Network Breaking Point

Network Breaking Point:Network Breaking Point: Managing demand and user

experienceHugh Bradlow

Chief Technology OfficerChief Technology Officer

Telstra Corporation Ltd

© 2011 Telstra Corporation Limited. All rights reserved

OverviewDrivers of Demand

Designing Networks for user experienceDesigning Networks for user experience

Meeting demand without breaking the network

h l– New Technology

– New Spectral Bands

– Traffic Management

– Femtocells

© 2011 Telstra Corporation Limited. All rights reserved 3

The 2 dimensions of network demandRelative RAN Signalling Load per MByte of Data

Traffic Demand Global mobile data traffic grew 2.6-fold in 2010.

100

Expecting 26-fold increase between 2010 and 2015. (Cisco, 2011)

M2M (sensor,P lli @ 20 )

Smart phone

10Polling @ 20 sec)

TabletFeature phone

1

User Data (per device)MByte/Month (2010)

Feature phone Laptop

1 10 1000100

Traffic Capacity and Signalling Capacity are both potential bottlenecks© 2011 Telstra Corporation Limited. All rights reserved 4

Designing for User Experience

“Al 3G”

World Class Network Availability

• “Always 3G”

• With extensive coverage

• Backhaul capacity

• Signal Strength for indoor Weekly Record

g gcoverage

• Technology Leadership

Superior Downlink Throughput

Technology Leadership

• Continuous Monitoring

5

Weekly Record

© 2011 Telstra Corporation Limited. All rights reserved

Technology advances improve spectral efficiency2 02.0

2007 2009 HSPA+ P f h i2007 2009 HSPA+ P f h i

2015 LTE-Adv – Further performance enhancing technologies for LTE – advanced

2015 LTE-Adv – Further performance enhancing technologies for LTE – advanced

1.5

/M

Hz 2004 WCDMA – CDMA with increased

bandwidth (5 MHz)2004 WCDMA – CDMA with increased

bandwidth (5 MHz)

2007 – 2009 HSPA+ – Performance enhancing technologies added to HSPA (64QAM, MIMO, dual

channel). Also, importantly, improved handset

2007 – 2009 HSPA+ – Performance enhancing technologies added to HSPA (64QAM, MIMO, dual

channel). Also, importantly, improved handset 2011 LTE – OFDM –reduced

interference, frequency domain 2011 LTE – OFDM –reduced

interference, frequency domain

MIMO, carrier aggregation, heterogeneous networks, relays, cooperative

communications

MIMO, carrier aggregation, heterogeneous networks, relays, cooperative

communications

1.0

s/ce

ll/ 2003 EGPRS – TDMA optimised for packet

data. Enhanced with 8PSK, HARQ2003 EGPRS – TDMA optimised for packet

data. Enhanced with 8PSK, HARQ2006 HSPA – CDMA optimised for packet data2006 HSPA – CDMA optimised for packet datareceivers (two antennas, equaliser)receivers (two antennas, equaliser)scheduling, improved MIMO, scalable bandwidth up to 20 MHz

(& others)

scheduling, improved MIMO, scalable bandwidth up to 20 MHz

(& others)

communicationscommunications

0.5Mb

ps 1992 GSM – Basic TDMA – no

smarts2001 GSM – Improved interference control

using Slow Frequency Hoppint2001 GSM – Improved interference control

using Slow Frequency Hoppint

(& others)(& others)

0 0

6© 2011 Telstra Corporation Limited. All rights reserved

0.0

1990 1995 2000 2005 2010 2015

Technology advances also reduce cost per bit

Cost per MByte as % of GPRS

80

90

100

40

50

60

70

10

20

30

40

0

GPRS EDGE WCDMA

(R99)

HSDPA HSPA+ LTE


LTE performance improvements

DL Spectral efficiency Target

p pOpens up new frequency bands

– Flexible allocation of radio channel bandwidths between 1.25 MHz and 20 MHz utilising FDD and/or TDD duplex modes

Possible

R10 HSPA+ ?

Spectral efficiency

3

4

Sect

or HSPA+LTE (10 MHz)

MHz and 20 MHz, utilising FDD and/or TDD duplex modes

Enhanced Radio Network performance:

– Increased spectral efficiency

0

1

2

Bits

/Hz/

S ( )

R7 R8 R8 R8 R9 R9 R10

– Lower Latency

– Peak data rates:

• Downlink >100 Mbps (> 40 Mbps cell average) 0p ( p g )

• Uplink >50 Mbps

Also enhanced core networkRTTLatency

– Flat All‐IP network architecture

– Self‐organisation, self‐configuration and self‐optimisation

~‐20 ms

~‐80 ms


Data Demand outstripping Technology Improvement60

40

50

60

Spectral efficiency8 value

10

20

30Spectral efficiency improvements

Data demand growth

times 2008

Spectral efficiency improvements and data demand growth relative to 2008

0

2006 2008 2010 2012 2014 2016

X

Further technology improvements

Technology Improvements not keeping pace with demand

Limited Spectrum resources for mobile access services (450MHz to 3.4GHz)

What else is possible?

