SIST-TP ETSI/TR 101 734 V1.1.1:2005

• Abstract:

  In the today s Internet there is no collection of charges implemented. Users are charged by the Internet Service Provider (ISP) either a fla

• Status: Published
• Publication Date: 31-Dec-2004
• ICS: 33.040.35 - Telephone networks
• Technical Committee: SPN - Services and Protocols for Networks
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Jan-2005
• Due Date: 01-Jan-2005
• Completion Date: 01-Jan-2005
• Ref Project: ETSI TR 101 734 V1.1.1 (1999-09) - Internet Protocol (IP) based networks; Parameters and mechanisms for charging

SIST-TP ETSI/TR 101 734 V1.1.1:2005 is the Slovenian version of ETSI Technical Report TR 101 734 on Internet Protocol (IP) based networks and charging. It gives guidance on which parameters to collect and which mechanisms to use when charging for IP-based services, aimed at network operators and service providers that need to measure usage, reserved resources, and service characteristics. The report stays on the technical side of metering and record handling, while billing, tariffing, and accounting are treated as separate functions.

What does SIST-TP ETSI/TR 101 734 V1.1.1:2005 specify?

SIST-TP ETSI/TR 101 734 V1.1.1:2005 specifies a technical framework for charging in IP-based networks. It focuses on how to select charging parameters and how to collect charging information, rather than on how to price services or issue invoices.

The report concentrates on the IP-based service component of a user’s charge. It explicitly separates that from charges for content and for access, because in practice those may be handled by different providers.

The document is organized into these main parts: scope, references, definitions and abbreviations, reference configuration, charging principles, charging parameters, and charging mechanisms. Annex A gives an example charging record, Annex B gives an example charging record using MPLS, and Annex C gives a reference implementation.

Annex	What it covers
A	Example of a charging record
B	Example of a charging record using MPLS
C	Reference implementation

What are the key requirements of SIST-TP ETSI/TR 101 734 V1.1.1:2005?

SIST-TP ETSI/TR 101 734 V1.1.1:2005 is mainly a guidance document, so its value is in the charging model, the parameter set, and the measurement approach it describes. The points below are the ones most useful when designing or assessing an IP charging system.

Charging model and service assumptions

• The report separates charging into content, access, and IP-based service. In practice, this helps an operator decide exactly which part of the service chain needs to be measured and settled.
• It allows several provider relationships across layers: each provider may bill the user directly, one provider may bill on behalf of others, or one provider may buy the service from another. In practice, this is the basis for inter-operator revenue accounting.
• It assumes multiple charging principles may coexist and that charges can combine setup, periodic, and usage-based elements. In practice, a charging design may need more than one tariff element for the same service.
• It treats charge prediction as a separate topic. In practice, that means the report is about collecting the data needed for charging, not about how to present final prices to the user.

Service types, sessions, and phases

• The report discusses three IP service types: best effort, controlled load, and guaranteed service. In practice, the chosen service class affects whether reservation data, delay, loss, or resource allocation need to be recorded.
• It uses the concepts of session and phase. A session is the overall communication period, and a phase is a period in which traffic characteristics stay fixed. In practice, meters need clear start and stop points and also need to detect when traffic conditions change.
• It links higher-quality services to RSVP and DIFFSERV, with lower-layer support where needed. In practice, charging may depend on reservation and priority information, not only on bytes transferred.

Parameters to collect

• Clause 6 divides charging data into subscription parameters and communication parameters. In practice, this is the core selection step for a charging implementation.
• Subscription parameters include access type, physical characteristics, maximum available bandwidth, and maximum number of connections or flows. In practice, these describe what the subscriber is entitled to before any traffic is carried.
• Communication parameters include fixed-per-session items such as service type, session start time, and user ID, plus flow-related items such as partner, duration, time of day, priority, provided Quality of Service (QoS), traffic contract parameters, reserved resources, actual volume used, and multipoint aspects. In practice, these are the values a meter or reader has to capture from live traffic.
• The report says the values should be collected for each direction of communication separately. In practice, upstream and downstream usage may need separate counters and records.
• It highlights reserved resources and actual usage as different charging bases. In practice, an operator may charge for reservation even when the reserved capacity is not fully used.
• For multicast, it adds sender and receiver counts, individual reservation parameters, and individual QoS for receivers or tree segments. In practice, charging logic has to support cost sharing and heterogeneous service quality within one group.

