Telephone Charging System Helsinki University of Technology Yao - PowerPoint PPT Presentation

Telephone Charging System Helsinki University of Technology Yao Yanjun Petteri Tulikoura

Agenda � Introduction � Traditional telephone charging system � Outdated Charging � Charging Nowadays � Future scenarios for charging � Case: IP Telephony � Towards pure-IP networks

Introduction � What is “charging”? “ A function whereby information related to a chargeable operation is formatted and transferred in order to make it possible to determine usage for which the charged party may be billed. ” � What does it focus on? � the generation, formatting and transfer of data records, which provide details relating to the usage of a service or consumption of an item of content.

Traditional Charging System

Charging Systems in the Past � Charging a telephone system with telephone operators. � Counting the number of “pulses” generated per call within the telephone exchanges involved in the setup, routing and control of these calls � The pulse generated per call varied in relation to the location of the callee “pulse is a rapid change in some characteristic of a signal”

Current Charging Systems Call Detail Record (CDR) (also Call Detail Recording) or Station � Message Detail Recording (SMDR) is a record containing information about recent system usage: the identities of sources (points of origin), � the identities of destinations (endpoints), � the duration of each call, � the amount billed for each call, � the total usage time in the billing period, � the total free time remaining in the billing period, � the running total charged during the billing period. � CDRs may be output to a file, may be sent as packets on a network, � or may be output from a serial port on a piece of telecom hardware.

Telephone Network callee Interconnect switch Operator B Transit switch Call Detail Record Charging Calling party 01023422315 system Operator A Called party 05564123444 Call start 02022006:101007 Call end 02022006:101703 Recording unit 22 Residential Record type 01 switch Egress circuit 244 caller Egress port 37

Concepts Charging: Offline charging: charging mechanism where charging information � does not affect, in real-time, the service rendered. Online charging: charging mechanism where charging information � can affect, in real-time, the service rendered and therefore a direct interaction of the charging mechanism with bearer/session/service control is required. Billing: Postpaid billing: pay an insurance payment in advance, the � installation or setup fees, be invoiced (receive a bill) to pay for his usage of the service. Prepaid billing: buys a given amount of credits (duration, volume, � number of events) , corresponds to a real-time process

Charging for Data Charging data record: a formatted collection of information � about a chargeable event (e.g. time of call set-up, duration of the call, amount of data transferred, etc) for use in billing and accounting. 56k modem (nearly obsolete): � � charging on time and/or traffic ADSL: � � month-charged, no charging on time and traffic

Intelligent network The Intelligent Network is a network architecture for both fixed � and mobile telecommunication networks. It allows operators to differentiate themselves by providing value-added services in addition to the standard telecoms services. For example: Call divert � Toll free calls � Prepaid calling � Private number plans � Call screening �

Charging – Case: VoIP Future Scenarios for

VoIP Consumer VoIP Software-based � Skype, MSN, Yahoo � Hard phone � IP telephony service providers � Over broadband Internet services � Normal phone connected through an analog � telephone adapter (ATA) FON is a VoIP service formed by a community � Share your home WiFi with other community � members Get access to VoIP through others’ WiFi when you � are on the move Corporate Corporate bridging � Wireless VoIP Unregulated (802.11x) � Regulated (3G) �

IP Telephony System Client Layer • Analog-to-digital conversion and compression Call Processing Layer • An IP version of PBX Application Layer • Performs call setups and tear-downs • Also performs CAC and conference • Voice mail management • Faxing • Call forwarding • Directory services Infrastructure Layer • Responsible for the delivery of the voice packets • Qos, high availability, and overall network capability crucial

VoIP Benefits for Corporations Traditionally voice traffic through Especially organizations could benefit from IP-based systems circuit-switched PSTN Reduced costs and complexity � � Many organizations may also have because there is only a single their own internal telephone network to manage systems using a private branch � More efficient use of bandwidth exchange (PBX) � Ease of adding and or moving people around because phone � Means deploying a separate numbers are all provisioned in network for data traffic as well as to software rather than pay long-distance charges for calls “hardswitch” connections to remote branches or partners � Reduced long-distance charges (toll bypass)

Challenges in Charging for VoIP Services Quality of service (QoS) is important in IP telephony as it is � critical for voice packets to arrive in the correct order with minimal delay Efficient pricing mechanisms coupled with traditional � congestion control protocols as a solution to congestion control There are great differences among the services offered by � the QoS capable networks Therefore, one might ask whether the prices of these � services should also differ, and if so, how?

VoIP Displacing Traditional PBX Equipments? Worldwide Shipments by Technology Type Gartner’s forecasts for 2008 TDM Line IP Line � 55% of all Premises Switching Equipment (PSE) lines will be pure-IP � TDM/ PBX/KTS lines are expected to drop to a 10% market share by the end of the 2008 � The remaining 90% will be a mixture of pure IP-PBX and IP- enabled shipments Source: Gartner (2004)

VoIP Displacing Traditional PBX Equipments? Expected mix of solutions by technology type over the forecast period PSE Extension Line Forecast PBX Traditional Lines � Traditional solutions will continue to decline rapidly IP-Enabled PBX Traditional Lines � IP enabled solutions will dominate IP-Enabled PBX IP Lines � Pure IP solutions will enjoy rapid growth, but will account only 35% Pure IP PBX Lines of line shipments 2007 Source: Gartner Dataquest (2004)

Conclusions � Telephone systems have evolved from analog circuit-switched networks to IP-based solutions � Telecoms have huge investments in circuit- switched networks � But IP-based solutions are more cost efficient

Reference Sudhir Dixit, Tao Wu: Content Networking in the Mobile � Internet, chapter 12.2 http://en.wikipedia.org/wiki/Call-detail_record � http://en.wikipedia.org/wiki/Pstn � http://en.wikipedia.org/wiki/Intelligent_network � 3GPP TS 32.240, Charging Architecture and Principles, � 09.2004 http://www.ida.gov.sg/idaweb/media/PressRelease_LeadSto � ry_Main.jsp?leadStoryId=L153&versionId=3

Global spending on IP technology will overtake TDM by 2008