Wi-Fi Calling (and Texting) For Mobile Operators How Operators Can Leverage Existing Wi-Fi Networks to Solve Voice Coverage Challenges within the Home Kineto Wireless, Inc. Worldwide Headquarters 670 N. McCarthy Blvd., Milpitas, CA 95035, USA +1 408 546 0660 info@kineto.com 2014 Kineto Wireless, Inc. All rights reserved.
Introduction By embracing new technologies to improve indoor coverage, mobile operators have tacitly admitted that not all households are well served by the outdoor cellular network alone. That an operator would openly discuss indoor coverage issues was almost unthinkable just a few years ago, but the growth in demand for mobile high-speed data services has highlighted the need to address the problem in addition to supporting an improved indoor user experience for telephony and messaging. Historically, indoor coverage solutions for voice alone had not been high on the priority list for most operators. However, the need to do something to live up to the promise of 3G/4G networks to deliver broadband mobile data to homes and businesses has led to a re-evaluation of how future investments in network capacity should be split. Until recently, the largest tool in the operator s bag had been to continue investing in new radio locations and technology in the outdoor network. Splitting cells into smaller areas and improving 3G cell capacity from initial 3G data rates through At the end of the day, it was HSDPA to HSDPA+ (and from there to LTE and LTE Advanced) were all valid clear the physics and economics strategies, yet came at a high cost in terms of network planning, site acquisition and platform investment. of the outdoor radio network could not provide a ubiquitous solution that satisfied the projected growth in demand for data capacity At the end of the day, it was clear the physics and economics of the outdoor radio network could not provide a ubiquitous solution that satisfied the projected growth in demand for data capacity from indoor users. from indoor users. Small Cells and Femtocells Happily, the introduction of femtocell technology provided a new opportunity to extend the reach of the cellular network to indoor locations. With the business model predicated on a significant reduction in outdoor network investment for new data capacity, a case could be made for the wide deployment of femtocells in the residential market, especially as they solved the problem of indoor coverage for voice and messaging services as well. However, femtocells were conceived at a time when few phones had integrated Wi-Fi radio support. During the intervening period, the rise in ownership of reasonably-priced and high performance smartphones, every single one of which has a Wi-Fi radio interface, has undermined the forecasted need for indoor data capacity, especially in the home. Wi-Fi technology itself has also evolved in this timeframe, supporting higher bandwidths (with 802.11ac based systems now supporting actual throughput in excess of 100Mbps) and more advanced services while remaining competitive in a cost-sensitive, mass-market environment. Indoor mobile users with access to a broadband Wi-Fi network (whether private or public) can now simply and reliably source data capacity from fixed network operators and, with a number of VoIP services available from third party providers such as Skype, they can experience good quality voice over Wi-Fi too. 2
Operators that were reviously opposed to the use of Wi-Fi have Ironically, it is now clear there is acceptance in the user community for Wi-Fi as a suitable method to improve voice coverage, but the need for mobile data offload has been largely supplanted by the use of Wi-Fi over the subscriber s fixed, broadband network. The net effect of this has been to all but remove any capex savings due to data offload from the femtocell business case as these savings have already largely been realized through the use of Wi-Fi on the phone. While femtocells have therefore gained acceptance as a solution, there are still questions from mobile operators relating to the operational cost of larger scale deployments. Mobile users are often unwilling to pay for either the femtocell equipment or the service, and this is why the most successful femtocell deployments to date have been where the operator has mostly or completely subsidized the service. Consequently, relatively few mobile operator s so far have made femtocells an integral part of a proactive indoor coverage strategy targeting residential usage. Those operators who are unused to supplying and remotely managing access equipment at hundreds of thousands, or perhaps millions, of customer locations are cautiously optimistic at best about the impact of such large scale deployments, especially where revised business case modeling shows marginal, if any, gain. begun to embrace the technology, not just for data offload, but more recently for voice services, too. With the business case now appearing less compelling, many mobile operators have scaled back or abandoned the residential femtocell service they had planned to offer and now focus on their use in Enterprise coverage scenarios where the business case is more compelling. Wi-Fi as a Small Cell Unsurprisingly, mobile operators have determined that Wi-Fi technology is a potentially valuable tool to reduce the amount of data carried over their outdoor networks, and the results of this new realization are beginning to appear. Operators that were previously opposed to the use of Wi-Fi have begun to embrace the technology, not just for data offload, but more recently for