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SAP Mobile Services

IPX Snapshot: Interconnecting Services and Enabling Global Roaming

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© 2015 SAP SE or an SAP affiliate company. All rights reserved.

Table of Contents3 A Brief History of Roaming and Interconnect

5 The IPX: The Time Is Now

9 A Brave New All-IP World

11 Making the Right Connections

16 Nine Ways to Get More Value out of IPX

18 Expanding Voice Connectivity over IPX: An Operator Perspective

21 Best Practices for LTE Roaming

25 Boosting Trust, Building Business

28 VoLTE and RCS: Network Evolution and Services Revolution

31 The Wide, Wide World of the IPX

34 Glossary

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A Brief History of Roaming and Interconnect

In our annual mobile operator guide, we capture the thoughts of operators and industry groups on networks and roaming. Three years ago the contributors to the guide expected “an open and flexible model for service exchange to be part of the critical path the industry would travel in order to implement voice over Internet Protocol (VoIP).” They also indicated they expected VoIP services to drive the move to an all-IP environment that would stimulate the use of IPX. “IPX is a given,” operators said earlier. “For customers, it’s all about being able to experience the same quality overseas that they have come to expect in their home network.” Some predicted, “Moving forward, IPX will offer a flatter IP network archi-tecture, enabling voice-over-LTE services.”

Since then the industry has grown from roughly 90 LTE networks in 2012 to 500 networks in 2015. There are now more than 20 IPX providers, hailing from two general groups. One set of pro-viders offers data roaming services over GRX, and the other is composed of traditional voice and signaling interconnect players.

The role of IPX is changing and expanding. As originally defined, it is clear that IPX was never meant just for mobile operators. It is easy to envi-sion the security provided by this connectivity becoming attractive and relevant to enterprise businesses. It might also be used to host more services and applications than we can imagine now.

The GSMA developed IPX for operators to enable their subscribers to roam globally and to interconnect its full suite of voice and data services through a secure IPX connection. It defined standards to enable interoperability from technical and commercial perspectives. But over the last few years, IPX moved from just a network to enable roaming to a hub for enabling services and applications beyond traditional voice and data. IPX enables three key aspects for an operator: a seamless roaming experience, scale, and services. The question has changed from “What is IPX?” to “What all is enabled over IPX?”

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With four times the growth in LTE networks and hundreds of operators and service providers ready for LTE roaming, we can see most of these expectations and suggestions coming to life now. It is a good time to take a moment and reflect on how the industry has evolved. This guide brings together views of operators, the GSMA, enablers, and SAP Mobile Services, a division of SAP, span-ning the last three to four years. This guide tries to capture a snapshot of IPX developments while touching on concept, design, services, and scope of the technology.

In reviewing this mobile operator guide, you will be able to take away thoughts about related future development that might help you shape your roaming strategy. The history should help you decide on a clear direction, equip you to drive deployments and revenue, generate new revenue streams, and plan for LTE roaming based on IPX. This guide is intended to help not only those working with mobile service and wholesale providers, but also those working in the telecom-munications industry as a whole. It is meant to provide you with insights to facilitate innova-tion, to encourage you to go beyond traditional roaming services, and to help you simplify inter-connecting among mobile operators to support your roaming subscribers.

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The IPX: The Time Is Now

proposition encompasses security and superior reliability, enabling operators to guarantee qual-ity of service for the interconnection of IP-based services. It is also open to any service providers, such as fixed or mobile players.

The IPX also simplifies commercial agreements. Today, TDM voice commercial agreements between operators are extremely complex: if one operator wants to set up a voice TDM intercon-nection with other operators, it must negotiate contracts bilaterally with each one.

On the other hand, IPX, with its hubbing principle, enables multilateral interconnections between operators, allowing them to manage one contract instead of several. On the technical side, such a hubbing principle simplifies the interconnection, as operators only have to connect to the IPX once, instead of setting multiple bilateral physical connections. This simplified connectivity reduces costs and time to market for IP-based services (see Figure 1).

Voice is no longer the core mobile service. High-speed networks such as LTE, new-generation devices, and innovation from online service providers (OSPs) have given rise to new data demand patterns and new IP-based services, with data usage rates continuing to increase sig-nificantly. However, in this all-IP world, customers will still demand the best quality of service, high reliability, and global reach for all their services.

To keep pace and stay relevant, mobile operators must leverage their existing network assets, including quality of service and interoperability. They must also evolve their business models and make significant investments in network infra-structure. The IPX helps operators tackle these challenges.

BENEFITS OF THE IPXIPX is a managed interconnection network stan-dardized by the GSMA and i3forum, the carrier organization. The IPX relies on the principles of the GPRS roaming exchange (GRX) and being a managed network (unlike the Internet). Its value

BY PHILIPPE BELLORDRE, PROJECT MANAGER, FUTURE OF INTERCONNECT, GSMA

WHAT IS THE IPX?

The IPX is an interconnection service that is offered by a variety of carriers on a competitive basis, which uses common agreed-on technical specifications and consistent commercial models. The managed network environment is traffic-engineered to support specific IP services at specific quality levels. The IPX solution is a premium quality solution that promises error-free delivery of traffic while offering the flexibility to apply an appropriate level of quality as demanded by each different class of service.

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Figure 1: What Is the IPX?

IPX IPX

IPXIPX

Mobile network operators

SmartphonesInternet service providers

Fixed network operators

Application service providers

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Voice over LTE (VoLTE) is the next big thing on the agenda. To provide a ubiquitous reach and end-to-end high-quality HD voice, a complete IP chain from one end user to the other through all the chain, including the interconnection, is required. Again, maintaining the value proposi-tion of today’s voice service – that is, quality and security – is key, as well as simplifying the voice interconnection (to accelerate time to market).

PILOTING A SUCCESSFUL IMPLEMENTATIONIn order to prepare this shift to a full IP world, the GSMA has encouraged operators to complete commercial pilots for voice over IPX interconnec-tion to prove the commercial and technical viabil-ity of voice over IPX. The first pilot was undertaken by Telecom Italia, a fixed-line operator, and Movistar Guatemala, a mobile network operator (Telefónica Group), in partnership with two IPX providers. During this pilot, the operators tested traffic in a lab environment initially to ensure that everything would work as planned. In parallel, the participants agreed on a price structure. Then the participants shifted the commercial traffic between parties to the IPX route and compared the quality of voice traffic. This pilot was a success, with no major technical problems and similar voice quality as with legacy interconnections.

IPX FOR WHICH SERVICES?In LTE networks, both signaling and bearer traffic are delivered over IP. Therefore, for LTE roaming situations, the connectivity for signaling and bearer traffic between the visited network and the home network is delivered over IP transport with a requirement for a high level of security and quality. The IPX is the perfect network to manage this quality-sensitive traffic. As such, with more and more LTE networks being launched worldwide, we saw LTE roaming gaining momentum in 2013 with agreements announced and commercial services launched using the IPX. The rich communication suite (RCS) is also on the IPX agenda. Worldwide reach is an important differentiating asset for mobile network operators and an important value proposition for mobile customers. The ability of mobile network operators to interconnect their RCS solutions is therefore critical for the success of RCS. By reducing the number of interconnec-tions (hub principle) and simplifying the complex-ity of RCS interconnection, the IPX will speed up the overall number of RCS interconnections and make RCS a truly ubiquitous service. The GSMA is currently working with mobile operators to make this vision a reality.

