1. Telecom OSS/BSS
Overview
Prepared by : Magid Fatehy
Telecom OSS Team Leader at Giza Systems
www.magid.tk

2. Before we Begin
• This presentation is a very high level
overview for the most Telecom OSS/BSS
components.
• Any information or examples in the
presentation are not related to a specific
operator or vendor.
• Any similarity with any implementation is
not intended.

3. Agenda
 General Concepts
 Data Collection
 Mediation
 Billing
 SS7 Monitoring
 Revenue Assurance
 Fraud Management
 Fulfillment / Provisioning
 Number Portability Management

4. General Concepts
 Numbering Plan +20 10 1234567
• + or 00 To dial international number
• 20 Egypt prefix
• 10 Vodafone prefix
• 1234567 Subscriber number

5. Call Scenario
Local Internal Trunks Internal Trunks Local
Loop Loop
Toll Exchange or Tandem Switch : connects multiple switches
to route the calls

6. CDR / EDR / xDR
• CDR: Call Detail Record
• Generally called EDR (E for Event) or xDR
• The switch generate the EDR which contain mainly
• A#: Calling Number
• B#: Called Number
• Duration: Call Duration
• Start Date Time: Date & Time of the call
There are a lot of other fields generated in the EDR depending on the
event type; Voice call, Video call, SMS, MMS, etc.

7. Main OSS / BSS Components
CRM
Contact Order Loyalty &
Call Center
Management Management Retention
Provisioning / Service Fulfillment
Service Network Workforce
Activation Inventory Management
Collection
Retail Billing System(s)
Switch
Data Bill
Mediation Rating Billing
Collection Production
SS7 Monitoring Interconnect Billing System(s)
Revenue Assurance
Test Call Generator Fraud Management

8. Data Collection
 Data Collection Design

9. Data Collection (Cont.)
 Exchanges Types
• Alcatel OCB, HC3.1, HC3.2, HC3.4
• Siemens EWSD
• Lucent 5ESS
• Ericsson AXE, AXD
• Nortel DMS
• Huawei UNO, CDMA, C&C08
• ZTE UNO, CDMA

10. Data Collection (Cont.)
 Billing Files Types
 AMA (Automatic Message Accounting)
• Contain the detailed events information
(EDRs)
 METER
• Contain the subscriber number and his
counters (pulsing)
• Obsolete

11. Data Collection (Cont.)
 Front Collector (FC) Function
 Interact with the exchange by its network protocol
(X.25, Ethernet, etc)
 Polling data files
 Data files storage
 The process is not just file coping, it is a self
managed process,
Automated scheduling of collection, automated
failure recovery, etc

12. Data Collection (Cont.)
 Central Access Network Server (CANS)
 Polling Files from FCs
 Transferring Files to Mediation
 Billing Files Storage

13. Mediation

14. Mediation (Cont.)
 What is Mediation ?
 Set of pre processing functions that are
applied to EDRs and other billing related
records.
 Provide the mediated data to the end systems:
• Retail Billing
• Interconnect Billing
• Revenue Assurance & Fraud Management
• Data Warehouse

15. Mediation (Cont.)
 Main Mediation Functions
 Collection and Archive
From Data Collections or from the switches
(in another setup)
 Parsing
 Applying The Business Rules

16. Mediation (Cont.)
 Parsing / Reformatting
 The process of decoding the input files
and transforming it to the required
format by the end system
 The Input files formats:
 ASCII (Delimited, Fixed Size)
 Binary (Fixed block size / variable block
size)

17. Mediation (Cont.)
Applying The Business Rules
 Normalization
• e.g.: Numbers Format, Time Format
 Filtration
• e.g.: Zero call durations, Non billing CRDs
 Correlation & Aggregation
• e.g.: OVERFLOW calls, Long call duration
 Duplicate Detection
 Data Enrichment

18. Mediation (Cont.)
Auditing & Reporting
 Reporting
• e.g.: Number of CDRs in specific switch per
day, month, etc.
 Error Processing
• Errors reporting & reprocessing.

