_ENQUIRY
PendingE Tx expired and requested Idle
Action GET_BALANCE or
PRICE_ENQUIRY
PendingE Accounting event answer Disconnect Idle
received with result code user/dev
SERVICE_ DENIED or
USER_NOT_FOUND
PendingE Accounting event answer Grant Idle
received with result code service
credit control N/A, requested to end
action DIRECT_DEBITING user
PendingE Failed accounting event Grant Idle
answer received, requested service
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action DIRECT_DEBITING and to end
fault handling equal to user
CONTINUE
PendingE Failed accounting event Disconnect Idle
answer received, requested user/dev
action DIRECT_DEBITING and
fault handling equal to
TERMINATE_OR_BUFFER
PendingE Tx expired and Grant Idle
requested action service
DIRECT_DEBITING, fault to end
handling equal to user
CONTINUE
PendingE Tx expired and Grant Idle
requested action service
DIRECT_DEBITING, fault to end
handling equal to user and
TERMINATE_OR_BUFFER store event
record
PendingE Failed accounting event Indicate Idle
answer received, requested service
action REFUND error and
delete record
PendingE Tx expired and Store Idle
requested action event
REFUND record
PendingB Successful accounting answer Delete Idle
received record
PendingB Failed accounting answer Delete Idle
received record
PendingB Failure to send Idle
PendingB Tx expired Idle
SERVER, SESSION AND EVENT BASED
State Event Action New State
----------------------------------------------------------------
Idle Accounting start request Send Open
received and successfully accounting
processed. start
answer,
reserve units,
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start Ts
Idle Accounting start request Send Idle
received, but not accounting
successfully processed. start
Answer with
Result-Code
!= SUCCESS
Idle Accounting event request Send Idle
received and successfully accounting
processed. event
answer,
debit units
Idle Accounting event request Send Idle
received, but not accounting
successfully processed. event
Answer with
Result-Code
!= SUCCESS
Open Accounting Interim record Send Open
received and successfully accounting
processed answer,
debit used
units and
reserve
new units,
Restart Ts
Open Accounting interim request Send Idle
received, but not accounting
successfully processed. interim
Answer with
Result-Code
!= SUCCESS,
debit used
units
Open Accounting stop request Send Idle
received, and successfully accounting
processed stop answer,
Stop Ts,
debit used
units
Open Accounting stop request Send Idle
received, but not accounting
successfully processed. stop
Answer with
Result-Code
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!= SUCCESS,
debit used
units
Open Session supervision timer Ts Stop Ts, Idle
expired release
reserved
units
4 Accounting AVPs
This section defines the accounting AVPs that are specific to
Diameter Credit Control Application and MAY be included in the
Diameter accounting messages [DIAMBASE].
Accounting-Request command MAY include a following additional AVPS:
[ Subscription-Id ]
[ Requested-Action ]
*[ Requested-Service Unit ]
*[ Used-Service-Unit ]
*[ Service-Parameter-Info ]
[ Abnormal-Termination-Reason]
*[ Accounting-Correlation-Id ]
[ Credit-Control-Failure-Handling ]
[ Direct-Debiting-Failure-Handling ]
[ Re-Transmission ]
Accounting-Answer command MAY include a following additional AVPS:
[ Subscription-Id ]
*[ Granted-Service-Unit ]
[ Cost-Information]
[ Final-Unit-Indication ]
[ Check-Balance-Result ]
[ Credit-Control-Failure-Handling ]
The following table describes the Diameter AVPs defined in Credit
Control application, their AVP Code values, types, possible flag
values and whether the AVP MAY be encrypted.