High-speed networks, new-capabilities devices, new competition from online service providers, and more demand for IP-based services are challenging the status quo. The IPX is part of the solution.

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NOT IF, BUT WHENWith TDM interconnectivity being very cheap and investment needed to set up IP interconnectivity, operators have been quite reluctant so far to shift their interconnectivity to IP. However, with the launch of new IP services requiring IP intercon-nectivity (LTE roaming, RCS, and VoLTE) and operators willing to leverage interconnectivity as a differentiating asset, the outlook looks bright for IPX.

About the AuthorPhilippe Bellordre joined GSMA in 2012. He is responsible for accelerating the adoption of IP interconnectivity for new services and technolo-gies across international markets. He works col-laboratively with worldwide mobile operators on the new opportunities offered by IP interconnec-tivity, such as alternative business models. Share your comments, thoughts, and updates to this article — join the conversation on SAP Mobile Services at http://bit.ly/PHPBZn.

OTHER OPPORTUNITIES PROVIDED BY IPXAmong the assets of network operators, the possibility to manage network quality of service (QoS) is key. As such, an end-to-end IP connec-tivity coupled with quality of service (end-to-end prioritization of data along the value chain) could be a worthwhile proposition for network opera-tors who wish to address future commercial opportunities – including a two-sided market – by delivering:

• Enhanced offerings and benefits for consumers • Innovations from OSPs, enabling them to differentiate and deliver their services at the consumers’ preferred level of quality

As a managed network guaranteeing quality of service at the interconnection, the IPX is well positioned to be a key element in this full QoS chain. The GSMA is currently in discussion with mobile networks to define new business models to leverage this two-sided market approach.

https://community.sapmobileservices.com/t5/LTE/The-IPX-The-Time-is-Now/m-p/817#M13

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VoIP services are expected to drive the move to an all-IP environment that will stimulate the use of IPX. Nonetheless, several factors – the exis-tence of VoIP services offered by nontelecom players, solutions such as circuit switch (CS) fall-back, the high cost of LTE implementation, and the availability of LTE devices – are slowing down the rate at which VoLTE is being introduced. These same factors are also slowing the evolu-tionary path of mobile operators toward offering VoIP services in general.

DRIVING DEMANDHowever, if VoIP services may not be considered the imminent driver of IPX deployment on a large scale, data services requiring a guaranteed QoS might serve to stimulate market demand for IPX services. LTE roaming is the perfect example. With the high-speed data transmission enabled by LTE, it might be risky to keep on applying data pricing plans for roaming traffic based on volume or usage per month. Such pricing models may, in fact, impact consumers negatively as faster data speed will significantly increase data consumption.

New pricing schemes, where charging is more in line with the transmission opportunities enabled by LTE, may be based, for example, on different guaranteed QoS levels per different service (and also per application, as may happen in the case of cloud services). In this case, IPX would be the essential enabler, being the only current solution for a QoS-guaranteed IP interconnection able to ensure seamless traffic exchange between differ-ent players on the market.

An open and flexible model for service exchange will be part of the critical path the industry will travel in order to implement VoIP.

IP is the industry standard solution to solve the interconnectivity problem by setting out common specifications for end-to-end IP traffic delivery and quality of service. On the market, there is a high level of awareness and interest in IPX. This is linked to the fact that the industry is moving to an all-IP environment, which creates the need for an interconnection enabler over a private secure network at an affordable price and with the guarantee of the required QoS.

Clearly, there are benefits to IPX, but there is currently a low level of demand for IPX services due to the low number of IP interconnections between operators on the market. This is because mobile operators are not yet launching IP data services on a large scale.

However, this is changing. There is strong evi-dence of a shift right now as the market moves toward an all-IP world. But, of course, the market and the economy have had some impact on con-tingency plans, operator targets, and – ultimately – the pace of progress.

DRAMATIC DYNAMICSAt first glance, it may seem that IPX is a chicken-and-egg situation. But that will change dramati-cally as more operators launch IP services. To understand the holdup, it’s important to under-stand the dynamics at play here. For mobile oper-ators, moving to an all-IP environment means a revolution in communications, and this implies high investments.

A Brave New All-IP WorldBY ELENA SACCO, CHAIRMAN, THE INTERCONNECTION WORKING GROUP, GSMA & SENIOR INTERCONNECT MANAGER, TIM

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COOPERATE AND INTERCONNECTThe move to an all-IP world doesn’t only present operators with a world of opportunities. There is also the increased competition from alternative service providers offering services to subscrib-ers, creating the need for operators to intercon-nect with these players. Clearly, the big question is how to implement a seamless interconnection with these parties and find a model that properly compensates all the players in the value chain.

There will be many approaches but one common objective. The operators’ task here is to find a model of coexistence and cooperation that allows them – and other players – to achieve their objectives and stay relevant. In this case, the IPX network, because of all the characteristics high-lighted above, will be the key solution to support the market’s interconnectivity objectives.

About the AuthorElena Sacco works within the Industry Relations and Roaming Division of Telecom Italia, where her areas of expertise include business development, interconnection, and roaming with a strong focus on the evolution of mobile technology lifecycle (TLC) services. Sacco chairs the Interconnection Working Group (IWG), one of the eight perma-nent working groups under GSMA. IWG brings together more than 350 members, including mobile operators, international carriers, hubbing providers, and equipment providers.

PEERING MATTERSWhen it comes to IPX, peering among IPX provid-ers is an essential element because it enables global reachability. Without full peering among IPX providers on the market, there is the risk that IPX services will be developed as silo solutions. This certainly doesn’t serve the better interests of mobile operators – or their customers. Solu-tions cannot be offered as islands, so this is exactly what operators must avoid.

Peering enables general interoperability of ser-vices on IPX between operators and multiple con-nections and global reachability via one-stop connectivity. In other words, when full peering among IPX providers is a reality on the market, operators, through just one contract with IPX pro-viders, can update connections to hundreds of operators and third-party players around the world.

Peering also enables the offering of data services on IPX at a high QoS and, above all, the migration of voice services over IP. Indeed, with the migra-tion of voice services on IP, there is clearly the need to ensure cross-border interconnectivity on a global level. Equally important is the guarantee of a level of quality related to these voice services that can be applied globally and which is compa-rable to the high level of QoS end users already experience. Worldwide peering makes IPX the key enabler of such a migration.

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to the horizon, LTE is also emerging strongly and steadily in the market landscape. This plays a role in our thinking. Moving forward, IPX would offer a flatter IP network architecture, enabling VoLTE services and supporting new services like RCS-e. This is an important consideration since OTT players are moving in the direction of VoIP services.

For these reasons, we thought IPX would be a good platform. It addresses the mobile data roaming problem we originally set out to solve, and, looking ahead, it might also deliver us an advantage when LTE is rolled out aggressively across the region. At that point, LTE roaming will need to be enabled, and IPX is certainly the right platform to facilitate LTE roaming. What’s more, IPX allows the ability to do a local breakout, which naturally provides a better customer experience to the roamer.