Charging mechanisms and measurement points

• Clause 7 describes a charging entity with measuring, record generation, storage, storage-capacity checking, timing, data communication, availability control, and performance monitoring functions. In practice, a charging system is more than a counter - it also has to store and forward records reliably.
• The report places the technical measurements at the IP layer, not at higher user-plane layers, and says they should take place at border routers of the provider network. In practice, this defines where metering equipment should be installed.
• It distinguishes meter, reader, charging, and billing functions, with interfaces for configuration, policy, and data transfer. In practice, that separation helps engineers design systems in modules rather than as one monolithic recorder.

What terms does SIST-TP ETSI/TR 101 734 V1.1.1:2005 define?

• Accounting - revenue sharing amongst operators, also called settlement or revenue accounting.
• Billing - the process of turning stored charging information into a bill for a user.
• Charging - determining the charge units to assign to service use.
• Flow - a unidirectional communication relation for one service and one interaction, from start of transfer until end or interruption.
• IntServ Flow - a unidirectional IP packet flow for which an Integrated Services (IntServ) Resource Reservation Protocol (RSVP) reservation is valid.
• Metering - measuring charge-related components such as duration or usage, also called collection of charging information.
• Phase - a period within a session in which traffic characteristics do not change.
• Session - a communication relation with a clear start and end point, used as a billable event in charging.

Who uses SIST-TP ETSI/TR 101 734 V1.1.1:2005?

SIST-TP ETSI/TR 101 734 V1.1.1:2005 is used by network operators, service providers, and teams that design charging or accounting functions for IP-based services. It is also relevant to engineers working on metering, reader functions, record formats, and inter-operator revenue sharing.

In practice, it helps people who need to decide:

• which traffic and service parameters should be measured
• where to place measurement functions in the network
• how to structure charging records
• how to support services such as RSVP-based or Differentiated Services (DIFFSERV) traffic
• how to handle multicast charging and multi-provider scenarios

Which standards are used with SIST-TP ETSI/TR 101 734 V1.1.1:2005?

The report builds on earlier ETSI and IETF work on charging, reservations, flow measurement, and QoS.

Reference	What it contributes
ETR 123	Background on parameters and mechanisms for charging in B-ISDN
TR 101 619	Definitions for accounting, billing, tariffing, and related charging terms
IETF RFC 1889	Real-Time Transport Protocol (RTP) for real-time traffic
IETF RFC 2205 and RFC 2208	RSVP specification and deployment guidance
IETF RFC 2475	Differentiated Services architecture
ITU-T E.164	Numbering plan used as an example for user ID
IETF RFC 1700	Assigned numbers, used in Annex B
IETF RFC 2063, RFC 2064, RFC 2123	Traffic Flow Measurement architecture, meter MIB, and implementation experience
IETF RFC 2212, RFC 2213, RFC 2214, RFC 2215	Integrated Services QoS and management information bases
IETF RFC 2382	Framework for Integrated Services and RSVP over ATM
[17] and [18]	Traffic accounting and NeTraMet/NeMaC experience used for examples and implementation ideas

What does the SIST-TP ETSI/TR 101 734 V1.1.1:2005 document contain?

The document contains a reference configuration for how charges flow across access networks, IP-based networks, and service layers. It also contains a charging reference model with meter, reader, charging, and billing functions, plus policy and configuration interfaces.