+---------------------+
| AVP Flag rules |
|----+-----+----+-----|----+
AVP Section | | |SHLD| MUST|MAY |
Attribute Name Code Defined Data Type |MUST| MAY | NOT| NOT|Encr|
-----------------------------------------|----+-----+----+-----|----|
Abnormal- XXX 4.1 Enumarated | M | P | | V | Y |
Termination-Reason | | | | | |
Accounting- XXX 4.2 OctetString| M | P | | V | Y |
Correlation-Id | | | | | |
Check-Balance- XXX 4.3 Enumarated | M | P | | V | Y |
Result | | | | | |
Cost-Information XXX 4.5 Grouped | M | P | | V | Y |
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Credit-Control- XXX 4.6 Enumarated | M | P | | V | Y |
Failure-Handling | | | | | |
Direct-Debiting XXX 4.8 Enumarated | M | P | | V | Y |
Failure-Handling | | | | | |
Final-Unit- XXX 4.9 Unsigned32 | M | P | | V | Y |
Indicator | | | | | |
Granted-Service- XXX 4.10 Grouped | M | P | | V | Y |
Unit | | | | | |
Requested-Action XXX 4.11 Enumarated | M | P | | V | Y |
Requested-Service XXX 4.12 Grouped | M | P | | V | Y |
Unit | | | | | |
Re-Transmission XXX 4.13 Unsigned32 | M | P | | V | Y |
Service-Parameter XXX 4.14 Grouped | M | P | | V | Y |
Info | | | | | |
Subscription-Id XXX 4.17 Grouped | M | P | | V | Y |
Used-Service-Unit XXX 4.22 Grouped | M | P | | V | Y |
-----------------------------------------+----+-----+----+-----+----+
4.1 Abnormal-Termination-Reason AVP
The Abnormal-Termination-Reason AVP (AVP Code TBD) is of type
Enumerated and contains information about the reason for an abnormal
service termination in a service element.
The following reasons are defined:
SERVICE_ELEMENT_TERMINATION 0
An error occurred in the service element.
CONNECTION_TO_END-USER_BROKEN 1
The connection to the end-user is broken.
4.2 Accounting-Correlation-Id AVP
The Accounting-Correlation-Id AVP (AVP Code TBD) is type of
OctetString and contains information to correlate accounting data
generated for different components of the service, e.g. transport and
service level.
4.3 Check-Balance-Result AVP
The Check Balance Result AVP (AVP code TBD) is of type Enumerated and
contains the result of the balance check. This AVP is applicable only
when the Requested-Action AVP indicates CHECK_BALANCE in the
Accounting-Request command.
The following values are defined for the Check-Balance-Result AVP.
ENOUGH_CREDIT 0
There is enough credit in the account to cover the requested
service.
NO_CREDIT 1
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There isnÆt enough credit in the account to cover the
requested service.
4.4 Cost AVP
The Cost AVP (AVP Code TBD) is of type Float64 and contains the cost
estimate of the service in case of price enquiry or the accumulated
cost in the case of credit control session.
4.5 Cost-Information AVP
The Cost-Information AVP (AVP Code TBD) is of type Grouped and is
used to return the cost information of a service in the Accounting-
Answer command. The included Cost AVP contains the cost of the
service event and the Currency-Code specifies in which currency the
cost was given.
When the Requested-Action AVP with value PRICE_ENQUIRY is included in
the Accounting-Request command the Cost-Information AVP sent in the
succeeding Accounting-Answer command contains the cost estimation of
the requested service, without any reservation being made.
The Cost-Information AVP included in the Accounting-Answer command
with the Accounting-Record-Type set to INTERIM_RECORD contains the
accumulated cost for the session without taking any credit-
reservation into account.
The Cost-Information AVP included in the Accounting-Answer command
with the Accounting-Record-Type set to EVENT_RECORD or STOP_RECORD
contains the total cost for the requested service.
It has the following ABNF grammar:
<Cost-Information>::=< AVP Header: TBD >
{ Cost }
{ Currency-Code }
4.6 Credit-Control-Failure-Handling AVP
The Credit-Control-Failure-Handling AVP (AVP Code TBD) is of type
Enumerated. The credit control client uses information in this AVP to
decide what to do if the sending of credit control messages to the
credit control server has been for instance temporarily prevented due
to a network problem.