voice services, too. As their users have grown more sophisticated in utilizing third-party options for voice and messaging over Wi-Fi, so operators have had to begin providing similar capabilities in their own networks. Without it, they risk revenue displacement to these Over-The-Top (OTT) voice service providers. Although a potentially double-edged sword, mobile operators and their equipment suppliers have begun combining licensed and unlicensed spectrum technology in single network solutions. Putting this all together, we find ourselves in an environment where femtocells are openly marketed and deployed as tools to provide improved coverage for voice and messaging services. Yet, with a few notable exceptions, the deployments are small, and the business case for mass market residential use is marginal. Mobile users are regularly connecting to Wi-Fi networks for Internet access and to utilize OTT voice and messaging services, bypassing the mobile operator entirely. Lastly, we find the more progressive mobile operators accepting the use of Wi-Fi not just for data offload purposes, but to compete more effectively for voice minutes against OTT providers. They are doing this by enabling an improved indoor service together with competitive tariffs for Wi-Fi-connected users. In order to compete more effectively, mobile operators addressing the mass market indoor coverage problem for voice and messaging must look at technologies and solutions that enable their mobile users to access core network services directly over Wi-Fi. 3
Kineto s Wi-Fi Calling (and Texting) Solutions for Mobile Operators Kineto has developed several products to help mobile operators address voice coverage challenges within subscriber homes; Smart Wi-Fi and Smart Comms. Both are smartphone based software solutions that enable subscribers to access their standard mobile telephony and SMS/ MMS services over existing Wi-Fi networks. Whenever a subscriber with a Smart Wi-Fi or Smart Comms enabled smartphone connects their phone to Wi-Fi, the software automatically connects over the Internet back to the mobile operators core network. After authenticating and authorizing the subscriber s handset, the core network then registers the handset for sending and receiving mobile voice calls and SMS/ MMS messages over the Wi-Fi network rather than the macro cellular network. By leveraging Wi-Fi, the subscriber now has high performance mobile voice and messaging coverage in the places where they spend most their time: the home and office. Smart Wi-Fi An embedded smartphone client enabling transparent use of mobile voice and messaging aservices over Wi-Fi Kineto s Smart Wi-Fi solution comprises a software client integrated within the smartphone that redirects all mobile voice and message traffic away from the cellular network and towards the Wi-Fi radio interface, providing a completely transparent experience to the end user. The subscriber is aware that their services are being carried over Wi-Fi only through the presence of a simple icon on the interface. The look and feel of the phone, their identity in the network (e.g. their mobile telephone number) and everyday usage of the phone applications are the same whether the phone is attached to the core network over the Wi-Fi interface or over the cellular network. Subscribers continue to use the native phone and messaging apps on the phone and the embedded software client transparently moves those services over the Wi-Fi radio whenever the user is connected to Wi-Fi. 4
Smart Comms A downloadable smartphone application enabling use of mobile voice and messaging services over Wi-Fi, and much more Kineto s Smart Comms solution is a downloadable smartphone application that enables mobile operators to brand, enhance and further monetize their existing voice and messaging services. One capability of Smart Comms is to redirect all mobile voice and message traffic away from the cellular network and towards the Wi-Fi radio interface. While the Smart Wi-Fi product provides a completely transparent user experience, Smart Comms provides a new, modern user experience for subscriber use of mobile voice and messaging services when on either Wi-Fi or the macro cellular network. In addition to enabling Wi-Fi Calling, Smart Comms serves as a platform for operators to introduce a number of enhanced voice and messaging products that build off the existing mobile telephony and SMS/MMS services, including International VoIP calling, second line calling, home line calling, P2P IP calling, group messaging, and much more. Additional Highlights of Kineto s Solutions for Wi-Fi Calling The following are additional Wi-Fi Calling related highlights that apply to both the Smart Wi-Fi and Smart Comms products. All Mobile Services Once the smartphone is attached to the mobile core over the Wi-Fi radio and Internet, all of the same services are available to the user just as if they were attached in the cellular network. Voice services include Mobile Originated and Mobile Terminated calling, along with standard supplementary services, such as Call Forwarding on Busy or No Answer, Hold, and Call Waiting. Any Wi-Fi While the primary focus for Wi-Fi Calling use are private Wi-Fi The operator also has several networks already in place within subscriber homes and offices, any Wi-Fi access point may be used, worldwide: in a hotel, train station, airport, coffee options to control Wi-Fi Calling shop, business location or private home. The only requirement is that the usage. Principally, the solution can user must have authorization to use the Wi-Fi