Table 1 lists subscription-related parameters, and Table 2 lists communication-related parameters with applicability notes for sessions, flows, IntServ, and DIFFSERV. Annex A and Annex B give record formats that can be used when designing charging data structures, while Annex C describes a reference implementation based on RSVP, RTFM, SNMP, and NeTraMet.

SLOVENSKI STANDARD
01-januar-2005
2PUHåMDQDSRGODJLLQWHUQHWQHJDSURWRNROD,3±3DUDPHWULLQPHKDQL]PL
]DUDþXQDYDQMD
Internet Protocol (IP) based networks; Parameters and mechanisms for charging
Ta slovenski standard je istoveten z: TR 101 734 Version 1.1.1
ICS:
33.040.35 Telefonska omrežja Telephone networks
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

Technical Report
Internet Protocol (IP) based networks;
Parameters and mechanisms for charging

2 ETSI TR 101 734 V1.1.1 (1999-09)
Reference
DTR/SPAN-080301 (g2000ics.PDF)
Keywords
Internet, IP, charging
ETSI
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Copyright Notification
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The copyright and the foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1999.
All rights reserved.
ETSI
3 ETSI TR 101 734 V1.1.1 (1999-09)
Contents
Intellectual Property Rights.4
Foreword .4
Introduction .4
1 Scope.5
2 References.5
3 Definitions and abbreviations .6
3.1 Definitions . 6
3.2 Abbreviations. 8
4 Reference Configuration.8
4.1 Network aspect . 8
4.2 Charging reference model. 10
4.3 Service Aspect . 12
5 Charging principles applied to IP based networks.13
6 Parameters relevant for charging in IP based networks.14
6.1 List of parameters . 14
6.2 Description of the parameters . 16
7 Charging mechanisms required in IP based networks .19
Annex A (informative): Example of a charging record .20
Annex B (informative): Example of a charging record using MPLS.21
Annex C (informative): Reference Implementation.24
Bibliography.25
History.26
ETSI
4 ETSI TR 101 734 V1.1.1 (1999-09)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect
of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web server
(http://www.etsi.org/ipr).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in SR 000 314 (or the updates on the ETSI Web server)
which are, or may be, or may become, essential to the present document.
Foreword
This Technical Report (TR) has been produced by ETSI Technical Committee Services and Protocols for Advanced
Networks (SPAN).
Introduction
ETSI has already established an ETSI Technical Report on Parameters and Mechanism for Charging in ATM based
Networks, see ETR 123 [1], produced by former ETSI STC NA5. With the emergence of IP and the trend to use IP not
only for the "best effort" service as it is done today, the question on how to charge such diverse services emerges.
With the background of the work done for ETR 123 [1] the follow up body of ETSI STC NA5, the ETSI WG SPAN8
(formerly NA8) has to prepare a comparable document for IP based services.
ETSI
5 ETSI TR 101 734 V1.1.1 (1999-09)
1 Scope
The present document gives guidance in selecting charging parameters and the appropriate charging mechanisms in the
IP (Internet Protocol) based networks of the future.
In the today's Internet there is no detailed collection of charges implemented. Users are charged by the Internet Service
Provider (ISP) either:
• a flat rate;
• a time dependent rate; or
• a volume class dependent rate.
In addition the telecommunication service to access the ISP is charged by the Telecommunication Network Operator.
Such charging schemes will persist but with the emergence of the Internet - especially with the evolution towards
commercial operation - the need arises to collect charging information for diverse services. These charges may be
composed of various parameters and components according to the service split among several operators. The present
document concentrates on such cases only where parameters are collected.
Therefore, the present document describes a first set of parameters relevant for charging and the mechanisms needed for
collection of charging information in IP based networks. The general principles for charging are listed which apply to IP
based networks. These parameters are applicable to all types of IP based services. Nevertheless an appropriate set of
parameters can be selected for each type.
Collection of charging information will be done both by network operators and service providers for the usage of