TERMINATE 0
When the Credit-Control-Failure-Handling AVP is set to TERMINATE
the service MUST only be granted as long as there is a
connection to the Credit Control Server. If the credit control
client does not receive any Accounting-Answer message within the
Tx timer (as defined in section 8) the transport connection is
regarded failed. The moving of already started credit control
session to alternative server is not allowed.
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This is the default behaviour if the AVP isnÆt included in the
reply from the authorization or credit control server.
CONTINUE 1
When the Credit-Control-Failure-Handling AVP is set to CONTINUE
the service SHOULD be granted even if credit control messages
canÆt be delivered.
4.7 Currency-Code AVP
The Currency-Code AVP (AVP Code TBD) is of type Unsigned32 and
contains a currency code that specifies in which currency the values
of AVPs containing monetary units were given. It is specified using
the numeric values defined in the ISO 4217 standard.
4.8 Direct-Debiting-Failure-Handling AVP
The Direct-Debiting-Failure-Handling AVP (AVP Code TBD) is of type
Enumerated. The credit control client uses information in this AVP to
decide what to do if the sending of credit control messages
(Requested-Action AVP set to Direct Debiting) to the credit control
server has been for instance temporarily prevented due to a network
problem.
TERMINATE_OR_BUFFER 0
When the Direct-Debiting-Failure-Handling AVP is set to
TERMINATE_OR_BUFFER the service MUST be granted as long as there
is a connection to the Credit Control Server. If the credit
control client does not receive any Accounting-Answer message
within the Tx timer (as defined in section 8) the transport
connection is regarded failed. The client SHOULD terminate the
service if it can determine from the failed answer that units
have not been debited. Otherwise the credit control client
SHOULD grant the service, buffer the request and try to re-send
the request. The re-transmitted request messages SHOULD be
marked with the Re-Transmission AVP.
This is the default behaviour if the AVP isnÆt included in the
reply from the authorization server.
CONTINUE 1
When the Direct-Debiting-Failure-Handling AVP is set to CONTINUE
the service SHOULD be granted even if credit control messages
canÆt be delivered.
4.9 Final-Unit-Indication AVP
The Final-Unit-Indication AVP (AVP Code TBD) is of type Unsigned32
and indicates that the Granted-Service-Unit AVP in the accounting
command contains the final units for the service. After these units
have expired, the Diameter credit control client in a service element
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is responsible for terminating the service and sending the
STOP_RECORD to the Credit Control Server.
If more than one unit types are received in Accounting-Answer, the
Unit type which first expired SHOULD be caused the termination.
If included in a command, the value of this AVP is always 1.
4.10 Granted-Service-Unit AVP
Granted-Service-Unit AVP (AVP Code TBD) is of type Grouped and
contains the amount of units that the Diameter credit control client
can provide to the end user until the service must be released or the
new Accounting-Request must be sent. The Unit-Value AVP contains the
granted Unit-Value and the Unit-Type AVP defines the type of the
unit. If the unit type is money, a Currency-Code AVP SHOULD be
included.
It has the following ABNF grammar:
<Granted-Service-Unit>::=< AVP Header: TBD >
{ Unit-Type }
{ Unit-Value }
[ Currency-Code ]
4.11 Requested-Action AVP
The Requested-Action AVP (AVP Code TBD) is type of Enumerated and
contains the requested action being sent by Accounting-Request
command where the Accounting-Record-Type is set to EVENT_RECORD.
The following values are defined for the Requested-Action AVP:
DIRECT DEBITING 0
Direct debiting indicates that the request is to decrease the
end userÆs account according to information specified in the
Requested-Service-Unit AVP and/or Service-Parameter-Info AVP.
The Granted-Service Unit AVP in the Accounting-Answer command
contains the debited units.