So, before we jump onto the IPX platform, we conducted this trial to understand its capabilities, performance, and deployment challenges. That is, what kind of quality IPX enables when we carry voice and how it performs when it carries voice traffic between two geographical territories.

With major investments in Singapore, Australia, Africa, India, Indonesia, the Philippines, Thailand, Pakistan, and Bangladesh, SingTel is Asia’s larg-est multimarket mobile operator. In July 2011 the company embarked on a trial of IPX, the first step in exploring the establishment of a private international network connecting all the Group companies, starting with SingTel Mobile (Singapore), Globe Telecom (Philippines), and AIS (Thailand). SingTel – determined to grow the business by leveraging scale, reach, and service innovation – used the trial to better understand the technology and benefits it delivers. Chief among these is connectivity to deliver interna-tional mobile data roaming and voice traffic. How-ever, an international private network also allows the rapid deployment of new applications and services, shortening the time to market and potentially increasing competitive advantage.

In my position, it is part of my responsibility to look at technology on the horizon and under-stand what it provides in terms of both service capabilities and competitive advantage to the business we operate in. In the case of IPX, we wanted to see how we can best manage our mobile data roaming costs. We identified IPX as a good platform to achieve this and, looking again

Making the Right ConnectionsBY DAVID NG, VICE PRESIDENT, INTERNATIONAL TEAM, GROUP CONSUMERIZATION, SINGTEL

Moving forward, IPX would offer a flatter IP network architecture, enabling VoLTE services and supporting new services like RCS-e. This is an important consideration since OTT players are also moving in the direction of VoIP services.

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SINGTEL CLEARLY HAS AN UNDERSTANDING OF THE BENEFITS OF IPX. INTERESTINGLY, ASIA PACIFIC LEADS IN AWARENESS OF IPX OVERALL. WHY DO YOU THINK THIS IS?As we all know, this region is seeing a shift in the market landscape due to the rise of OTT players. According to the Cisco Visual Networking Index Mobile 2012, Asia Pacific is expected to account for up to 40% of global mobile data traffic by 2016. As a result, many – if not all – operators are facing margin squeeze due to the scissor effect of diverging mobile data traffic and revenues. This forces them to think about ways to generate rev-enues and identify new services they can offer to customers. At the same time, it’s very important for us as operators to manage our bottom line. Against this backdrop, cost management becomes a key issue. If the IPX platform per-forms and delivers on its promises, then it will allow us as operators to consolidate and optimize our IP interconnectivity for delivering packetized traffic outside our network.

For example, if IPX does indeed allow us to con-solidate and deliver mobile data roaming, Black-Berry, and telepresence traffic through a single IP pipe, then it is clearly more efficient and cost-effective. This is why I believe many operators in the region are looking into exploring IPX. IPX is also seen as a way to “future-proof” the networks and support future IP services, for example, HD services such as HD voice and HD video.

LET’S DISCUSS THE IPX TRIAL. WHERE ARE YOU IN THE PROCESS, AND WHAT HAVE YOU ACHIEVED?Originally, we picked three operations in three locations – SingTel Mobile in Singapore, Globe in the Philippines, and AIS in Thailand. Each oper-ator is connected to a private international IP network with mobile services provided by SAP Mobile Services, a division of SAP, through local points of presence. To date, we have concluded the IPX validation test on delivering mobile data roaming, mobile voice roaming, and international direct dialing (IDD) voice among the three opera-tors over the IPX connection. The validation test covered a good mix of test cases based on SIP-I interconnectivity (for mobile voice roaming and IDD voice), GSMA IR87 (for interoperator SIP-I interworking) and GSMA IR35 (for mobile data roaming). I am pleased to share that the test results were positive.

The IPX trial successfully demonstrated the reli-ability of IPX as a managed private IP network that can transport multiple services within a single IP connection across different geographies (see Figure 2). What I can also share with you is that – internally – we are brainstorming and dis-cussing how to take IPX forward.

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Figure 2: Global Mobile Data Traffic Growth per Region

MEA has the highest growth rate (104%) from 2011–2016APAC* will generate 40% of all mobile data traffic by 2016

2011

Middle East and Africa (MEA) Central and Eastern Europe (CEE) Latin America (LATAM) North America (NA) Western Europe (WE)

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40.01%

22.56%

18.18%

6.83%6.54%5.88%

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Asia Pacific (APAC)

Based on data from Cisco Visual Networking Index, Global Mobile Data Traffic Forecast 2011–2016. www.slideshare.net/CiscoSP360/cisco-visual-networking-index-vni-global-mobile-data-traffic-forecast-20112016

http://www.slideshare.net/CiscoSP360/cisco-visual-networking-index-vni-global-mobile-data-traffic-forecast-20112016

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YOUR TRIAL FOCUSES ON USING IPX TO CONNECT OPERATIONS WITHIN THE GROUP COMPANY. WHAT IS IT ABOUT IPX THAT MAKES GOOD BUSINESS SENSE IN THIS SCENARIO?I think if you take the perspective of a group company, a company that has many operations across different countries, then there is an incen-tive to find a way to interconnect the operations better with each other. At the very least, it’s about making sure that the mutual customer who roams between the different countries intercon-nected via IPX will have a service experience of more-consistent quality.

LOOKING BACK AT YOUR RECENT IPX TRIAL, WHAT CAN YOU SHARE IN THE WAY OF KEY LEARNING, IMPRESSIONS, OR SURPRISES?The findings are positive. Aside from the technol-ogy, we also learned more about the talents and skills that we would need in a service team in order to offer IPX and to support it. The service team plays a very important role in delivering the service in a timely manner.

WE HAVE DISCUSSED THE BUSINESS BENEFITS OF IPX. WHAT ARE THE BENEFITS TO THE CUSTOMER?Take the case of customers who are accessing data while roaming. Their Internet traffic when they are abroad is actually routed all the way back to their home network first. In other words, the signaling and payload part of the data session is passed to the local operator’s network and then back to the customer’s home network. This presents two challenges for the operator: maintaining cost-effectiveness and providing a consistent, good experience to customers no matter where they are.

If you go through IPX, then you can solve these issues because you have the control and can deliver a desired quality of service – a level of service that also delivers a user experience the customer will enjoy. And this is where the local breakout capability I mentioned before comes into play. With IPX you can do a local breakout, which means the roamer will be able to enjoy the same level of quality as the local customer does. It’s a better experience all around.

If you go through IPX, then you can solve these issues because you have the control and can deliver a desired quality of service – a level of service that also delivers a user experience the customer will enjoy.

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OVERALL, WHERE DO OVER-THE-TOP SERVICE PROVIDERS FIT INTO THE IPX LANDSCAPE? ARE THEY A THREAT, AN OPPORTUNITY, OR SOMETHING ELSE?My personal philosophy is that there is no “forever enemy.” We can compete on one hand, but we can be allies on the other. So, yes, IPX may play a role in bringing OTT players and tele-com players together to cooperate in a slightly more meaningful way, which will also benefit the mutual customer. In my view, there are similari-ties here to open innovation, an approach and a mind-set that is all about finding ways to collaborate for mutual benefit.