resources. The present document describes parameters and mechanisms from a technical point of view. Therefore, the
term "operator" is used throughout the present document where it is applicable to service providers, to network
operators, or to both service providers and network operators.
Accounting, tariffing and billing of IP based services are outside the scope of the present document. Nevertheless these
issues are also of great interest for IP based networks and services. Accounting (or settlement) is currently discussed in
ITU-T Study Group 3 and for the Internet Telephony Service in ETSI Project TIPHON.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
• A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same
number.
[1] ETR 123: "Broadband Integrated Services Digital Network (B-ISDN); Parameters and mechanisms
provided by the network relevant for charging in B-ISDN".
[2] TR 101 619: "Network Aspects (NA): Considerations on network mechanisms for charging and
revenue accounting".
[3] IETF RFC 1889: "RTP: A Transport Protocol for Real-Time Applications"; H.Schulzrinne,
S.Casner, R.Frederick, V.Jacobson; January 1996.
ETSI
6 ETSI TR 101 734 V1.1.1 (1999-09)
[4] IETF RFC 2205: "Resource ReSerVation Protocol (RSVP) - Version 1 Functional Specification",
L. Zhang, R. Braden, S. Berson, S. Herzog, and S. Jamin; September 1997.
[5] IETF RFC 2208: "Resource ReSerVation Protocol (RSVP) Version 1 Applicability Statement
Some Guidelines on Deployment"; A. Mankin, F. Baker, B. Braden, S. Bradner, M. O`Dell,
A. Romanow, A. Weinrib, L. Zhang; September 1997.
[6] IETF RFC 2475 "An Architecture for Differentiated Services"; S.Blake, D.Black, M.Carlson,
E.Davies, Z.Wang, W.Weis; October 1998.
[7] ITU-T Recommendation E.164: "The international public telecommunication numbering plan".
[8] IETF RFC 1700: "Assigned Numbers"; J. Reynolds, J. Postel.
[9] IETF RFC 2063: "Traffic Flow Measurement: Architecture"; N. Brownlee, C. Mills, G. Ruth;
January 1997.
[10] IETF RFC 2064: "Traffic Flow Measurement: Meter MIB"; N. Brownlee, University of Auckland,
New Zealand, January 1997.
[11] IETF RFC 2123: "Traffic Flow Measurement: Experiences with NeTraMet"; N. Brownlee;
March 1997.
[12] IETF RFC 2213: "Integrated Services Management Information Base using SMIv2"; F. Baker,
J. Krawczyk, A. Sastry; September 1997.
[13] IETF RFC 2214: "Integrated Services Management Information Base Guaranteed Service
Extensions using SMIv2"; F. Baker, J. Krawczyk, A. Sastry; September 1997.
[14] IETF RFC 2215: "General Characterization Parameters for Integrated Service Network Elements";
S. Shenker, J. Wroclawski; September 1997.
[15] IETF RFC 2382: "A Framework for Integrated Services and RSVP over ATM"; E. Crawley
L. Berger, S. Berson, F. Baker, M. Borden, J. Krawczy; August 1998.
[16] IETF RFC 2212: "Specification of Guaranteed Quality of Service"; S. Shenker, C. Partridge,
R. Guerin; September 1997.
[17] M. Canosa, M. De Marco, A. Maiocchi: "Traffic Accounting Mechanisms for Internet Integrated
Services", In Proceedings of SPIE VV'98, Vol. 3529 Internet Routing and Quality of Service,
Boston, Massachusetts, 1.-6. November , 1998.
[18] A. Maiocchi: "NeTraMet & NeMaC for IIS Accounting: User’s Guide", CEFRIEL, Politecnico di
Milan, May 1998.
3 Definitions and abbreviations
3.1 Definitions
Many definitions relevant for the present document are already contained in ETSI TR 101 619 [2]. The most important
ones are repeated here.
For the purposes of the present document, the following definitions apply:
Accounting: revenue sharing amongst operators.
NOTE 1: Also known as "settlement" and "revenue accounting".
Billing: process of transferring the stored charging information for a user into a bill. [TR 101 619 [2]]
Charging: the determination of the charge units to be assigned to the service utilization (i.e. the usage of chargeable
related elements). [TR 101 619 [2]]
ETSI
7 ETSI TR 101 734 V1.1.1 (1999-09)
Content provider: entity which offers information to the user.
Flow: unidirectional communication relation from one user to another user dedicated to and established for the transfer
of data belonging to one service and one interaction, started by a trigger and terminated by the end of the data transfer or
an interruption (e.g. transfer of a file via ftp).
NOTE 2: The flow start time is the time when the first packet is sent. The flow ends if no more packets are sent for
a pre-defined time interval (maximum allowed flow idle time). (See also IntServ Flow.)