REFUND ACCOUNT 1
Refund account indicates that the request is to increase the end
userÆs account according to information specified in the
Requested-Service-Unit AVP and/or Service-Parameter-Info AVP.
The Granted-Service Unit AVP in the Accounting-Answer command
contains the refunded units.
CHECK_BALANCE 2
Check balance indicates that the request is a balance check
request. In this case the checking of the account balance is
done without any credit reservation from the account. The Check-
Balance-Result AVP in the Accounting-Answer command contains the
result of the Balance Check.
PRICE_ENQUIRY 3
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Price Enquiry indicates that the request is a price enquiry
request. In this case neither checking of the account balance
nor reservation from the account will be done, only the price of
the service will be returned in the Cost-Information AVP in the
Accounting-Answer Command.
4.12 Requested-Service-Unit AVP
The Requested-Service-Unit AVP (AVP Code TBD) is of type Grouped and
contains the amount of requested units specified by the Diameter
credit control client. The included Unit-Value AVP contains the
requested Unit-Value and the Unit-Type AVP defines the type of the
unit. If the unit type is money, a Currency-Code AVP SHOULD be
included.
It has the following ABNF grammar:
<Requested-Service-Unit>::=< AVP Header: TBD >
{ Unit-Type }
{ Unit-Value }
[ Currency-Code ]
4.13 Re-Transmission AVP
The Re-Transmission AVP (AVP code TBD) is type of Unsigned32 and it
indicates the possible duplicate request in case of transmission
failure. The implementation of credit control server MAY use this AVP
for optimizing the duplicate detection procedure.
If included in a command, the value of this AVP is always 1.
4.14 Service-Parameter-Info AVP
The Service-Parameter-Info AVP (AVP Code TBD) is of type Grouped and
contains a service specific information used for price calculation or
rating. The Service-Parameter-Type AVP defines the service parameter
type and the Service-Parameter-Value AVP contains the parameter
value. The actual contents of these AVPs are not within the scope of
this document and SHOULD be defined in additional service specific
documentation.
It has the following ABNF grammar:
<Service-Parameter-Info>::=< AVP Header: TBD >
{ Service-Parameter-Type }
{ Service-Parameter-Value}
4.15 Service-Parameter-Type AVP
The Service-Parameter-Type AVP is of type Unsigned32 (AVP Code TBD)
and defines the type of the service event specific parameter (e.g. it
can be end-user location, contents provider Id, tax percentage). The
different parameters and their types are service specific and the
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meanings of these parameters are defined between the service element
and the Credit Control Server.
4.16 Service-Parameter-Value AVP
The Service-Parameter-Value AVP is of type UTF8String (AVP Code TBD)
and contains the value of the service parameter type.
4.17 Subscription-Id AVP
The Subscription-Id AVP (AVP Code TBD) is used to identify the end
userÆs subscription and is of type Grouped. The Subscription-Id AVP
includes a Subscription-Id-Data AVP that defines the identifier type
and a Subscription-Id-Type AVP that holds the identifier.
It has the following ABNF grammar:
<Subscription-Id>::=< AVP Header: TBD >
{ Subscription-Id-Data }
{ Subscription-Id-Type }
4.18 Subscription-Id-Data AVP
The Subscription-Id-Data AVP (AVP Code TBD) is used to identify the
end-user and is of type UTF8String. The Subscription-Id-Type AVP
defines which type of identifier is used.
4.19 Subscription-Id-Type AVP
The Subscription-Id-Type AVP (AVP Code TBD) is of type Enumerated and
it is used to determine which type of identifier that is carried by
the Subscription-Id AVP.
The identifier can be one of the following:
END_USER_MSISDN 0
The identifier is in international MSISDN format, according
to the ITU-T E.164 numbering plan as defined in [E164] and
[CE164].
END_USER_IMSI 1
The identifier is in international IMSI format, according to
the ITU-T E.212 numbering plan as defined in [E121] and
[CE121].
END_USER_SIP_URL 2
The identifier is in the form of a SIP URL as defined in
[SIP].
