Lessons Learned: Implementing VoLTE Roaming

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#VoLTELessons

Lessons Learned: Implementing VoLTE Roaming

Mary ClarkChief Marketing Officer, Syniverse @SyniverseCMO

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#VoLTELessons

Global VoLTE Deployments

Commercially launched VoLTE

Investing in VoLTE deployments

111 MNOs investing in

VoLTE - GSA

30 MNOs in 21 countries

with commercially

launched VoLTE voice service

- GSA

755 million LTE connections

worldwide - GSA

442 commercially launched LTE

networks - 147 countries

- GSA

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#VoLTELessons

VoLTE Market Forecast

83% of carriers surveyed say they will deploy VoLTE by 2016

- Infonetics

72M VoLTE roaming MOUs in 2015278M VoLTE roaming MOUs in 2016VoLTE roaming MOUs will grow by CAGR of 145% over next 5 years to

reach 4.7B by 2020- HOT TELECOM

600 million Smartphone users worldwide will use VoLTE by 2018 as their default voice

service - Analysys Mason

VoLTE connections forecast – Analysys Mason, 2015

Current state of VoLTE launches– Analysys Mason, 2015

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#VoLTELessons

Already Launched

Next 6 Months 6-12 Months

12 Months or Beyond Undecided

If you are planning to launch LTE/VoLTE on your home network, what is your timeline?

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#VoLTELessons

Haven’t Launched Home

Network YetNext 6 Months 6-12 Months

12 Months or Beyond Undecided

If you are planning to launch LTE/VoLTE roaming, what is your timeline?

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#VoLTELessons

Keith Dyer, Founder and Editor, The Mobile Network Founded The Mobile Network in 2013, introducing a new voice to the

media covering mobile network technology. 17 years experience covering the mobile network technology ecosystem

as a journalist and editor. Tracked the development of the VoLTE ecosystem since its beginnings.

John Wick, Senior Vice President and General Manager – Mobile Transaction Services, Syniverse Responsible for the management and growth of Syniverse’s IP, SS7 and

number portability product lines. Joined Syniverse in 1993 as a senior critical support analyst with the

network operations department. Certified Six Sigma Black Belt.

Today’s Expert Panelists

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#VoLTELessons

Keith Dyer

Founder and Editor, The Mobile Network@keithdyer

#VoLTELessons

VOLTE – operator experiences

05/03/2023 VoLTE I Operator Experiences and Learning 9

• Clear commitment to the service• But it’s not been

easy…

#VoLTELessons



• Optimisation and tuning of radio network

• New characterisation and visibility for quality assurance

• Extensive and complex testing • Intensive efforts in IMS• Integration Billing and BSS• Device support• Consumer education

“This is the most complex thing I’ve ever worked on in 20 years.”

#VoLTELessons



“Our customers love it…”

Customer benefits• Set-up time

SK Telecom customer survey

• Call quality• Battery upside• Service richness?

#VoLTELessons



Do operators love it more?

• Long term spectrum turn-off• More efficient use existing spectrum

• Signalling efficiency of all IP• Potential for new (IMS) services

• Supporting infrastructure enables VoWifi

#VoLTELessons



Limited VoLTE roaming to date… why?

• LG UPlus & KDDI• LG UPlus & Smartone• NTT and KT

Credit: Ovum Whitepaper, Feb 2015

#VoLTELessons



Well, why enable VoLTE roaming anyway?• Customer access to high quality

voice and video calls• Keep customers on-brand

• Ensure quality for high value customers• Long term – 2/3G switch off in home/visited

networks• Fate – it’s going to happen anyway

#VoLTELessons



The technical hurdles

• RAVEL - complexity• S8HR – lacks feature

supportFix it at home first…

India Times – December 2015

#VoLTELessons



CONCLUSIONS AND QUESTIONS

• How should we do it?

Real commitments, it will happen but operators are asking…

• When should we deploy?