19. Billing
 Retail Billing (“Billing” only)
• For postpaid subscribers
 Interconnect Billing (Wholesale
Billing)
• For other network operators

20. Retail Billing
 Rating
• Rate each EDR with the corresponding rate
 Billing
• Calculate the fixed charges, discounts, etc
(Bill Cycle)
 Bill Production
• Produce and print the invoices
 Collection & Payment
• Can be a part of billing system or a dedicated
system

21. Retail Billing (Cont.)
The rate Depend On :
• Service Type (Voice, SMS, MMS, etc)
• Destination (Local, Mobile,
International, etc)
• Time of the call (Peak, Off Peak)
• Subscriber's rate plan

22. Interconnect Billing
 Interconnection Terminology
Franchise 2
Franchise 1
 
Point of interconnect
Network
Address
InterconnecT
Owner 
Node
Network
Organisation Path
Operator (NOP)
Group

23. Interconnect Billing (Cont.)
 Interconnection Scenario
Invoice Direction ‘From’
Interconnect NOP
Owner
Call Direction ‘To’
 
Payment Direction
Invoice is based on the NOP’s charge for terminating a call

24. Interconnect Billing (Cont.)
 Call Types
Incoming (Interconnect)

Operator A Interconnect
Owner

Transit (Interconnect)
Retail

Operator B

Outgoing (Retail & Interconnect)

25. Interconnect Billing (Cont.)
 Interconnect Process
Call Detail
Records Network Operator
Outgoing Negotiations Invoice
Statement
Pricing Summary Reconciliation Settlement
Incoming
Statement Negotiations Invoice
Payment
Network Operator

26. Interconnect Billing (Cont.)
 Call Scenarios
• Direct Incoming / Outgoing
• Indirect Incoming / Outgoing
• Traditional Transit
• Reverse Incoming / Outgoing (Free Phone)
• Refile / Hubbing

27. Interconnect Billing (Cont.)
 International Agreements
• The international interconnection agreements differ than
the national interconnection agreements in many
aspects. e.g.
• National: Invoices
• International: Declaration

28. Optimized Routing
• A system which dynamically update the
routing table on the switch to select the best
route to every destination.
• The best route can be determined based on
the price, line quality, interconnect agreement
conditions, etc.
• The Optimized Routing system gets feeds
from interconnect billing and SS7 monitoring
to select the best route and update switches.

29. SS7 Monitoring
 SS7 Protocol
• Signaling protocol between network
elements (Switches)
 SS7 Monitoring Solutions
• Monitor the signals between switches
and generate reports / Build EDRs from
these information.

30. SS7 Monitoring (Cont.)
Probes
Switch A Switch B
SS7 Monitoring Solution

31. SS7 Monitoring (Cont.)
Signals for a call from Switch A to Switch B
Switch A Switch B
(1) IAM [called #]
(2) ACM
(3) ANM
(4) REL
(5) RLC

32. SS7 Monitoring (Cont.)
 SS7 Monitoring Importance
 For Network Analysis
Based on SS7 signals reports
• Identify network problems (e.g. Congestion)
• Identify Routing
• Control and increase the Quality of Service; QoS
• Planning future extendibility of the network

33. SS7 Monitoring (Cont.)
 SS7 Monitoring Importance
 For Revenue Assurance
Based on the EDRs built from SS7
signals
• Compare SS7 signaling EDRs with Switch
EDRs
• Identify possible fraud

34. Revenue Assurance
Revenue Assurance focus on detection
& correction of data discrepancies
between the operator‘s systems &
processes
RA get feeds from all systems and
apply a reconciliation to ensure that there
is no revenue loss in any system.

35. Revenue Assurance (Cont.)

36. Revenue Assurance (Cont.)
 Revenue Assurance Types:
1. Usage Assurance
• Reconcile the traffic (EDRs) between the systems;
Switches, Mediation and Billing.
• e.g. Compare the pre mediated EDRs (switches
EDRs) with post mediated EDRs (after mediation)
to ensure the mediation process.

37. Revenue Assurance (Cont.)
 Revenue Assurance Types:
2. Subscription Assurance
• Reconcile the subscribers’ profiles between the
switches and billing to avoid:
1. Under Billing: subscribers have the service but
not charged for it (exist in the switch but not
exist in the billing)
2. Over billing: an opposite of Under Billing

38. Revenue Assurance (Cont.)
 RA System Life Cycle
Files Measures
from all RA KPIs
Systems Transformation Database Reports
Dashboard
The transformation specification for each file called a Parser
Number of Parsers = Numbers of different input formats

39. Test Call Generator
• Can be considered under RA umbrella.
• Generate test calls to test any new service,
network element, route, etc.
• Generate calls using a pre configured
parameters; time, duration, destination, etc.
• Feed the RA with the log of generated calls and
RA reconcile it with switch EDRs to ensure the
correct charging.