END_USER_NAI 3
The identifier is in the form of a Network Access Identifier
as defined in [NAI].
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END_USER_PRIVATE 4
The Identifier is a credit control server private identifier.
4.20 Unit-Type AVP
The Unit-Type AVP is of type Enumerated (AVP Code TBD) and contains
the type of the unit.
The unit type can be one of the following:
SERVICE_CREDIT_TIME 0
The unit is of type time, given in seconds.
SERVICE_CREDIT_VOLUME 1
The unit is of type volume, given in kB.
SERVICE_CREDIT_EVENT 2
The unit is of type event, given as a number of events.
SERVICE_CREDIT_MONEY 3
The unit is of type money, given as a monetary value, whose
currency SHOULD be specified by the Currency-Code AVP.
4.21 Unit-Value AVP
Unit-Value AVP is of type Float64 (AVP Code TBD) and contains the
granted or used Unit-Value. The value can be time in seconds, volume
in kB, number of events or monetary amount depending on the given
Unit-Type.
If the Unit-Type AVP is set to time in the Accounting-Answer command,
the Unit Value AVP specifies the granted time in seconds (measured
from the moment when the services becomes active or from the previous
Answer command) until a new Accounting-Request MUST be sent.
If the Unit Type AVP is set to time in the Accounting-Request
command, the Unit-Value AVP specifies the used time since previous
report or time requested by the credit control client.
If the Unit-Type AVP is set to volume in the Accounting-Answer
command, the Unit-Value AVP specifies the granted volume in kB
(measured from the moment when the services becomes active or from
the previous Answer command) until a new Accounting-Request MUST be
sent.
If the Unit-type AVP is set to volume in the Accounting-Request
command, the Unit-Value AVP specifies the used volume since previous
report or volume requested by the credit control client.
If the Unit-Type AVP is set to event in the Accounting-Answer
command, the Unit-Value AVP specifies the granted number of events
(measured from the moment when the service becomes active or from the
previous Answer command) until a new Accounting-Request MUST be sent.
If the Unit-type AVP is set to event in the Accounting-Request
command, the Unit-Value AVP specifies the used number of events since
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previous report or number of events requested by the credit control
client.
If the Unit-Type AVP is set to money in the Accounting-Answer
command, the Unit-Value AVP specifies the granted monetary amount,
which the end user can use until a new Accounting-Request MUST be
sent.
If the Unit-Type AVP is set to money in the Accounting-Request
command, the Unit-Value AVP specifies the used monetary amount since
previous report or the monetary amount requested by the Credit
control Client.
4.22 Used-Service-Unit AVP
The Used-Service-Unit AVP is of type Grouped AVP (AVP Code TBD) and
contains the amount of used units since the previous Accounting-
Answer command. The included Unit-Type AVP defines the type of the
unit and the Unit-Value AVP contains the used amount. If the unit
type is money, a Currency-Code AVP SHOULD be included.
It has the following ABNF grammar:
<Used-Service-Unit>::=< AVP Header: TBD >
{ Unit-Type }
{ Unit-Value }
[ Currency-Code ]
5 Result Code AVP values
This section defines new Result-Code AVP [DIAMBASE] values that must
be supported by all Diameter implementations that conform to this
specification.
The Accounting-Answer message includes the Result-Code AVP, which MAY
indicate that an error was present in the Accounting-Request message.
A rejected Accounting-Request message SHOULD cause the userÆs session
to be terminated.
5.1 Transient Failure
Errors that fall within the transient failures category are used to
inform a peer that the request could not be satisfied at the time it
was received, but MAY be able to satisfy the request in the future.
DIAMETER_END_USER_SERVICE_DENIED 40XX
The credit control server denies the service request due to
service restrictions or limitations related to the end-user, for
example the end-userÆs account could not cover the requested
service.
