Transcript Omnitele Presentation - CANTO | Caribbean Focus, Global

UMTS Quality of Service
enabling new mobile applications
CANTO
St. Kitts & Nevis, 19th – 22nd June 2005
Heidi Lagerström, [email protected]
© Omnitele Ltd. 2005
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Agenda
1. Introduction to UMTS
• New services
2. Quality of Service (QoS) in UMTS network
• Using QoS to improve service quality
3. Service quality measurements in UMTS network
• Different ways to measure service quality
• Defining correct Key Performance Indicators (KPIs)
4. Conclusions
© Omnitele Ltd. 2005
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New generation of mobile networks
UMTS
• New data services are driving up traffic in mobile
networks
• ARPU generated by data users is rising
• Rise in traffic will bring challenges in maintaining
acceptable quality of service
• Service quality is closely tired to new service acceptance
Data Rates
2000
Need to build more
network capacity!
Maximum Data Rate (kbps)
1800
1600
1400
1200
1000
800
600
400
200
0
GSM
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GPRS
EDGE
UMTS
Introducing new services
Improved performance, decreasing cost of delivery
3G-specific services take
advantage of higher bandwidth
and real-time QoS
Broadband
in wide
area
Video sharing
Video telephony
Real-time IP
Multimedia and games
A number of mobile
services are bearer
independent in nature
WEB browsing
Corporate data access
Streaming audio/video
Voice &
SMS
GSM
MMS picture/video
xHTML browsing
Application downloading
E-mail
Presence/location
GPRS
EDGE
Higher bit rates
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UMTS
HSDPA
Agenda
1. Introduction to UMTS
• New services
2. Quality of Service (QoS) in UMTS network
• Using QoS to improve service quality
3. Service quality measurements in UMTS network
• Different ways to measure service quality
• Defining correct Key Performance Indicators (KPIs)
4. Conclusions
© Omnitele Ltd. 2005
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Why do we need QoS?
•
•
•
•
UMTS networks support services with very different performance
requirements
– Real-time services require performance guarantees
– Customer acceptance closely tied to service quality
Optimal usage of network resources
– Radio resources scarce
– Cost-effectiveness
– Return of investment
Service and user differentiation
– Meet different needs of customers
(e.g. business vs. consumer)
Performance Requirements
– Support different services
Sensitivity
Application
Bandwidth
(real-time vs. best effort)
Delay
Jitter
Video call
High
High
High
Competitive advantage!
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Loss
Med
Streaming
High
Med
Med
Med
Web browsing
Med
Med
Low
High
E-mail
Low
Low
Low
High
QoS Traffic Classes
Traffic class
Characteristics
Example
application
Conversational
Preserve time relation between
information entities of the stream.
Conversational pattern (stringent
and low delay)
Speech
Video calls
Streaming
Preserve time relation between
information entities of the stream.
Real-time
streaming
video
Interactive
Request-response pattern.
Preserve payload content.
Web
browsing
Tolerant
• Delay and bit rate
can vary
• Integrity
Background
Destination is not expecting the
data within a certain time.
Preserve payload content.
E-mail
File
downloading
Easiest
• Delay and bit rate
can vary
• Integrity
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Demanding
• Delay
• Jitter
Demanding
• Bit rate
• Jitter
QoS Profile Attributes
R99 QoS attribute
Example value
Residual BER
10 –5
SDU error ratio
10 –4
Delivery of erraneous SDUs
No
Maximum SDU size (octets)
1500
Delivery order
No
Transfer delay
100 ms (conversational)
280 ms (streaming)
ARP
1, 2 or 3
Traffic Class
Conversational,
streaming, interactive,
background
Depends on
operator’s
QoS strategy
THP
1, 2 or 3 (same as ARP)
Maximum allowed bit rate
e.g. 64, 128 or 384 kbps
Maximum guaranteed bit rate
e.g. 64, 128 or 384 kbps
Depends on
the QoS strategy
and UE/RNC
capabilities
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QoS Differentiation
Video
telephony
Streaming
Conversational RAB
Streaming RAB
Push-to-talk
Interactive RAB, THP/ARP = 1
Interactive RAB, THP/ARP = 3
Web
browsing
Background RAB
MMS
• Each service gets the treatment it requires according to the QoS profile
• Network resources are shared according to the service needs
• Network resources can be used more efficiently
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Operators’ QoS Strategy
Application
server
Node B
RNC
Conversational RAB
Streaming RAB
Interactive RAB, THP/ARP = 1
Interactive RAB, THP/ARP = 3
Background RAB
• Operators can practise user differentiation by
giving each user set of QoS profiles, which
he/she is entitled to use
• Operators can practise service differentiation
by mapping each service to the bearer that
meets its requirements
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3G
GGSN
3G
SGSN
HLR
User profiles are stored in HLR.