40. Fraud Management
• Fraud management system focus on
detection any abnormal behavior
(pattern) within the network.
• Fraud management system apply
rules to detect any abnormal
behavior and fire alarms in a near
real time fashion.

41. Fraud Management (Cont.)
 Rules Examples
• If a subscriber makes 100 international
calls per day  Fire an alarm
• If a new subscriber makes GSM calls by
1000 EGP per day  Fire an alarm

42. Fraud Management (Cont.)
Examples of Fraud Types
1. Call Selling
a) The fraudster get a normal home phone.
b) Offers cheap rate international calls to public
c) Escapes away without paying the bills
• Pattern:
Huge international traffic for different countries from a
normal home user

43. Fraud Management (Cont.)
Examples of Fraud Types
2. Cloning
A. The fraudster clone a SIM card to another SIM
B. Fraudster make huge calls using the new SIM
C. The operator bills the original legitimate
subscriber for these calls and he refused to pay
• Pattern:
Two calls from the same numbers in the same time

44. Fulfillment / Provisioning
• Fulfillment / Provisioning is the automation
process for providing the services to the
customer.
• The process starting from the customer order
till activation the services on the network and
billing.

45. Provisioning (Cont.)
 The Old Manual Process
Customer Service Office
Shipping PBX
Work Switch
Order
Work Order
$
Copy
Shipping Billing System
Customer
TE CallCenter
Agent

46. Provisioning (Cont.)
 The Automated Process
CRM Provisioning Network
Channels: Sub Systems:
IVR Network Inventory
Web Site Service Activation
Call Center Workforce Management
Customer Point
Billing
eTopup Channels
Customer

47. Provisioning (Cont.)
• The provisioning process contain of multiple
subsystems organized by a process workflow.
• The Provisioning / fulfillment solution can be
implemented as a suite or separated systems
integrated together.
• The level of automation is dependent on the
implementation of the provisioning systems.

48. Provisioning (Cont.)
 Service Activation
• The system who activate the service on the network
element (Switches)
• Interact with the different network elements by different
languages & commands

49. Provisioning (Cont.)
 Network Inventory
• Holds all detailed information about the network
elements (switches, ports, cables, etc.)
• Using this information, the operator can
determine the best way for providing the service.
e.g. what is the shortest route to connect two
sites using the leased line.

50. Provisioning (Cont.)
 Workforce Management System
• Distribute the work orders automatically on the
labor for providing a service or solving a problem.
• Distribution can be based on location,
capabilities, tools availability, work load, etc.

51. Number Portability Management
• The Number Portability is the ability for
subscribers to change their service provider
(Telecom Operator) without changing their
phone numbers.
• e.g. Mobinil (012 1234567)  Vodafone (012
1234567)

52. Number Portability Management
 Number Portability Management
Systems
• NPC: Number Portability Clearinghouse
• NPG: Number Portability Gateway

53. Number Portability Management
 Number Portability Clearinghouse (NPC)
• Centralized reference database for ported
numbers.
• Existing at the Regulator.
• Mange the portability process between the
Telecom Operators.

54. Number Portability Management
 Number Portability Gateway (NPG)
• The interface of Number Portability service at
each Telecom Operator.
• Mange the portability process between the
Telecom Operator & NPC.

55. Number Portability Management
 Call Routing Types
1. Indirect
Each call to a ported number
should go to the original operator
(Donor) and he forward it to the
Recipient operator.

56. Number Portability Management
 Call Routing Types
2. Direct
Each operator know where the
ported number be and forward the
call direct to his new network.

57. Finally, We Cover
 General Concepts
 Data Collection
 Mediation
 Billing
 SS7 Monitoring
 Revenue Assurance
 Fraud Management
 Fulfillment / Provisioning
 Number Portability Management

58. Thanks to all my colleagues who help me for preparing this
presentation.