About the AuthorDavid Ng is the regional technical vice president within the international arm of the group con-sumer at SingTel. In this role, he drives the regional network initiatives and strategies within SingTel to shape technology strategy and achieve synergies across the SingTel group. Prior to this, Ng was director of operations at Telkomsel, a SingTel joint venture company in Indonesia, where he was in charge of network design and operational management.

LOOKING AT THE RANGE OF WHAT AN IPX NETWORK CAN SUPPORT – NEW MULTIMEDIA SERVICES OR EVEN PROVISIONING SERVICES INTO CARS – WHAT EXCITES YOU MOST?Without divulging too much of our internal strat-egy, I would say the type of services we are going to offer are likely to be more IP oriented. There is a very good match between what we can use IPX for and how it can benefit us at SingTel as a group operator, as well as how IPX can benefit our customers.

The multimedia services are also interesting. If the analysts are correct, IPX will drive more video, more social sharing, and more visual content to our phones. Therefore, the high quality of voice and the ability to exchange video or other visual content are turning phones into a medium that is more about seeing content and seeing people than just speaking.

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• Involve vendors early – Once an operator has connected and tested a service over IPX, whether for voice, video, messaging, or another application, the operator will then be able to provide that service to the entire community over IPX. The initial testing process is funda-mental to success, and enabling infrastructure vendors early is key. Even different releases of a platform from the same vendor can result in quite different results. Ensuring equipment ven-dors are closely involved in the process of IPX network testing from an early stage signifi-cantly reduces project timelines and will enable a full service launch sooner.

• Recognize the value of community – IPX is about connecting operators with each other and with services and applications. When choosing an IPX network, an operator should consider both the range of services provided and the community of operators connected. Right now, operators may be connecting with each other to enable just one or two particular services, but over the longer term it is likely they will want to provide more.

Using IPX can reduce connectivity costs, boost service quality, and decrease the time it takes to implement new services and roaming destina-tions. Clearly, IPX should have a central role in operators’ strategies to develop and deliver future services. Here are nine key lessons to guide operators along the path to adopting IPX and maximizing the benefits:

• Choose a quality network – IPX is about far more than simply roaming data. A whole range of services, from messaging to real-time voice and video, now flow over IPX. It is therefore critical that operators choose an IP exchange infrastructure that can provide the network service levels and resilience to deliver these services and manage the different traffic types proactively.

• Plan for future capacity – The growth of roaming data volumes between mobile operators has been considerable over the last few years. When you add voice, messaging, and LTE-based ser-vices to that, it becomes clear that there is a need to plan ahead when deploying IPX. Capac-ity for a 10-million, 30-million, or 100-million con-nection may look adequate this year, but will it continue to meet demand in 18 months? Putting in the right long-term infrastructure now will enable operators to “soft upgrade” connections rapidly to meet demand in the future.

Nine Ways to Get More Value out of IPXBY JOHN CANDISH, SENIOR DIRECTOR, IPX BUSINESS, SAP MOBILE SERVICES, A DIVISION OF SAP

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• Select an IPX provider with strong accounting capability – Clearly, IPX must enable connectiv-ity of services. But it must also ensure that rev-enue streams follow. Whether connecting data, messaging, voice, or providing other applica-tions, IPX has a key role to play in accounting functions that ensure payment follows the traffic.

• Consider the commercial relationships as well as the connectivity – When testing IPX connec-tivity, it’s important to plan ahead and select the priority roaming destinations for a service. This enables an IPX interconnection to be working on the rollout of an operator’s roaming footprint ahead of the initial connection to be deployed and tested. This significantly shortens the time between IPX connectivity and the reve-nues and service benefits delivered.

By following this advice you will have what you need to make the most of your IPX deployment. Critical is having an IPX network that is truly multiservice, thus providing capacity both for existing services and for services planned in your road map. This allows operators to realize full cost savings and competitive advantage, rather than requiring them to make additional invest-ments simply to keep up with the pace of change.

About the AuthorJohn Candish is responsible for spearheading the IPX business for SAP globally. Prior to this, Candish held positions within Cable & Wireless Communications Plc, where he was responsible for the development of the GRX and messaging services. He subsequently led the introduction of GRX and MMX services into the portfolio of mobile services for SAP Mobile Services, a division of SAP.

• Plan roaming connectivity at the same time as domestic rollout – The success of roaming has set a high bar. Users increasingly expect all home services to be available when roaming. When launching new services such as LTE, ini-tial focus should include roaming as well as domestic delivery. IPX supports rapid rollout of roaming connectivity provided operators build IPX connectivity into their deployment plans for new services early on. That means operators can also achieve roaming revenues that much more quickly for new services.

• Ensure the services available over IPX can translate between systems – IPX is about enabling connectivity, which requires bringing different implementations of the same service together, especially during the rapid rollout of new services. For example, two operators may have deployed different voice switches with different SIP-I implementations. An IPX should be able to translate between these switches, ironing out the differences to deliver seamless communication.

• Choose an IPX provider with strong policy and access control – It is vital that operators who take advantage of IPX connectivity maintain control of who can access services and the poli-cies applied to that access. This means that the IPX connection cannot function simply as a “dumb” pipe connecting the various parties, but it must provide clear control of services. An IPX connection that provides “hubbing” of ser-vices, such as voice, can control which partners are able to access services, can control which originators may connect, and applies the required policies to that traffic. As the telecom world moves toward LTE and multimedia, ser-vices such as access and policy management will become even more important.

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VOICE ON THE RISEGlobally, international voice traffic has been stagnant for some time now. This is because customers are choosing alternative ways to stay connected. At Globe, however, this is not the case. We continue to see increased voice traffic, even though customers can also communicate using alternatives, including social media, VoIP, and text messaging.

Because of this trend, Globe clearly needed to build the capabilities to support the growth in voice traffic in a more cost-effective manner. It was also important for Globe to make it easier for many operator partners to send their voice traffic to our network. This is where IPX plays a role, enabling Globe to exchange international calls directly with other mobile operators. This has become a key driver for Globe’s initial IPX efforts. Additionally, operators around the world – Globe included – are moving to an all-IP infrastructure. It’s a shift that can’t be ignored.

For Globe, the capability to support customers calling across borders today – and to cope with the massive increase in mobile data use – will depend on our ability to leverage new ways of connecting and managing operator partnerships. IPX is a natural path.

The concept of IPX is particularly relevant to the Philippines, a country where Globe is also a lead-ing mobile operator, for many critical reasons. These are linked to the makeup and requirements of our local customer base. First, a sizable portion of the population lives overseas, a separation that sometimes spans several generations. Social media is one way families keep in touch over the distance, and one of the reasons why the Philippines ranks very high in the use and con-sumption of social media.

At the other end of the spectrum, the Philippines is also a top destination for business travelers and vacationers. Many tourists visit to enjoy the many scenic spots across the country’s 7,000+ islands. Obviously, people and businesses need to stay connected across boundaries. That’s where IPX comes in. It promises to make this connectivity easier for both operators and their customers.

Expanding Voice Connectivity over IPX: An Operator PerspectiveBY GIL GENIO, HEAD OF INTERNATIONAL AND BUSINESS MARKETS, GLOBE TELECOM INC.

