1. Policy-based Accounting: Accounting Issues Georg Carle, Sebastian Zander, Tanja Zseby GMD FOKUS - German National Research Center for Information Technology [carle, zander, zseby]@fokus.gmd.de http://www.fokus.gmd.de/glone/ http://www.fokus.gmd.de/usr/carle

2. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 2 Overview Accounting requirements Derived issues Policy-based accounting draft-irtf-aaaarch-pol-acct-00.txt Accounting architecture with policy translation  Tanja Zseby –relation to other accounting work –Examples –Next steps and open issues

3. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 3 Accounting Requirements Variety of Provider Characteristics –Size and Purpose (e.g. small ISP, large backbone operator) –QoS provisioning technique (e.g. DiffServ, IntServ) –Service classes –Charging scheme(s) and models –Accounting Services –Accounting agreements with other providers (e.g. data exchange, distribute tasks) –Existing heterogeneous Infrastructure (MIBs, profile meters, etc.)  hide heterogeneity Variety of User Profiles –Number of flows, flow granularity, traffic profiles, unicast/multicast –User preferences (e.g. acc. indication, itemized invoices, spending limits) Support Distribution of accounting tasks among different entities –Provisioning of accounting service by other providers, and also to users

4. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 4 Accounting Issues Flexibility: support specific accounting functionality, depending on service, tariff, user, accounting target with rich functionality: accounting for (1) usage metering and charging, (2) QoS auditing, (3) others (traffic engineering, non- repudiation of service usage,...) Outsourcing - Accounting as separate service: exchange of accounting information between different providers, and to customer. Interoperability: intra-domain, inter-domain, to user. Abstraction: desire to use variety of metering devices while hiding heterogeneity Interaction of Accounting with Authentication and Authorisation Privacy: Restrict access to accounting information Scalability and Efficiency

5. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 5 Policy based Accounting Service Accounting configurability needed for different services/users/tariffs/targets Accounting service allows outsourcing of functionality Need for usage accounting and QoS auditing Consumers of accounting service: ISPs, content providers, users =>Intra-Domain Acct., Inter-Domain Acct., User Acct. Indication Accounting policies specify generation, transport and storage of acct. data AS 2 AS 3 AAA Server AAA Server AS 1 User M M AAA Server M M M Content provider Acct. Policy Database Acct. Policy Database

6. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 6 Policy-based Accounting: Addressing the Issues Flexibility –Make accounting components configurable  use of accounting policies –Define common configuration interfaces for different types of accounting components (e.g. different meter types) –Re-Use existing components (MIBs, admission control functions) Outsourcing + Abstraction –Relation of service and accounting functionality: (1) accounting as part of the service; (2) accounting as a service –Accounting primitives for specifying accounting service (-> accounting policies; needs accounting support by policy language) Interaction with Authorization + Privacy –Use authorization data bases, messages, languages, etc. –Authorize accounting services (e.g. online charging, itemized invoice) –Support accounting authorization policies. Scalability + Efficiency –Perform metering and accounting at most appropriate location on the path –Control allocation of resources for accounting –Adapt accounting components to specific accounting service (required parameters, meter accuracy)

7. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 7 Draft: Policy-based accounting draft-irtf-aaaarch-pol-acct-00.txt (Carle/Zander/Zseby) –Roles and relations between roles –Reference Model and Building Blocks –Accounting Policies –Accounting Services –Integrated Accounting / Discrete Accounting –Intra-Domain Accounting /Inter-Domain Accounting / Accounting Indication –Integration of Accounting Services in Authorization Model: Agent Sequence, Pull Sequence, Push Sequence –Examples: Intra-Domain / Inter-Domain Accounting, –Accounting/Charging Indication, Mobile/Roaming

8. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 8 Accounting Serv. ASM Policy based Accounting Architecture ASM Accounting Configuration AAA Server AAA Server AAA Server configuration Acct. Policy Datab. Meter Configuration Meter Conf. Datab. Acct.policies QoS Auditing. policies User profiles Acct. Authent. policies Meter Characteristics Meter resources Meter Meter Reader Accout. Data Accounting Serv. Accounting Consumer Meter data Accounting data

9. August 2, 2000AAAARCH Meeting, IETF Pittsburgh 9 Accounting Policies If condition then action attribute=value set user ID src/dst host/network flow attributes (src, dst, dscp, port,..) service time of day network load individual resource utilization current QoS Record collection: record type report interval report target Meter Instructions: flow granularity (attributes) stored attributes Record Storage: storage time storage format storage location