DIAMETER_CREDIT_CONTROL_NOT_APPLICABLE 40XX
The credit control server determines that the service can be
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granted to the end user but no further credit control is needed
for the service (e.g. service is free of charge).
5.2 Permanent Failures
Errors that fall within permanent failure category are used to inform
the peer that the request failed, and should not be attempted again.
DIAMETER_END_USER_NOT_FOUND 50XX
The specified end user could not be found in the Credit Control
Server.
6 AVP Occurrence Table
The following table presents the AVPs defined in this document, and
specifies in which Diameter messages they MAY, or MAY NOT be present.
Note that AVPs that can only be present within a Grouped AVP are not
represented in this table.
The table uses the following symbols:
0 The AVP MUST NOT be present in the message.
0+ Zero or more instances of the AVP MAY be present in the
message.
0-1 Zero or one instance of the AVP MAY be present in the
message. It is considered an error if there are more than
once instance of the AVP.
1 One instance of the AVP MUST be present in the message.
1+ At least one instance of the AVP MUST be present in the
message.
6.1 Accounting AVP Table
The table in this section is used to represent which Credit Control
applications specific AVPs defined in this document are to be present
in the accounting messages.
+-----------+
| Command |
| Code |
|-----+-----+
Attribute Name | ACR | ACA |
------------------------------|-----+-----+
Abnormal-Termination-Reason | 0-1 | 0 |
Accounting-Correlation-Id | 0-1 | 0 |
Credit-Control-Failure- | 0-1 | 0-1 |
Handling | | |
Check-Balance-Result | 0 | 0-1 |
Cost-Information | 0 | 0-1 |
Direct-Debiting-Failure- | 0-1 | 0 |
Handling AVP | | |
Final-Unit-Indication | 0 | 0-1 |
Granted-Service-Unit | 0 | 0+ |
Requested-Action | 0-1 | 0 |
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Requested-Service-Unit | 0-1 | 0 |
Re-Transmission | 0-1 | 0 |
Service-Parameter-Info | 0+ | 0 |
Subscription-Id | 0-1 | 0-1 |
Used-Service-Unit | 0+ | 0 |
------------------------------|-----+-----+
7 IANA Considerations
This section contains the namespaces that have either been created in
this specification, or the values assigned to existing namespaces
managed by IANA.
7.1 Command Codes
This specification uses the value 271 from the Command code namespace
defined in [DIAMBASE].
7.2 AVP Codes
This specification assigns the values TBD - TBD from the AVP code
namespace defined in [DIAMBASE] See section 4.0 for the assignment of
the namespace in this specification.
7.3 Result-Code AVP Values
This specification assigns the values 40XX and 50XX from the Result-
Code AVP (AVP Code 268) value namespace defined in [DIAMBASE]. See
section 5.0 for the assignment of the namespace in this
specification.
7.4 Abnormal-Termination-Reason AVP
As defined in Section 4.1, the Abnormal-Termination-Reason AVP (AVP
Code TBD) defines the values 0-1. All remaining values are available
for assignment via Designated Expert [IANA].
7.5 Check-Balance-Result AVP
As defined in Section 4.3, the Check-Balance-Result AVP (AVP Code
TBD) defines the values 0-1. All remaining values are available for
assignment via Designated Expert [IANA].
7.6 Credit-Control-Failure-Handling AVP
As defined in Section 4.6, the Credit-Control-Failure-Handling AVP
(AVP Code TBD) defines the values 0-1. All remaining values are
available for assignment via Designated Expert [IANA].
7.7 Direct-Debiting-Failure-Handling AVP
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As defined in Section 4.8, the Direct-Debiting-Failure-Handling AVP
(AVP Code TBD) defines the values 0-1. All remaining values are
available for assignment via Designated Expert [IANA].
7.6 Requested-Action AVP
As defined in Section 4.11, the Requested-Action AVP (AVP Code TBD)
defines the values 0-3. All remaining values are available for
assignment via Designated Expert [IANA].