Operators must be able to establish direct commercial and technical interconnectivity with each other, specifically cross-regional connectivity. This is why our future infrastructure plans include IPX.

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QUALITY CONTROLGlobe is well aware of this challenge and has therefore taken steps to make it easier for travel-ers and roamers to use data. To this end, we at Globe have made the customer experience a cen-tral focus of all we do. In the Philippines, Globe is embarking on an ambitious network change that will result in Globe moving to a real-time conver-gent billing and customer care platform. Globe will also be making additional investments in analytics and other back-end systems.

These are measures that will deliver customer benefit. However, Globe customers who travel overseas, or people who come to the Philippines for business or pleasure, will not experience these advantages unless we at Globe work to make interconnectivity better and easier. In other words, operators must be able to establish direct commercial and technical interconnectivity with each other, specifically cross-regional connectiv-ity. This is why our future infrastructure plans include IPX.

THE DATA CHALLENGEAt Globe we also have to adapt to the shift in customer requirements. Customers are exploring alternative ways of staying connected, and we at Globe have to support this through invest-ments in data connectivity. Unfortunately, most operators did not respond quickly enough. The existence of complicated, unpredictable, and high-priced services, together with bill shock issues, has somewhat stunted traditional voice roaming traffic. In other words, it simply hasn’t grown as quickly – or as much – as expected. On the other hand, mobile data use by business travelers and roaming customers is increasing exponentially. This growth is driven by the increased penetration of smartphones, people’s love of social media, and the constant need of users to be connected.

This boom in mobile data use presents operators with a new challenge (see Figure 3). They must work with the visited operators to ensure roam-ing customers enjoy a good user experience at home and abroad. In other words, the experience for the roaming customer should be consistent and of high quality.

Figure 3: Overview of International Roaming Technology and Operations

Initiated call

Visited operator

International transit

services

Home operator

Receiver’s home

operator

Received call

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delivers. Chief among these are a better experi-ence for customers, a lower long-run cost struc-ture for operators, and the capability to manage current and future voice and data traffic. Keep this foremost in mind, and mobile operators, like the pioneers of the past, will enjoy the firstfruits. Personally, I am looking forward to an IPX-enabled future.

About the AuthorGil Genio is head of corporate strategy and busi-ness development at Globe Telecom. He is also the head of international and business markets. These groups are responsible for sales, relation-ships, marketing, products, and support for Globe’s overseas Filipino and service provider customers, and for business customers repre-senting small, midsize, and large enterprises. Genio serves as CEO of Innove Communications and GTI Business Holdings, subsidiaries belong-ing to Globe Telecom. He is also vice chairman of GSMA Asia-Pacific.

IPX IS INEVITABLEIPX today is a given for two reasons. For custom-ers, it’s all about being able to experience the same quality overseas that they have come to expect in their home network. What’s more, the exponential increase in data use demands that the infrastructure grow to adapt to what customers need now and in the future.

For operators, IPX is an easy path to interconnec-tivity. More important, operators are moving to all-IP networks. The bottom line is that Globe believes that – in the long run – IPX provides the best path to easier connectivity. It also delivers a lower cost structure, savings Globe can pass on to customers.

Clearly, IPX offers many benefits to operators and their customers. Today the path to IPX implemen-tation is not an easy one. But the effort is well worth it. It is important to keep an eye on the prize and focus on the many advantages IPX

This boom in mobile data use presents operators with a new challenge. They must work with the visited operators to ensure roaming customers enjoy a good user experience at home and abroad.

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end-to-end management by an experienced technical project manager who works with the operators on all aspects of the interconnection and testing.

PROGRESSIVE TESTING There’s no point in carrying out functional tests before basic connectivity is established. With careful troubleshooting and monitoring, trans-port and then protocol connectivity between operators (or between operator and hub) should be done before interface testing is performed. (For example, that basic IP connectivity works should be ensured before attempting to test Diameter transactions or an actual roaming use case.) Many of the interconnectivity issues are detected during this foundation testing, which can then be followed by the desired subset of standard test suites, such as the IR.35 test suite as defined by the GSMA.1

ESSENTIAL TROUBLESHOOTING SUPPORT FOR DIAMETER TRAFFIC Good troubleshooting probes and configurable reporting are essential in finding out where, when, and how things work differently from the way they should. Most of the issues outlined in this article were identified through the use of these sorts of tools.

As a network technology, LTE has been adopted more quickly than any other in the wireless sector. Since the first implementations in 2010, operators have now deployed multiple commer-cial offerings and announced a number of deliv-ery plans. With subscribers realizing the benefits of LTE in their home networks, the demand for the same experience in roaming has required operators to move quickly in building roaming agreements and implementations.

During 2013, SAP worked with many operators around the world to enable commercial LTE roam-ing through the SAP® IPX 365 mobile service. During that time, we learned how to make operator interconnections easier for LTE roaming, summed up in the following points.

SOUND PREPARATION AND PROCESS FOR LTE ROAMING It seems like an obvious step, but the careful prep-aration and review of a list of questions that deter-mine the operator’s network LTE architecture and configuration as it relates to roaming is essential. Every problem that we’ve encountered has been covered in this list, which allows for early identifi-cation of likely issues as well as an efficient means of sharing information between roaming test parties. Efficiency is further improved through

Best Practices for LTE RoamingBY RUSSELL J. GREEN, CTO AND VICE PRESIDENT TECHNOLOGY GROUP, SAP MOBILE SERVICES, A DIVISION OF SAP

1. “IR.35: End-to-End Functional Capability Test Specification for Inter-PMN GPRS Roaming,” GSMA, May 2011.

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EPC DESIGN AND IMPLEMENTATION DIFFERENCES We’ve found that introducing roaming helps operators review their implementation and, in some cases, their design choices underlying their LTE networks. Examples of these include the following cases:

• LTE/3G coexistence configurations with com-bined MME/SGSN, ensuring that identified potential LTE roamers from valid networks authenticate only against LTE and don’t get unnecessarily roamed onto the 3G network. This requires attention when used in conjunc-tion with circuit-switched fallback to make sure that intentional fallback to the 3G network is performed when required.

• Incorrect configuration of APNs and associated DNS IP addresses to conform to the known IP addresses that are allowed to query the home DNS server.

• Modification of QoS and session parameters to force correct handset behavior in a visited net-work. Some implementations transmit invalid attribute-value pairs (AVPs) that don’t matter in the home network but can cause issues in the visited network. Requested bandwidth values, wild-carded APNs, and PGW selections are examples of erroneous values in roaming.

ADHERENCE TO STANDARDS TO EASE INTERCONNECTION By definition, interconnection requires a common means of communication between roaming operators, and the latest standards provide this mechanism. Local implementations don’t always keep to these standards for initial deployments, as they aren’t all relevant for only-in-network traffic. This divergence can widen due to the rush to get implementations done and as a result of early deployments based on older specifications. Examples of problems that we’ve solved in this area include:

• Routing by IMSI rather than routing by realm – Some operators route locally by IMSI rather than by the standards defined for the 3gppnetwork.org root-domain-based realm. This has to be translated in the Diameter inter-working function to the standard realm to allow other operators to understand it.