– Open up New spectral bands

l d l• Including using TDD to utilise more spectrum

– Traffic Management


New Spectral Bands10 MHz centre gap5 MHz 3 MHz

45 MHz 45 MHz698 MHz 806 MHz694 MHzPPDR/LMRDTTV

700 MHz DD band:

PossibleFDD FDD??

15 15 15 15 15 15Possible Channels:

15 MHz

15 MHz

15 MHz

15 MHz

15 MHz

15 MHz

1800 MHz band:

75 MHz Fixed & MobileServices

Met Satellite

20 MHz centre gap

75 MHz

1710 MHz

1800 MHz band:1880 MHz

Possible Channels:

Various combinations of 10/15/20 MHz channels

FDD FDDTDD?

10+10?Various combinations of 10/15/20 MHz

channels

2500 MHz

2500 MHz band:

70 MHz 70 MHz

2690 MHz

Earth Exploration & Radio Astronomy

Satellite (various) 50 MHz centre gap

FDD FDDTDD

Possible Channels:

20 MHz

20 MHz

20 MHz

10 MHz

20 MHz

20 MHz

20 MHz

10 MHz

10 MHz

10 MHz

10 MHz

10 MHz

10 MHz

2300 MH b d

98 MHz Class Licenced – LIPDs/Wi‐FiSpace Research


2300 MHz band:2302 MHz 2400 MHz

Possible Channels:

20 MHz

TDD

20 MHz

20 MHz

20 MHz

10 MHz

4 MHz

4 MHz

Traffic Management Application

3GPP Rx (Di t )

NSN PCS 5000(3GPP PCRF)

Telstra

NSN OneNDS(3GPP SPR)

(Diameter) or SOAP

Traffic Management Telstra

services3GPP Gx(Diameter)

Policy ControlAcceleration Ericsson GGSN Internet

PCRF – Policy & Charging Rules FunctionSPR – Subscription Profile Repository

Policy Control

QoS

Acceleration

Charging SPR Subscription Profile RepositoryQoSmechanisms

Charging mechanisms

Application based priority

Terminal based priority

Location based priority

User based priority

ConnectionScheduling Priority Active Rate shaping


Connection Admission Control

Scheduling Priority Active Queue Management

Rate shaping

“Why QoS?”: Meeting performance targets100

sec)

Real-time Service without QoS ProtectionReal-time Service with QoS Protection

1

10

sfer

Del

ay (s Non-real-time service at best-effort QoS

Acceptable User Satisfactionfor Real-time Service

0.1

1

Bur

st T

rans

100ms

0.01

0 0.2 0.4 0.6 0.8 1Avg

. Pkt

.

Utilisation ρ

Without QoS, the traffic exceeds performance targets at relatively low network utilisation (~45%)

With QoS, the network is capable of high utilisation (up to 95%) while still meeting the performance targets for the real‐time traffic

Utilisation, ρ

– Connection Admission Control (CAC) is required for the real‐time traffic to prevent overall network collapse.


Network Build Options for Public Safety Agencies

InternetSeparate Network1 Internet

Public IP Core

p

PSA IP Core

Public 3G/4GAccess Network

Network

Public UEs

Public Packet

Gateway

PSA IP Core Network PSA

Packet Gateway PSA

3G/4G AccessNetwork

Public Safety Agency (PSA) Command Centre

Public UEs

Shared Network but not Complete Sharing

Network

2 3Shared Network but notSpectrum QoS-enabled

Packet Gateway

CommonIP Core

Complete Sharing

InternetInternetCommon IP Core

2 3

IP Core Network

Fully Shared3G/4G AccessPartially Shared

3G/4G Access

IP Core NetworkCommon

Packet Gateway

Network (towers + spectrum) PSA Command

Centre

3G/4G AccessNetwork (towers only) PSA Command

Centre


Signalling and Acceleration

CELL_DCH

CELL_FACH_

CELL_PCHor

URA PCHURA_PCH

IDLE


IDLE

FemtocellsUser‐installed – Why bother?

– Coverage? Next GTM: Indoor coverage already excellentCoverage? Next G : Indoor coverage already excellent

– Capacity? Data hungry devices already offload to Wi‐Fi (laptops, tablets)

Operator‐installed – Network cost reduction

– As part of a planned network, femto and pico‐cells can reduce network costs


Summary

Demand for Wireless Broadband is exceeding improvements in Spectral Efficiency

New Spectral Bands are part of the solutionsolution

Traffic Management will be critical in meeting demand


Documents

Network Breaking Point