#VoLTELessons

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#VoLTELessons

John Wick

Senior Vice President and General Manager Mobile Transaction Services, Syniverse

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#VoLTELessons

VoLTE Interconnect vs. VoLTE Roaming

IPX

MNO A MNO B

VoLTE Interconnect

IPX

MNO A MNO B

VoLTE Roaming

MNO A Subscriber@ Home

MNO B Subscriber@ Home

MNO A SubscriberRoaming

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#VoLTELessons

Challenges Lawful intercept/Emergency calling

Lawful intercept – allows home network, but not at visited network location

Emergency calling Voice Call Continuity (moving from VoLTE to CS)

No service visibility for VPMN Distinguishing data traffic from VoLTE by APN and QCI

only SMS not distinguishable from signaling

Cannot retail bill based on TAP

VoLTE Roaming Scenarios Home-Based Routing (S8HR)

Advantages Faster to deploy than LBO – Uses same GTP

tunnel as LTE Data Roaming traffic Utilizes the same components already in evolved

packet core (VPMN does not require IMS Core) Can use same data IOT charges with roaming

partners, no need to update roaming agreements for IMS services

Uses existing TAP and RAEX with only minor changes

IPX

IPX

E-UTRAN

MME

VPMN A-Party HPMN A-Party

B-Party

HSS

P-CSCF

S-CSCF

TAS

SGW

DRA

IBCF

VoLTERoaming

Interconnect

IMS

IMS eXchange

PCRF

PGW

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#VoLTELessons

VoLTE Roaming Scenarios Local Breakout

Advantages Session awareness at the served network Visibility into the control and media plane of a

call or video session taking place Gives ability to offer lawful intercept and

emergency call handling Continuity of a voice call between LTE and CS Support for billing model - TAP for retail billing

Challenges Complexity (flexibility and power, but more complex) IMS interoperability challenges with LBO – different

vendors/different implementation Requires multiple feeds from many network elements for

both VPMN and HPMN LBO for VoLTE with S8HR for data adds complexity New TAP record types (mobile session/messaging event) that

are unused today

IPX

IPX

xCSCF

MME

VPMN A-Party HPMN A-Party

B-Party

HSS

P-CSCF

S-CSCF

TAS

IBCF

DRA

IBCF

VoLTERoaming

VoLTE Interconnect

EPC

IMS

IMS

IMS eXchange

IMS eXchange

PCRF

IBCF

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#VoLTELessons

First Transoceanic VoLTE Roaming• Collaboration with an American and Japanese operator to enable the world’s

first transoceanic VoLTE roaming call based on an S8HR architecture

Established VoLTE roaming between South Korea and Japan• LG Uplus subscribers from Korea roaming onto the KDDI network in Japan

Launch of the world’s first commercial VoLTE roaming service• LG Uplus subscribers from Korea roaming onto the SmarTone network in Hong

Kong

Lessons Learned:VoLTE Roaming Trials and Implementation

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#VoLTELessons

Connection setup and call quality are better than 3G Real time control of voice traffic - eliminates need

for CAMEL, helps control fraud Handsets do not default to VoLTE for roaming

Operators must work with handset vendors to modify defaults

Assumed that the home operator would support lawful intercept. Not valid in all cases due to regulations within

countries. Charging for VoLTE needs to be worked out by each

operator. Example: Some operators charge LTE data IOT rates for

VoLTE. If operators prefer a different IOT they must distinguish VoLTE from LTE data using APNs/QCIs.

Lessons Learned – S8HR

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#VoLTELessons

Operators must understand how their roaming partner(s) supports S8HR How QCIs are configured Maximum bit rate for each QCI Number of APNs and which APNs are supported per QCI

Video calls started during voice calls difficult to distinguish by VPMN Appears as another data flow so two separate TAP records

are created HPMN needs to consider correlation of records for retail

billing SMS is viewed as signaling

If signaling is not charged between roaming partners SMS is no charge

May open the door for messaging SPAM GSMA recommends charging for signaling to alleviate

potential issues

Lessons Learned – S8HR

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#VoLTELessons

Q&A

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#VoLTELessons

Thank You!

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