Analysys Mason VoLTE VoWiFi Whitepaper Mar2015 RMA01

WhitepaperVoLTE and VoWi-Fi: crucial deployment and assurance considerations for operators March 2015 Anil Rao 2015] .....2 3.............................. 2015] ...2: VoLTE connections forecast [Source: Analysys Mason..1:Polystar solution [Source: Polystar......3 VoLTE uptake will increase with LTE but the business case remains unclear The current state of LTE VoLTE forecast The cost of deploying IMS and technological complexity are inhibitors 3 3 3 4 3....2 2..................... 4 Figure 2...... 10 Figure 5.............1: LTE connections forecast [Source: Analysys Mason... Executive summary 2 2................................................................... 2015].................................. 3............... 2015] ............... 8 Figure 5.. © Analysys Mason Limited 2015 Contents ... 2015] ...............VoLTE and VoWi-Fi: crucial deployment and assurance considerations for operators | i Contents 1........ 4...................1 3........... 9 Figure 5............... 4 Figure 5....... 2015] ............................................2 Operators should focus on a holistic customer experience Deploy advanced analytics and service management applications to measure end-to-end QoS Compensate for poor coverage with small cells and VoWi-Fi 7 7 7 5.............1: VoLTE challenges [Source: Analysys Mason.... 2..... 3 Figure 2.....1 2................2 5......4: ODIN post-IMS [Source: Polystar..................1 4.......... 2015] .. 2015] .......... 2 Figure 2..........................2: Validation test methodology [Source: Analysys Mason and Polystar....... 5............3 Vendor solution overview – Polystar Group Network and Customer Insight solutions Solver ODIN 8 8 9 10 About Analysys Mason 11 About Polystar Group 12 List of figures Figure 1.3: Current state of VoLTE launches [Source: Analysys Mason........3 Operators must get it right first time VoLTE increases network complexity and presents new assurance challenges Vigorous pre-launch service validation testing can mitigate the risks IP probes will be crucial for assuring VoLTE post-launch 5 5 6 6 4....3: ODIN pre-IMS [Source: Polystar................... 10 Analysys Mason does not endorse any of the vendor’s products or services discussed in this whitepaper.........1 5........................ but will require additional call handover capabilities to VoLTE. especially for Tier 2 and Tier 3 operators. especially in developed markets. and many more in other markets are expected to follow as LTE penetration increases and coverage improves.1: VoLTE challenges Technological complexity [Source: Analysys Mason. Given the proliferation and consumer affinity for OTT voice and messaging services. Executive summary Voice over LTE (VoLTE). Single radio voice call continuity (SRVCC). has been introduced to provide seamless voice service across both legacy and LTE networks. Ultimately. Increased spectral efficiency and improved voice-domain efficiency are the main business benefits of migrating to VoLTE. operators need a robust pre-launch test and validation strategy. an uncertain business case and the high costs of deploying an IP multimedia subsystem (IMS) platform. Despite the rise of data services. voice continues to be a significant source of revenue for mobile operators. © Analysys Mason Limited 2015 Executive summary . have already launched the service.1 summarises the challenges facing VoLTE. the onus is firmly on the operators – they cannot afford to go wrong with VoLTE. while providing a clear migration path to a full IMS solution. and a post-launch comprehensive service assurance capability to assure end-to-end quality of service. in addition to the savings that can be achieved by retiring legacy 2G infrastructure. Figure 1. the next-generation voice service delivered over the LTE infrastructure. However. Exacerbating the situation is the technological complexity introduced by VoLTE. Operators who want to launch VoLTE should consider cost-efficient and lightweight IMS solutions that can enable them to quickly deploy and offer the service. Voice over Wi-Fi (VoWiFi) offers another viable solution to the larger challenge of ensuring sufficient outdoor and indoor coverage. the backbone of VoLTE. 2015] VoLTE challenges High deployment costs Ensuring QoS and customer experience Figure 1. To counter some of these challenges. for example. operators should be aiming to collectively improve the user experience of the voice service.|2 1. Many operators. continue to be significant inhibitors. is slowly gaining traction. and this is expected to grow to 2. interconnection and roaming).|3 2. there was an estimated 498 million LTE connections (handsets and mobile broadband). VoLTE. a mechanism to interwork with existing network functions to provide service continuity both in terms of coverage (supporting voice services when outside LTE coverage) and also in terms of feature support (such as emergency calls. The ability to create larger data allotments compared with 3G supported by ever more capable devices will continue to accelerate the uptake of LTE technology in emerging markets over the next five years. available at http://www.463 billion connections by 2019. The 3GPP has specified a native LTE voice service.analysysmason.1: LTE 3000 connections forecast 2463 LTE connections (millions) 2500 [Source: Analysys Mason.2 VoLTE forecast Many LTE smartphones that were early entrants did not have native support for voice services and relied on the circuit-switched (CS) network to deliver voice and SMS services either by running two radios simultaneously or through the circuit-switched fallback (CSFB) mechanism.1 The current state of LTE VoLTE is the new incarnation of the native mobile voice service delivered over LTE networks. Figure 2. At the end of 2014. The last five years have seen significant investment in and proliferation of LTE networks with mobile operators in South Korea. VoLTE uptake will increase with LTE but the business case remains unclear 2. which includes SRVCC. 1 Refer to Global telecoms market: interim forecast update 2014–2019.com/Research/Content/Regional-forecasts-/Global-telecoms-forecasts-Feb2015-RDDG0 © Analysys Mason Limited 2015 VoLTE uptake will increase with LTE but the business case remains unclear . 2015]1 2086 2000 1692 1500 1279 1000 861 498 500 0 2014 2015 2016 2017 2018 2019 2. Japan and later North America deploying LTE networks to accelerate the take-up of data services and increase revenue. In other regions. the operator would break even by harnessing the spectrum benefits. the developed Asia–Pacific region and North America will maintain their lead in VoLTE. the cost of deploying and operating an on-premise IMS solution would be about USD9 million–USD10 million3 for an initial VoLTE subscriber base of around 2. Analysys Mason estimates that for a typical Tier 1 operator. 