IntServ Flow: unidirectional flow of IP packets for which in an IntServ (RSVP) reservation is valid.
NOTE 3: Since RSVP allows senders to share a reservation (resource) a flow can have multiple source addresses
(one flow per session). For unicast sessions or if a distinct reservation is made, the flow has only one
sender. An IntServ flow is defined by its source address(es), optional source port, destination address and
destination port [15].
Metering: The measurement of "components" which can be used for charging such as the duration of the call. In the
present document named also "collection of charging information".
Network charging capabilities: a set of procedures performed by the network elements in order to determine all the
parameters of one communication session, which are required for assessing the effort provided by the network, and to
determine the values of these parameters.
Network layer service: the provision of resources by the network for the transmission of data.
NOTE 4: To provide services above the best effort delivery the mechanisms of the Integrated Services or the
Differentiated Services Model can be used.
Network Operator: entity which is operating a public telecommunication network. If local networks are operated the
network operator can provide access for subscribers and users. [TR 101 619 [2]]
Pricing: the correlation between "money" and "goods" or "service".
NOTE 5: The term is not generally used in telecommunications, the usual term being "tariffing".
Service provider: entity that can provide a service to a user having established a call by a network operator. The
network operator may be the service provider. [TR 101 619 [2]]
Phase: period within a session in which the traffic characteristics do not change.
NOTE 6: A new phase is entered if the reservation parameters are renegotiated.
NOTE 7: If a session can consist of multiple flows, the traffic characterization can be different for each flow. A
phase specifies a period of a session or a period of a flow. Since charging parameters (like price per time
unit or length of a measurement interval) can depend on the time of day, the entering of a new time period
(e.g. business hours) might be also considered as the entering of a new phase.
Revenue accounting: technical process of accounting the collected revenue for joint service provision to a group of
users and distributing it to the interworking and/or co-operating service/network providers. [TR 101 619 [2]]
RSVP session: session (data flow) defined by destination address (unicast or multicast), optionally destination port
number and the protocol ID of the transport-layer protocol [4].
NOTE 8: For multicast communication a destination port is not mandatory. For unicast communication a destination
port number should be specified in order to distinguish several unicast sessions to the same hosts.
Service: That which is traded by a provider.
Service subscriber: entity, i.e. a user-identity, which subscribes to a service offered by the service provider.
Session: communication relation between one user and another or other users, characterized by a clearly defined starting
point and a clear defined termination point (e.g. login and logout - see also RSVP session definition).
ETSI
8 ETSI TR 101 734 V1.1.1 (1999-09)
NOTE 9: An internet session could be seen as when a connection is opened between an email reader and a POP3
email server or when a user dials up an ISP in order to browse the WWW. More complicated sessions are
for example multiparty interactive video conference over a broadband internet. The key point regarding a
session, from the perspective of charging, is that it provides an opportunity for use coupled with start and
end points in order to create a billable event.
Tariff: charged price per usage element or per group of usage elements. [TR 101 619 [2]]
Tariffing: determination of the prices to be applied for services and service elements. [TR 101 619 [2]]
User: entity which actually uses a service.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ATM Asynchronous Transfer Mode
B-ISDN Broadband Integrated Services Digital Network
CL Connectionless
DIFFSERV Differentiated services
DS Differentiated Services (field)
ID Identification
IntServ Integrated services
IP Internet Protocol
ISP Internet Service Provider
MAN Metropolitan Area Network
MIB Management Information Base
MPLS Multi Protocol Label Switching
N-ISDN Narrowband Integrated Services Digital Network
