Harri Hakala, Leena Mattila INTERNET-DRAFT Ericsson, Draft: 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 works is not granted. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or cite them other than as "work in progress". The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/lid-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html 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. Hakala et al. expires December 2002 [Page 1] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 2] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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. Hakala et al. expires December 2002 [Page 3] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 4] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 5] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 6] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 7] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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. Hakala et al. expires December 2002 [Page 8] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 9] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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. Hakala et al. expires December 2002 [Page 10] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 11] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 12] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 13] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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. Hakala et al. expires December 2002 [Page 14] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 15] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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., Hakala et al. expires December 2002 [Page 16] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 17] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 18] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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, Hakala et al. expires December 2002 [Page 19] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 20] INTERNET-DRAFT Diameter Credit Control Application June, 2002 != 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 | Hakala et al. expires December 2002 [Page 21] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 22] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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: ::=< 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. Hakala et al. expires December 2002 [Page 23] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 24] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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: ::=< 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 Hakala et al. expires December 2002 [Page 25] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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: ::=< 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: ::=< 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 Hakala et al. expires December 2002 [Page 26] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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: ::=< 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]. Hakala et al. expires December 2002 [Page 27] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 28] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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: ::=< 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 Hakala et al. expires December 2002 [Page 29] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 | Hakala et al. expires December 2002 [Page 30] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 31] INTERNET-DRAFT Diameter Credit Control Application June, 2002 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 Hakala et al. expires December 2002 [Page 32] 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 Hakala et al. expires December 2002 [Page 33] 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 not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 14 Expiration Date This memo is filed as and expires in December 2002. Hakala et al. expires December 2002 [Page 34]