• Use of nonstandard realms – Similarly, some operators abbreviate or change realm domain names. These too have to be translated to con-form to specified configurations in order to enable interworking.

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While there are many potential interconnection issues to manage, increased operator experience with both LTE and roaming interconnectivity partners means that LTE roaming interconnec-tions can be established quickly. The ecosystem of roaming partners is growing rapidly, thereby enriching the connected lives of mobile subscrib-ers around the world.

About the AuthorRussell J. Green is responsible for product and service strategy, development, and support as well as professional services, operations, and customer support. Prior to joining SAP, he held several senior management positions at VPIsystems Inc., 724 Solutions, Tandem Computers, and Digital Equipment Corporation. Join the conversation on SAP Mobile Services here: http://bit.ly/1nxcxcA.

PREPARATION OF RESOURCES TO GET THE JOB DONE QUICKLY Not just the technology implementations, but the efficiency and progress of the interconnection work depends on the skill and experience of the operator staff working on the project. Where staff have been allocated time to prepare and gain the experience to carry out interconnection work as part of a structured project, progress is made quickly. Conversely, if an engineer is tasked with making interconnection happen in addition to his or her normal production duties, the test and interconnection work won’t get priority or pro-ceed as required.

LTE interconnectivity and roaming require major interfaces (see Figure 4). The S6a Diameter inter-face (and S6d for 3G interoperability) and S8 are mandatory. The S9 Diameter interface provides additional QoS control and is expected to become a more common interconnectivity interface over time.

https://community.sapmobileservices.com/t5/LTE/Best-Practices-for-LTE-Roaming/m-p/827#M18

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Figure 4: Key Interfaces for LTE Interconnectivity

Signalling

S-GW P-GW

E-UTRAN

P-GW

SG(Local breakout)

SGi

Mobile service provider A (Visited PLMN)

Mobile service provider B (Home PLMN)

SAP® IPX 365

S5

S11

S3DEA DRA DEA

HSS

S8

V-PCRF

SGSN

H-PCRF

S6d

S9

S6aMME

SERVER PDN SERVER PDN

S1 MME

S1 u

Traffic

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The other business model being adopted is around third-party management. According to this model, the MoC outsources international traffic management to an independent third party or to an international wholesale operator. All domestic operators in a given country are then required to send and receive international calls through single or multiple international gateways (switches) managed by the third party.

Some MoCs have even gone so far as to out-source financial settlements between local operators and international operators, making the third party responsible for billing, collections, and payments. In this scenario, the third party may earn revenue from the financial transaction. In addition, the third party may be entitled to a percentage of revenue or be permitted to charge a fixed fee plus a share of revenues, or gross margin. The third party is responsible for all oper-ator activity, including negotiation of operator interconnections and traffic routing.

Under the latter model, local operators are con-cerned that their interests and the interests of the third party – the company to which traffic management has been outsourced – are not aligned. Put another way, operators believe the third party may be more focused on maximizing profit for themselves than on reducing termina-tion cost for the operator or delivering QoS for the customer.

In some African and Middle Eastern countries, the practice of outsourcing international traffic management is seen by regulators and ministries of communications (MoCs) as a means to get their fair share of revenues from local operators. The outsourcing model is considered by MoCs as a way around the notion that operators declare lower levels of international traffic than they actually handle, resulting in lower payments to the local MoC.

While outsourcing may be a way to collect “true” revenues, MoCs and regulators have to achieve a balance between enforcing license conditions without damaging competition at the consumer level and having a negative impact on QoS. The two operating models gaining traction with MoCs are monitoring operator traffic streams and out-sourcing international traffic management to third parties.

MIXED RESULTSThe first model centers on new controls and visi-bility. Some MoCs have empowered the regulator to have access to near-real-time data for all inter-national traffic – voice, SMS, MMS – managed by the local operators. To gain visibility into this data within the operator network, the regulator invests in traffic monitoring systems. The information gathered by such a system allows the MoC to cal-culate and collect correct amounts of levy from the operators. A number of traffic management and monitoring systems tailored to a specific regulator’s requirements are available on the market to make this an easy task.

Boosting Trust, Building BusinessBY RANJEET WILKHU, DIRECTOR, NEUCOM SOLUTIONS

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traffic is carried over expensive TDM networks to and from these regions in order to manage and maintain QoS (see Figure 5).

Connecting to IPX reduces this cost since the operator does not have to procure individual TDM circuits for each operator interconnection. Additional savings are gained from not having to send traffic destined for a neighboring country through Europe or the United States. For exam-ple, telephony traffic from Iran to Iraq is directed to Europe or the United States first and then delivered to the final destination, Iraq. Therefore, two separate, expensive TDM circuits are used to transport a single call. On IPX, both operators may be connected to the same IPX, which means the traffic will not trombone. Instead, it will be completed using a single hop.

Figure 5: Providers Deliver Guaranteed Quality of Service and Gain Revenue Share

IP NetworkIP Network

SP A

IPX 1 IPX 2

MNOs MNOs

$ $ $

SLA SLA SLA

Clearly, this would have obvious and negative repercussions for the operator. At one level, an operator suffers a loss in revenues. At the other end of the spectrum, the perceived lack of atten-tion for QoS could result in an increased number of customer complaints and an increased burden on customer care services.

IPX SOLVES ISSUESWhen it comes to connectivity across the region and with the rest of the world, the advance of IPX provides interesting options and opportunities. By way of background, provisioning connectivity for operators in Africa and the Middle East can be an expensive and lengthy process. The high cost of provisioning connectivity, be it through cable or satellite circuits, is driven by scarce capacity. At present, a large proportion of voice and SMS

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acceptance within the operators and mobile net-work operator community. I do not expect to see a huge uptake of IPX interconnections in Europe or the United States in the near future. In Asia, the Middle East, and Africa, IPX offers a viable option for managing multiple interconnections with a single IP connection. This has a number of advantages. Chief among these is that it would allow domestic operators the flexibility to negoti-ate their own termination rates with other opera-tors connected to IPX, while maintaining QoS. At the other end of the spectrum, MoCs and reg-ulators would have access to accurate informa-tion about traffic flows in and out of the country – visibility that builds trust and ultimately puts operators back in charge.

About the AuthorRanjeet Wilkhu is a director with Neucom Solutions, an independent telecom consulting company. His efforts to forge relationships with telecom businesses globally allowed him to make a major contribution to the successful implementation of a program under the Iraqi Ministry of Communications titled “International Marketing and Management of Voice, SMS, and MMS Traffic.”

Once IPX reaches maturity and creates ade-quately connected communities, an operator connecting to IPX will not need multiple connec-tions to multiple operators for multiple products. A single connection to an IPX will do the job. This is because voice calls, SMS, MMS, and other traffic are carried on the same single and secure network connected point to point, thus ensuring optimal routing, improved QoS, and an excellent customer experience.

The needs of MoCs for transparency and account-ability are also addressed. In other words, IPX would provide MoCs or regulators with access to traffic reporting and monitoring, giving them visi-bility into near-real-time traffic data. Such informa-tion, obtained through an operator-independent source, would further give MoCs and regulators confidence that they are paid their share of dues for international traffic. This, in turn, would build trust in the system and remove the need to invest in expensive monitoring systems or outsource international traffic management to third parties.