OS Operations System
PHB Per Hop Behaviours
POP3 Post Office Protocol, Version 3
QOS Quality of Service
RRouter
RSVP Resource Reservation Protocol
RTFM Real Time Flow Measurement
RTP Real-Time Transport Protocol
SLA Service Level Agreement
SNMP Simple Network Management Protocol
SRL Simple Ruleset Language
SW Switching System
TOS Type of Service (field)
TR Technical Report
WWW World Wide Web
XC Cross Connect
4 Reference Configuration
4.1 Network aspect
Figure 1 shows the reference configuration of the network the further considerations are based on as well as the flow of
charges. It consists of an Access Network to the IP based network and the IP based network itself.
ETSI
9 ETSI TR 101 734 V1.1.1 (1999-09)
User Server
(A-side) (B-side)
Access Access
IP based
Network Network
Network
charges for
access
charges for IP
based service
charges for
content
charges for
access (B-side)
charges for IP based
service (B-side)
NOTES:
One operator might operate more than one of the networks shown.
The shown networks might consist of a concatenation of several networks of the same type.
The server is shown to represent the usual usage of the Internet. It might also be a second user.
The B-side can also be a gateway in case of "Internet Telephony".
Figure 1: Reference configuration and charges
The user is charged for several components of his communication (which are usually provided by several operators)
such as:
• charges for the content (to be paid to the content providers);
• charges for the access to the network (to be paid to the access network operator);
• charges for the IP based service (to be paid to the operator of the IP based network).
There might be other components and other operators/providers. The present document concentrates only on the third
component: the IP based network (the third bullet).
Usually each of the above mentioned networks is composed of several networks operating on different layers. This
principle is shown in Figure 2.
ETSI
10 ETSI TR 101 734 V1.1.1 (1999-09)
IP Layer
logical
R
R
connection
Option 2 and 3:
In case these
Layers are
The user is either
operated by
charged by each
different operators
operator (Option 1)
the lower layer
Transport Layer
or by one of them
operator charges
(Options 2 and 3).
( e.g. ATM) the upper layer
SW
SW
operator.
(revenue
accounting)
physical
XC
XC
connection
R = Router
Transmission Layer
XC = Cross Connect
SW = Switching System
NOTE: The shown layers may consist of a concatenation of several networks operating at this layer.
Figure 2: Principle of charging between layers
The commercial interrelationship between the providers presets a number of alternatives, e.g.:
1) Every provider charges the end-user individually. This requires that the providers one by one can identify the
end-user or in other words: the user is customer of several providers.
2) One provider charges the end user on behalf of all providers. This requires revenue accounting later. The user
is still customer of several providers but only one of them (usually the one operating the highest layer in
consideration) charges him.
3) One provider buys the service from the other providers. This makes the end-user charging simple. The user is
only a customer of one of the providers.
Options 2 and 3 need "charging between layers" which means revenue accounting between individual providers. In
option 2 this can be done off line, which means not necessarily during the session.
4.2 Charging reference model
The relationship between all actions related to charging is shown in Figure 3. Three main areas can be distinguished:
• the area with strategic and market relevance - this relates to tariffing;
• the area with administrative relevance - this relates to charging, accounting and billing;
• the area with technical relevance - this relates to the collection of parameters for charging.
ETSI
11 ETSI TR 101 734 V1.1.1 (1999-09)
Sending a Revenue
bill to the Billing Accounting sharing with
customer other operators
Area with
Charging
administrative
relevance
Reading of the
Parameters
Area with
Tariffing technical
Metering of
relevance
Parameters for
Area with
Charging
strategig and
market relevance
Network
Figure 3: Relationship between the different tasks in the charging/accounting/billing process
A corresponding reference model for classifying functional entities required for charging in IP based networks, and for
