Workshop on “Monitoring and Benchmarking of Quality of
Service and Quality of Experience of Multimedia Services in Mobile
Networks”
(Buenos Aires, Argentina, 24-25 July 2014)
Quality of Service Measurements of Mobile
Networks
Yvonne UMUTONI
Quality of Service Development Group (QSDG) Chairperson
yvonne.umutoni@rura.rw
+250 782052394
EXECUTIVE SUMMARY
This presentation focuses on the quality of service
monitoring and enforcement for mobile networks from
the Regulatory point of view.
It covers the following:
purposes of QoS regulations
Requirements for a Regulator in order to enforce Quality of
service
Purpose of Auditing the QoS and auditing methods
prerequisites so as to conduct a QoS Measurement Campaign
QoS Parameters of some mobile services such as voice, sms,
data…
Buenos Aires, Argentina, 24-25 July 2014
QUALITY OF SERVICE REGULATION
QoS is defined as the “Collective effect of service
performance, which determines the degree of satisfaction
of a user of the service” [ITU-T Recommendation E.800].
QoS regulation is part of customer protection;
But customer protection is broader than QoS regulation and
QoS is not the same as network performance, which is more
concerned with standards for the network, not user experience.
Buenos Aires, Argentina, 24-25 July 2014
QUALITY OF SERVICE REGULATION
(Cont…)
Main purposes of QoS regulation are [ITU-T Supp. 9 of
E.800 Series]:
Helping customers be aware of the Quality of service provided
by Telecom Operators/ ISPs through networks (mobile & fixed),
so that to make their own choices;
Checking claims by operators;
Understanding the state of the market;
Maintaining / improving the QoS in presence of competition;
Maintaining / improving the QoS in absence of competition;
Helping operators to achieve fair competition; and
Making interconnected networks work well together.
Buenos Aires, Argentina, 24-25 July 2014
ENFORCEMENT OF QUALITY OF SERVICE

Requirements so as to enforce the quality of service:
i.
ICT Law:
Adopted and published in the Official Gazette
ii.
Regulations / Guidelines of Quality of Service in
Mobile networks:
•
With a purpose:
•
•
•
•
•
Improve / maintain service quality;
make QoS Information available to customers;
assist the development of telecommunication markets and;
improve operation and performance of interconnected networks.
Guidance about:
•
•
Methodologies for measuring, reporting and recording.
QoS parameters definitions and thresholds.
Buenos Aires, Argentina, 24-25 July 2014
ENFORCEMENT OF QUALITY OF SERVICE
(Cont..)
iii.
Reports of QoS submitted Monthly or Quarterly by
Telecom Operators to the Regulatory Authority:
Include technical and non technical parameters
iv.
QoS Monitoring Tools for auditing the QoS of
mobile networks independently
v.
Staff in charge well trained
Buenos Aires, Argentina, 24-25 July 2014
AUDIT OF QUALITY OF SERVICE
Purpose of QoS Auditing :
Verify the QoS of Mobile Networks experienced by customers
and
Compare the Results (from audit exercise) against the licence
obligations
Methods to audit telecom operators’ mobile networks are,
but not limited to:
Drive Test (performed on quarterly basis or any time required)
Consumer survey
Data submitted on monthly or quarterly basis by Mobile
Telecom Operators
Etc.
Buenos Aires, Argentina, 24-25 July 2014
METHODOLOGIES FOR MEASUREMENT
This presentation focuses on Drive Test Methodology
QoS Measurement Campaign prerequisites:
Specify Locations (e.g.: City, sector)
Prepare maps for those locations
Calculate Samples (attempts) required for each location
based on population: For more information, please refer to
ITU-T Recommendation E.804.
Calculate number of days/ hours required
Calculate number of hotspots (for measurement of data
services) and locate those hotspots
Prepare a script for each service (e.g: Voice, FTP, HTTP…)
For Voice service measurement, specify the Mode (e.g:
GSM, 3G or Dual mode)
Buenos Aires, Argentina, 24-25 July 2014
METHODOLOGIES FOR MEASUREMENT
(Cont...)
Example of Voice call sequence:
Start loop
Make a voice call from MOC to MTC
Call duration: wait 90, or 120 seconds
MOC disconnects the call (Hang-up)
Pause (Idle Mode) time: wait 20 seconds
End loop (go back to step 2)
Buenos Aires, Argentina, 24-25 July 2014
QUALITY OF SERVICE PARAMETERS
VOICE KPIs
Definitions
Call Setup Success Rate
(CSSR)
CSSR denotes the probability that the end-user can access
the mobile telephony service when requested if it is
offered by display of the network indicator on the user
equipment
Call Setup time (CST)
CST describes the time period between sending of
complete address information by the MOC and receipt of
call set-up notification or an alerting message.
Call Drop Rate (CDR)
CDR denotes the probability that a successful established
attempt is ended unintentionally by MOC or MTC party
Speech Quality
Speech quality on sample basis: is an indicator
representing the quantification of the end-to-end speech
transmission quality of the mobile telephony service.
Service coverage Area
(Signal level): ≥ -95
dBm.
The Service coverage area verification depends on
Operator’s coverage plan.
Buenos Aires, Argentina, 24-25 July 2014
QUALITY OF SERVICE PARAMETERS
(Cont…)
KPIs for SMS
Definitions
SMS Service
Accessibility
SMS service accessibility denotes the probability that the enduser can access the SMS when requested while it is offered by
display of the network indicator on the user equipment.
SMS Completion
Ratio
SMS Completion Ratio is the ratio of successfully received and
sent messages from the sending UE (user equipment) to the
receiving UE, excluding duplicate received and corrupted
messages.
SMS End-to-End
Delivery Time [s]
SMS end-to-end delivery time is the time period between
sending a short message to the network and receiving the very
same short message at another UE.
Buenos Aires, Argentina, 24-25 July 2014
QUALITY OF SERVICE PARAMETERS
(Cont…)
KPIs Data services
Definitions
Attach failure ratio
Attach failure ratio denotes the probability that a subscriber
cannot attach to the Packet Switched (PS) network.
Attach Setup time
Attach setup time describes the time period needed to attach to
the PS network
PDP Context Activation
Failure Ratio
PDP context activation failure ratio denotes the probability
that the PDP context cannot be activated. It is the proportion
of unsuccessful PDP context activation attempts and the total
number of PDP context activation attempts.
PDP Context Activation
Time
PDP context activation time describes the time period needed
for activating the PDP context.
PDP Context Cut-off Ratio
PDP context cut-off ratio denotes the probability that a PDP
context is deactivated without being initiated.
Buenos Aires, Argentina, 24-25 July 2014
PUBLICATION
For Consumer protection and Awareness purposes, the
Quality of Service results from Audit Campaign (drive
test, consumer survey...) are published by Regulators,
on website, or in magazine for a regulator;
Buenos Aires, Argentina, 24-25 July 2014
Thank you for your attention
Buenos Aires, Argentina, 24-25 July 2014