In Africa and the Middle East, IPX is in an early rollout phase. One holdup is the further work needed to establish standards and encourage

Operators believe the third party may be more focused on maximizing profit for themselves than on reducing termination cost for the operator or delivering QoS for the customer.

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less and transparent to the end user. There is no doubt that subscribers will notice the improved experience, whether in the HD quality of voice or the lightning-fast call setup times. Rapid rollout is only going to help maximize the network effects.

In terms of navigating the path to VoLTE, invest-ment is significant. It’s about reimplementing the voice network, only this time in the all-IP domain. It’s about transformation of a legacy circuit-switched (CS) network that was built and matured steadily over the years. In this transfor-mation process, it is imperative that operators shouldn’t have to reinvent the wheel where they don’t have to. The perfect VoLTE solution, then, would guarantee service parity and offer options for synchronization with the existing CS network, all with minimal changes or disruption to it. For example, during the initial phase of VoLTE, it is quite possible to reuse the existing prepaid sys-tems that operators already have in place and have deeply integrated into their OSS/BSS sys-tems. Whether it’s new voice services or new roaming arrangements, the new technology and new networks offer tremendous potential to redefine business models with new creative solu-tions. But the first step for operators is to start with what they have in place. This will help guar-antee an easy transition and expedite adoption.

Multiple tier-1 operators committed to launch VoLTE services in 2014. Last year VoLTE adoption was considered a matter of when, not if. Now the transformation has begun, and the VoLTE move-ment is building steam.

Over the last few years, operators have invested heavily in 4G technologies, many of which are now live. Now they are looking at means to move their core applications, of which VoLTE is going to be the most important, and services to these new 4G LTE, all-IP networks. The obvious benefit is that this will help operators to reduce cost and offer new communication services.

The foundation that will be laid in deploying VoLTE could pave the way for video and rich com-munication services, although few operators have chosen rich communication services as a way toward the goal of fully implementing VoLTE.

Since rich communication suite (RCS) services as defined by the GSMA are fairly new, it is possi-ble to implement them relatively easily. But when it comes to VoLTE, challenges abound. Voice services are still the main revenue-generating component for most operators globally, so it is important to ensure not only that the transition to VoLTE offers full service parity and consistent experience but also that the transition is seam-

VoLTE and RCS: Network Evolution and Services RevolutionBY SACHIN BAGUL, SENIOR MANAGER, PRODUCT STRATEGY AND MARKETING, MAVENIR SYSTEMS

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These networks, not restricted by legacy require-ments, could provide early models for a pure, all-IP-based wireless network.

As operators ready the VoLTE networks for launch, the need for service ubiquity and consistency while roaming is not lost on any of us. Roaming issues are an important factor in the proliferation and rapid adoption of VoLTE, so they must be solved from day one. LTE roaming, VoLTE roaming, and interconnectivity solutions are essential ele-ments that need to be thought through and imple-mented in a timely fashion. An IPX that supports the IP multimedia subsystem (IMS) and acts as a hub for RCS is crucial for interconnecting various VoLTE and RCS networks. Using an evolutionary approach, the GSMA has already put forward specifications that should help operators reuse their existing roaming agreements. Also, the GSMA’s roaming architecture for VoLTE with local breakout (RAVEL) specification aims to resolve the issue of calls tromboning all the way to the home network. With VoLTE architecture, it becomes possible to let the home network decide the path the media should take, with local break-out as a preferred way. IPX providers, such as SAP SE with its SAP IPX 365 mobile service, are actively engaged in finalizing roaming specifica-tions and leading the market, with IMS and RCS hubs ready for service.

Legacy networks will be with us for at least a few more years. Operators need to continue support-ing these networks, because it’s going to take a while for their entire subscriber bases to migrate and adopt VoLTE as the operators themselves go through that network transformation. Thus, the big challenge operators now face is how to con-tinue supporting legacy networks without much capital expenditure. Market forces demand investment in new rich services, while ongoing legacy upgrades compete for this investment capital. A good solution, then, will be the one that not only focuses on delivering these new services but also provides support for existing legacy net-works. For example, the IMS Centralized Services framework provides an option to serve legacy subscribers from the new VoLTE solution through a gateway.

So the story of VoLTE will be a story of evolution. The first VoLTE movers applied the circuit-switched fallback (CSFB) solution, which is more like voice and LTE rather than voice over LTE. As 4G coverage expands and the network becomes more resilient, we will see single-radio and dual-radio voice call continuity (SRVCC and DRVCC) solutions taking off. The migration toward a single all-IP network for all services will be aided by the IMS Centralized Services framework. There are also a few greenfield VoLTE deploy-ments planned in various parts of the world.

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About the AuthorSachin Bagul is senior manager for product strat-egy and marketing at Mavenir Systems, responsi-ble for driving product strategy and growth for the company’s RCS and VoLTE portfolio. At Mavenir Systems, he has also worked as systems architect, helping to design core network prod-ucts. Earlier, he was senior network architect at Cypress Communications and systems engineer at Nortel and Ericsson. He holds a Master’s degree in electrical engineering from Southern Methodist University, Dallas, and an MBA from Georgia Tech, Atlanta. Share your comments, thoughts, and updates to this article – join the conversation on SAP Mobile Services here: http://bit.ly/1d6h2qi.

In the not-very-distant future, this evolution should lead to a single all-IP access network that will allow operators to deliver a suite of rich com-munication services. Spectrum refarming and the discontinuation of legacy networks will be a reality. A spectrally efficient network with all-IP technology should ultimately reduce both opera-tional complexities and cost and pave the way for even richer services and innovative business models for operators, thereby reaffirming their role as leaders of the telecommunications industry.

Whether it’s new voice services or new roaming arrangements, the new technology and new networks offer tremendous potential to redefine business models with new creative solutions.

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for all sorts of IP-based services. Contrary to the public Internet, IPX is service-aware, quality-of-service enabled, and managed end to end. Con-nectivity to IPX is restricted to ensure its security.

IPX was initially perceived by the market as a net-work built just for the exchange of voice traffic. However, the industry has come to embrace the single-access concept of IPX: a single physical connection that delivers interconnectivity for all essential services.

GRX is now generally viewed not as a separate network but as a multilateral IPX transport ser-vice. This is hardly a surprise. In the established roaming architecture of 2G and 3G networks, data-roaming traffic is typically generated by traditional data applications during, for example, Web browsing or e-mailing. The purpose of GRX, then, is to route this traffic back to the home network so that the mobile service provider can count the bytes and print the invoice. But the rollout of LTE is making this, the traditional GRX model, obsolete. Why is that?

One of the biggest achievements in the history of telecommunications is roaming: wherever you go, whenever you switch on your phone, people can call you on your personal number. Roaming extends the relationship that mobile service pro-viders have with their subscribers well beyond the reach of the provider’s physical network. And here’s the important piece: wherever they go, these subscribers expect the same quality of ser-vice that they are used to in their home network.

When mobile service providers first launched IP-based data services, the need to enable these services for roaming subscribers triggered the definition and deployment of GRX. GRX is an IP backbone exclusively used by mobile service providers to exchange the data traffic generated by roamers. GRX has grown steadily since it was first launched, and it currently comprises the net-works of about 20 GRX carriers, interconnected at three peering points.