describing their interaction is shown in Figure 4. The left part of the figure represents the policy part i.e. the commercial
intelligence in which the parameters currently are decided based on the market situation (i.e. tariffing policies, reader
policies and metering policies). The parameters are added as temporary data to the layers in the right part of the figure
through the configuration plane. The right part of the figure represents the four different functional layers of the
charging machinery that encompass processing of data relevant for charging.
Customer Specific
Billing
Tariffing Parameters
Tariffing and
Service Specific
Policy Accounting
Tariffing Parameters
Layer
Accounting
Parameters
Charging Layer
Con-
figu-
rat-
C&R-PI C&R-DI
ion
Reader
Reader Reader Layer
Parameters Plane
Policy
MR-CI
R&M-PI
R&M-DI
Metering
Metering Metering Layer
Parameters
Policy
M-CI
C&R -DI Reader / Accounting Data Interface R&M-DI Metering / Reader Data Interface
R-CI Reader Configuration Interface M-CI Metering Configuration Interface
C&R-PI Reader / Accounting Policy Interface R&M-PI Metering / Reader Policy Interface
Figure 4: Charging and accounting reference model with policy interfaces, configuration interfaces
and data interfaces
ETSI
12 ETSI TR 101 734 V1.1.1 (1999-09)
The metering layer specifies functional entities for metering of resource usage or recording and counting of charge
related events. Metering permits distinction between reservation of network resources, and actual usage of network
resources. This distinction is useful as resources that are reserved but not used by a user may be offered to a different
user, but usually under different conditions (lower price). Charging schemes may reflect this difference, e.g. by charging
separately for reservation, and for actual usage.
The reader layer encompasses functional entities that access data provided by metering entities via the Metering and
Reader Data Interface (R&M-DI) and forward it for further processing to the charging layer. For supporting multicast
charging, this layer can select appropriate meters. Transfer of metering data to the reader can be initiated explicitly (the
reader initiates transfer of metering data) or implicitly (after a triggering event such as detection of a new flow, the meter
initiates transfer of metering data to the reader).
Entities of the charging layer process usage data that has been collected by meter readers, try to consolidate it based on
service parameters and create accounting data sets, or accounting records, which are passed via the Reader and
Charging Data Interface (C&R-DI) to the charging layer for the assignment of prices. For support of multicast charging,
the multicast topology including splitting points can be reconstructed by entities of this layer, supporting algorithms such
as cost sharing between receivers. In a multi-provider environment, entities of this layer can distribute collected usage
data to other domains. A simple evaluation of current costs can be used to display an estimation of accumulated costs for
the service user, or for control purposes by the customer organization or by the provider. For charging of multicast services,
algorithms for cost allocation can assign costs to specific endpoints, such as sender(s) and receivers of a multicast group.
Entities of the billing and accounting layer translate costs calculated by the charging layer into monetary units and
generate bills for the customers and clearing information to other operators involved in the communication. Algorithms
of the billing and accounting layer may combine technical considerations with economic considerations, such as volume
of resources used by the customers, and marketing methods (e.g. offering discounts).
Annex C shows a reference implementation using RSVP.
The rest of the document only considers the parameters which can be used in the metering layer.
4.3 Service Aspect
The Internet Protocol is connectionless in its nature and currently supports only a service type which does not guarantee
any Quality of Service. This is called "best effort" service. With the emerging of applications which need a kind of
guarantee (so called Real Time Services) new mechanisms are necessary. The answers of the Internet Community were
the Real Time Protocol (RTP) [3] and the Resource Reservation Protocol (RSVP) [4] associated with mechanisms to
manage the resources in network elements.
In the evolution from today's Internet to an IP based multiservice network
...