Each user can have several user
profiles, which correspond to
different services and are mapped
to different bearers according to the
operator’s strategy.
• Meet the needs of different
customers
• Offer each service the quality
it requires
• Optimise network resource
usage
Agenda
1. Introduction to UMTS
• New services
2. Quality of Service (QoS) in UMTS network
• Using QoS to improve service quality
3. Service quality measurements in UMTS network
• Different ways to measure service quality
• Defining correct Key Performance Indicators (KPIs)
4. Conclusions
© Omnitele Ltd. 2005
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Measuring network performance
Customer
feedback
Network Performance Monitoring
 Optimisation
Network statistics from different counters and interfaces
E2E
service
quality,
QoE
Application
server
Node B
RNC
UTRAN
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Performance
statistics from
application server
3G
GGSN
3G
SGSN
Core nw
External nw
End-to-end field measurements
Hot spot tests
Drive tests
• Coverage
• Service availability
• Mobility
• Service performance
• Indoor coverage
• Congested places
(e.g. railway stations, shopping malls)
Walk tests
Benchmarking
• Service availability
(e.g. city center)
• Mobility (low speed)
• Comparative data
• Competitor evaluation
Node B
RNC
UTRAN
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3G
SGSN
3G
GGSN
Core nw
Application
server
External nw
Defining the right KPIs
•
Different services have different quality requirements
– KPIs must be defined separately for each of the key services
•
KPI categories
– Service Accessibility
– Service Integrity
– Service Retainability
•
With inadequate performance indicators and monitoring
– Hidden problems in network performance and user perceived
quality of service
– Poorly defined indicators may show better quality than in the reality
• Incorrect formulas and counters
• Unreasonable measurement periods
(too much averaging etc.)
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Example: Voice Services - CS
Customer
demand
Indicator
Measure
Service
accessability
Availability & Coverage
Blocked calls
Call setup delay
Ec/No, RSCP
Admission control
RAB assignment
Service integrity Voice quality
Noisy frames (FER),
MOS
Service
retainability
Handover failure
No coverage
Interference
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Dropped calls
Example: Data Services - PS
Customer demand
Indicators
Measures
Service
accessability
Availability & Coverage
Blocked service access
Service access delay
Ec/No, RSCP
Admission control
Attach, PDP context
activation, IP service setup
Service integrity
Video quality
Audio quality
Web page download time
E-mail sending time, etc.
BLER, FER, throughput,
delay, jitter
Service
retainability
Dropped data connection
Connection timeouts
Dropped PDP context/attach
No coverage
Handover failure
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WCDMA vs GSM field measurements
GSM
• BCCH carrier
• TCH
• PDCH
• RXLev
• C/I on BCCH
• RXQual/ BER
• MS TX power
• HO success
• Throughput (GPRS)
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WCDMA
CPICH
DCH
DCH, Common RACH/FACH
RSCP
CPICH Ec/No
DCH BLER
UE TX power
SHO/HHO division, ISHO
IFHO success, CM usage
Throughput per RAB
Example: CPICH coverage – Ec/No
Operator 1
According to Ec/No values
both operators have good
coverage. Couple of RED
areas, which need to be
further investigated!
Operator 2
If large interference areas are
generated, the problem could be
minimised later by adjusting the
antenna direction or height, or by
down tilting the antenna or by
slightly tuning the pilot power
levels.
© Omnitele Ltd. 2005
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Agenda
1. Introduction to UMTS
• New services
2. Quality of Service (QoS) in UMTS network
• Using QoS to improve service quality
3. Service quality measurements in UMTS network
• Different ways to measure service quality
• Defining correct Key Performance Indicators (KPIs)
4. Conclusions
© Omnitele Ltd. 2005
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Conclusions
• UMTS networks bring more capacity to GSM/GPRS mobile
networks
– Enables operators to launch new services
– Increases the ARPU generated by subscribers
– Offers better service quality
• In 3G networks QoS management is required
– Real-time services require QoS guarantees
– Need to support different kinds of services
– With QoS mechanisms operators can use their network resources
more efficiently and gain competitive advantage
• To maintain and improve the network performance and user
experienced service quality constant monitoring and performance
follow-up is needed
– Successful network measurements are based on correct KPI
definitions
– A combination of end-to-end field measurements, interface probes,
network element counter statistics and customer feedback is required
© Omnitele Ltd. 2005
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For more information about Omnitele,
please visit our web site
www.omnitele.fi
2004
© Omnitele Ltd. 2005
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How can Omnitele help you?
• Network acceptance testing
• Network parameter planning
• Network audits for GSM/GPRS/EDGE and UMTS
networks
–
–
–
–
KPI analysis
Drive tests
Hot spot tests
Benchmarks
• Network counter analysis
• Network optimisation
© Omnitele Ltd. 2005
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