The success of GRX and the drive toward an all-IP mobile world inspired the conception of IPX, an IP backbone built to exchange IP traffic

The Wide, Wide World of the IPXBY MICHAEL VAN VEEN, GROUP DIRECTOR IPX, SAP MOBILE SERVICES, A DIVISION OF SAP

IPX delivers end-to-end management and quality of service for voice and other essential IP services, such as roaming for high-speed mobile data.

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yet, and there are two very good reasons why that is. First of all, local breakout requires the use of new technology. Service providers need to be able to exchange policy information about the users on their networks and enforce these poli-cies on their gateways. In a time when service providers are still in the middle of building and tuning their LTE networks, this is a level of com-plexity they can do without.

The other good reason local breakout is not yet available is that to allow it, service providers must trust their roaming partners to provide excellent service to their customers – at the right price. That level of trust doesn’t exist between all roam-ing partners. We would therefore expect local breakout to be enabled between trusted roaming partners only.

Unfortunately, the devil is in the details. Even though local breakout is quite obviously a very efficient routing solution for mainstream Internet services like the ones mentioned earlier, other services and applications greatly benefit from home routing via IPX. Services like voice over LTE and video over LTE would always be routed via IPX, but even for applications like BlackBerry – where the mobile service providers and their enterprise customers make sure that e-mail

A recent SAP-sponsored IPX survey of carriers, held in the summer of 2013, showed that 65% of the carriers view LTE primarily as a way to deliver higher data speeds. The availability of high-speed data connectivity in combination with the increasing capability of smart mobile devices is changing consumer behavior. More and more people use their smart mobile devices not only to enjoy HD video streaming services but also to create personal content – high-definition photos and videos – and to share this content on social media, such as Facebook.

Subscribers accustomed to fantastic network performance in their home network will expect the same level of service performance when roaming. Mobile service providers that stick to the traditional GRX business model of home-routing all upstream and downstream traffic will therefore need to make sure that they are connected to a high-capacity backbone with excellent performance characteristics – in other words, IPX.

But here’s the thing. Home-routing of all of this traffic is not particularly efficient; it would be much more efficient to allow roamers local access to the Internet by offering local breakout. Local breakout is not available in the market just

The industry has come to embrace the single-access concept of the IPX: a single physical connection that delivers interconnectivity for all essential services.

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between mobile service providers, with the aim of driving down the cost of data roaming, the EU is enforcing local breakout from a different angle. It was planned that by July 2014, subscribers would have the option of buying Internet access directly from the visited network. Thus, for the duration of subscribers’ contracts with visited networks, home network providers will not get their subscribers’ roaming business, aside from voice calling. This may well be the best conceiv-able incentive for mobile service providers to roll out local breakout with the right price packages.

About the AuthorMichael Van Veen is responsible for managing and driving the GPRS roaming exchange (GRX)/IP exchange (IPX) product line for SAP Mobile Services, a division of SAP. He began his career at KPN Telecom, where he worked on major proj-ects, including the international standardization of ISDN and fiber-to-the-home systems, and established an operational management center for the first GSM network in the Netherlands. He is the current deputy chairman of the GRXIPX Working Group, which is a subworking group under the GSMA’s IREG (interworking roaming expert group). Join the conversation on SAP Mobile Services here: http://bit.ly/1kBhNam.

traffic is kept away from the Internet – local breakout in roaming scenarios would simply not be appropriate. Service providers would there-fore need to agree for which applications local breakout would be allowed.

All of this highlights additional challenges. If all these services and applications are treated differently, how will accounting and settlement between the service providers work? How will they be able to present their subscribers with a transparent invoice at the end of the month?

In the meantime, many subscribers have an entirely different objective. They simply like to see a lower bill. Their obvious way of achieving this is by avoiding mobile service provider net-works and using Wi-Fi. In many places in the world, Wi-Fi Internet access is available at little or no cost. And even though the speed (and security) leave a lot to be desired, many sub-scribers happily settle for lower quality in exchange for a substantial cost saving.

But it is also true that Wi-Fi is not as widely avail-able as mobile service provider networks, and roamers will often find themselves using the data connectivity offered by these local mobile net-works. In an attempt to increase competition

Even though local breakout is quite obviously a very efficient routing solution for mainstream Internet services, other services and applications greatly benefit from home routing via IPX.

https://community.sapmobileservices.com/t5/LTE/The-Wide-Wide-World-of-IPX/m-p/831#M20

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Glossary

Term Definition

APN Access point name

BSS Business support system

DRVCC Dual-radio voice call continuity

EPC Evolved Packet Core

GPRS General packet radio service

GRX GPRS roaming exchange

HD High-definition

IDD International direct dialing

IMS IP multimedia subsystem, a set of specifications from 3GPP for delivering IP multimedia to mobile users

IMSI International mobile subscriber identity

IPX Internetwork packet exchange

ISUP ISDN user part

Local breakout Routing traffic of a roaming caller locally rather than taking it back to the roamer’s home network

LTE Long-term evolution, a standard for wireless communication of high-speed data for mobile phones and data terminals

MME Mobile management entity

MMS Mobile middleware services

MOC Ministry of communications, a ministry or other government agency charged with handling, managing, regulating, or overseeing communications

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Term Definition

OSP Online service providers

OSS Operation support system

OTT Over-the-top, a service where a telecommunications service provider delivers its services across all IP networks rather than through the provider’s own access network

PDN Public data network

PGW Packet gateway; PDN gateway

QoS Quality of service

RCS Rich communication suite

RCS-e Rich communication suite, enhanced

SGSN A serving GPRS support node

SIP-I Session initiation protocol with encapsulated ISUP

SRVCC Single-radio voice call continuity

TDM Time-division multiplexing

SMS Short message service

VoIP Voice over IP

VoLTE Voice over LTE

Studio SAP | 37744enUS (15/08) © 2015 SAP SE or an SAP affiliate company. All rights reserved.

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No part of this publication may be reproduced or transmitted in any form or for any purpose without the express permission of SAP SE or an SAP affi liate company.

SAP and other SAP products and services mentioned herein as well as their respective logos are trademarks or registered trademarks of SAP SE (or an SAP affi liate company) in Germany and other countries. Please see http://www.sap.com/corporate-en/legal/copyright/index.epx#trademark for additional trademark information and notices. Some software products marketed by SAP SE and its distributors contain proprietary software components of other software vendors.

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In particular, SAP SE or its affi liated companies have no obligation to pursue any course of business outlined in this document or any related presentation, or to develop or release any functionality mentioned therein. This document, or any related presentation, and SAP SE’s or its affi liated companies’ strategy and possible future developments, products, and/or platform directions and functionality are all subject to change and may be changed by SAP SE or its affi liated companies at any time for any reason without notice. The information in this document is not a commitment, promise, or legal obligation to deliver any material, code, or functionality. All forward-looking statements are subject to various risks and uncertainties that could cause actual results to diff er materially from expectations. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of their dates, and they should not be relied upon in making purchasing decisions.

ipx snapshot interconnecting services and enabling global roaming

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