service. Plus, Smart Wi-Fi and Smart Comms are complementary to any automated Wi-Fi connection be tailored to enable access only manager in the phone. from within the boundaries of the Maintain Control Smart Wi-Fi and Smart Comms have several controls operator s home network or to accessible to the mobile user, as well as the mobile service provider. Users can constrain access to a set of choose to disable Wi-Fi Calling, or to enable it only at certain Wi-Fi locations. They can distinguish between where they wish to use Wi-Fi for Internet data only or use it Wi-Fi locations. together voice and messaging services. The operator also has several options to control Wi-Fi Calling usage. Principally, the solution can be tailored to enable access only from within the boundaries of the operator s home network or to constrain access to a set of Wi-Fi locations. 5
Regulatory Compliance To support the commercial, legal and regulatory aspects of the service, it is clear that as all user traffic traverses the operator s voice and messaging platforms, then all services may be monitored and invoiced using the same lawful intercept and billing elements used for the cellular network. Emergency calls will always be pushed to the local cellular service unless the user is not able to attach to the local network, in which case the emergency call will be directed to the Wi-Fi interface. Smart Wi-Fi and Smart Comms enable the mobile user and operator to utilize any private or public broadband Wi-Fi network for access to a full suite of mobile services in locations where the cellular signal is weak or non-existent. The user experience is no different to that of using the phone when in the cellular network, with the exception that voice quality and signal strength for indoor calling is improved and text message transfer is more reliable. Advantages over Femtocells In the few instances where femtocells have been deployed in the residential mass market, the use case has been driven solely by the demand for improved indoor access to operator voice and messaging services. While femtocells certainly demonstrate several advantageous features for this application, the cost of deployment is high and, in comparison to a Wi-Fi-based system, they are limited. Mobile Voice Core (Voice, SMS, MMS, RCS...) Smart Wi-Fi Internet Smartphone with Smart Wi-Fi or Smart Comms Application (Gives subscribers transparent access to all mobile services over Wi-Fi) As an operator-specific platform, the femtocell is useful only to those subscribers of the operator that owns it. In a single house or business whose residents or employees are contracted with several different mobile providers, it is obvious that not everyone will benefit from the presence of a lone femtocell from a single provider. But a Wi-Fi-based solution will allow any user to use an existing Wi-Fi signal in the same location to improve their signal if their operator has implemented the Wi-Fi Calling solution. For example, if a user visits a friend s house and experiences poor indoor coverage, the friend s femtocell solution will only help if both are with the same mobile operator. By implementing Wi-Fi Calling in their network, the operator therefore has an immediate advantage over others offering a femtocell-only coverage approach: their subscribers can use any Wi-Fi signal to improve the mobile service. For a complete discussion on the advantages of a Wi-Fi Calling based approach to addressing indoor mobile service coverage versus femtocells, please refer to another Kineto Whitepaper titled Turning Wi-Fi Access Points into the Perfect Femtocell. 6
Conclusion While several mobile operators have used femtocell technology to solve enterprise and residential indoor coverage problems, the business case is often marginal and deployments are limited in size. Consequently, the femtocell has often been used primarily as a retention tool for those customers at risk of churn rather than as a proactive, mass market tool to improve indoor coverage for all. Wi-Fi technology, on the other hand, is now virtually synonymous with residential and enterprise broadband use and is embedded within every smartphone sold. Therefore, the business case for leveraging Wi-Fi as an indoor coverage solution for voice and data can be considerably more positive than that for femtocells, given that: Smart Wi-Fi and Smart Comms require no long-term investment in managed CPE platforms and the support infrastructure that goes with them. The customer already owns the equipment necessary to support Wi-Fi connectivity to the operator s core. Internet-only data is offloaded directly at the phone over Wi-Fi, meaning that both the operator s cellular and core networks are offloaded from all of the data that has little value yet high associated cost. Operator-based data services continue to be processed by the operator s core network platforms. The Wi-Fi-based solution complements 2G, 3G and 4G cellular coverage. There is no modification required to the Smart Wi-Fi or Smart Comms applications and infrastructure even as the outdoor radio network evolves, thus protecting the original investment in the system. Kineto s Smart Wi-Fi and Smart Comms solutions offer secure, standards-based voice/messaging and data services over Wi-Fi to an operator s core IMS network from any broadband Wi-Fi access point anywhere in the world. Indoor coverage problems in home, business, retail and transportation scenarios are solved using the Wi-Fi signal available from one or more fixed broadband operators (and/or Wi-Fi roaming providers) at each location. 7