7.7 Subscription-Id-Type AVP
As defined in Section 4.17, the Subscription-Id-Type AVP (AVP Code
TBD) defines the values 0-4. All remaining values are available for
assignment via Designated Expert [IANA].
7.8 Unit-Type AVP
As defined in Section 4.20, the Unit-Type AVP (AVP Code TBD) defines
the values 0-3. All remaining values are available for assignment via
Designated Expert [IANA].
7.9 Application Identifier
This specification assigns the value TBD to the application
Identifier namespace defined in [DIAMBASE]. See section 1.3 for more
information.
8 Credit Control Application related parameters
Tx timer
The Tx timer controls the termination of credit control session in
client in the PENDING state. The recommended value is 10 seconds.
9 Security Considerations
The security models as defined in the Diameter base protocol
[DIAMBASE] applies to this application too.
10 References
10.1 Normative
[DIAMBASE] P. Calhoun, J. Arkko, E. Guttman, G Zorn, J Loughney
"Diameter Base Protocol", draft-ietf-aaa-diameter-11.txt,
IETF work in progress, June 2002.
[3GPPCHARG] 3rd Generation Partnership Project; Technical Specification
Group Services and System Aspects, Service aspects;
Charging and Billing, (release 5), 3GPP TS 22.115 v. 5.1.1,
2001-06
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INTERNET-DRAFT Diameter Credit Control Application June, 2002
[SIP] M. Handley, H. Schulzrinne, E. Schooler, J. Rosenberg.
"SIP: Session Initiation Protocol",
draft-ietf-sip-rfc2543bis-09.txt, IETF work in progress,
February 2002.
[NAI] Aboba, Beadles "The Network Access Identifier." RFC 2486.
January 1999.
[E164] Recommendation E.164/I.331 (05/97): The International
Public Telecommunication Numbering Plan. 1997.
[CE164] Complement to ITU-T Recommendation E.164 (05/1997):"List of
ITU-T Recommendation E.164 assigned country codes", June
2000.
[E212] Recommendation E.212 (11/98): The international
identification plan for mobile terminals and mobile users.
1998.
[CE212] Complement to ITU-T Recommendation E.212 (11/1997):" List
of mobile country or geographical area codes ", February
1999.
[IANA] Narten, Alvestrand, "Guidelines for Writing an IANA
Considerations Section in RFCs", BCP 26, RFC 2434, October
1998
10.2 Non-Normative
[KEYWORDS] S.Bradner, "Key words for use in RFCs to Indicate
Requirement Levelsö, BCP 14, RFC 2119, March 1997.
[ACCMGMT] B.Aboba, J.Arkko, D.Harrington. "Introduction to Accounting
Management", RFC 2975, October 2000.
11 Acknowledgement
The authors would like to thank Paco Marin at Vodafone R&D and our
colleagues with Ericsson and Nokia for their comments and
suggestions.
12 Author's Address
Harri Hakala
Oy L M Ericsson Ab
Joukahaisenkatu 1
20520 Turku
Finland
Phone: +358 2 265 3722
EMail: Harri.Hakala@ericsson.fi
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INTERNET-DRAFT Diameter Credit Control Application June, 2002
Leena Mattila
Oy L M Ericsson Ab
Joukahaisenkatu 1
20520 Turku
Finland
Phone: +358 2 265 3731
EMail: Leena.Mattila@ericsson.fi
Juha-Pekka Koskinen
Nokia Networks
Hatanp„„nvaltatie 30
33100 Tampere
Finlad
Phone: +358 7180 74027
Email: juha-pekka.koskinen@nokia.com
13 Full Copyright Statement
Copyright (C) The Internet Society (2002). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this docu-
ment itself may not be modified in any way, such as by removing the
copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English. The limited permissions granted above are perpetual and will
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This document and the information contained herein is provided on an
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TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
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14 Expiration Date
This memo is filed as <draft-hakala-diameter-credit-control-03.txt>
and expires in December 2002.
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