2 Refer to OTT communication services worldwide: forecasts 2013–2018. it is expected that about 600 million smartphone users worldwide will use VoLTE as their default voice service (Figure 2.3: Current state of VoLTE launches [Source: Analysys Mason. but the business case tends to be complicated and uncertain. and the annual cost can rise to about USD45 million in 5 years. Given the perceived benefits. However. as they cannot afford such high deployment costs and long implementation times with unclear business benefits. prime among them are:  Operators can achieve increased spectral efficiency because they can free up 2G and 3G carriers by moving voice traffic to LTE networks. for a subscriber base of around 75 million. freeing up capacity and allowing them to reuse the valuable spectrum for revenue-generating data services. available at http://www.com/Research/Content/Reports/OTT-communication-services-worldwide-forecasts-20132018 3 Refer to VoLTE business cases: the value of spectrum reuse.com/Research/Content/Reports/VoLTE-business-cases-Feb2015-RMA04-RDMV0 © Analysys Mason Limited 2015 VoLTE uptake will increase with LTE but the business case remains unclear .2: VoLTE connections forecast [Source: Figure 2.5 million.3). 700 35 600 30 Number of operators 31 Users (millions) 500 400 300 200 100 25 20 16 15 10 10 5 0 0 2010 2011 2012 2013 2014 2015 2016 2017 2018 In deployment Launched Trialling Figure 2.2). In the long run.3 The cost of deploying IMS and technological complexity are inhibitors VoLTE promises important business benefits. etc. The scale of the problem becomes even more magnified in the case of smaller Tier 2 and Tier 3 operators. 2015] 2. Additionally.  Operators can harness increased efficiency in the voice domain because the LTE interface is very efficient and can support up to twice as many voice users in a given bandwidth (per megahertz) as circuitswitched services. available at http://www. 2015]2 Analysys Mason. an enhanced feature set and virtualisation. Viber. limited LTE coverage will give operators little choice but to rely on 2G and 3G networks for voice services in the near term (Figure 2. the roll-out of VoLTE services is not necessarily straightforward because it requires considerable investment in an IMS core that is designed to support multimedia sessions in an all-IP environment. one would expect a faster adoption of the VoLTE service.analysysmason.|4 By 2018. the higher voice quality promised by VoLTE adds impetus to the marketing position for operators. Following from their leadership in LTE.analysysmason. especially for those aiming to position the service against the established OTTs such as Skype. operators face a variety of network and operation support system (OSS) challenges to successfully launch. operators face the difficult task of implementing an expensive and extremely complex network technology and an unclear business case. call set-up success rates. This.  Expected signalling overloads – Operators have deployed diameter routing agents (DRA) for load balancing of signalling overload from smartphones. the IMS needs to accurately maintain the state of the call and provide control for both outgoing and incoming calls. latency. places significant pressure on operators to get VoLTE right first time.  Call handover in the RAN – In a scenario in which a user has initiated a call in an LTE cell but moved out of LTE coverage mid-call. together with the established quality of service (QoS) expectations of CS voice. Some of these key challenges are discussed below. the call must be seamlessly handed over from LTE packet-switched (PS) network to the 2G/3G CS voice network. Some of the network performance KPIs such as bit-rate. However. As calls are handed over from PS to CS voice network and vice-versa.  Call anchoring in the core network for SRVCC – As the calls can be either PS or CS depending on the radio coverage. The network has to be optimally tuned to ensure voice packets get the highest priority (assigning the appropriate QoS Class Identifier (QCI)).  End-to-end quality of service – Voice being real time in nature. Operators face a significant risk of launching an ill-conceived service and failing to meet customer expectations if they do not carefully plan for all failure scenarios. as low reliability of the connection and interference from neighbouring cells can result in dropped calls. Application KPIs such as call set-up delay.1 VoLTE increases network complexity and presents new assurance challenges Because of the inherently complex nature of the technology. Moreover. failed calls.|5 3.  Network performance – The network performance and optimisation and self-organising network (SON) capability will enable operators to monitor and assure the VoLTE service in real time. jitter and packet loss must be monitored and actioned in real time. any degradation in network performance can have a noticeable impact on call quality. voice is still the highest revenue-generating service for mobile operators. Operators must get it right first time Despite showing a declining trend. It is expected that VoLTE will further increase the signalling load and any DRA failure will have a significant impact on the VoLTE service. 3.  Assuring QoS in the RAN and at cell edge – Assuring QoS in the RAN is a significant challenge for operators. Call drops must be avoided and the expected call quality in terms of latency and QoS must be maintained. all calls must be anchored by the IMS. © Analysys Mason Limited 2015 Operators must get it right first time . dropped calls and mean opinion score (MOS) can be used for further analysis to both reactively and proactively assure the service. which is further accentuated as customers move to the edge of the cell. operate and assure VoLTE. customers still expect a high-quality voice service. they must consider a plethora of factors and scenarios. IP voice traffic and the related protocols to support voice transmission over a PS network. the different call scenarios that are possible. mobile attach and bearer creation. which can include mass call or session generation. 3. among others. If operators intend to position VoLTE as a best-in-class solution. IP probe solutions cover most of this functionality and are going to be an important part of operators’ service assurance strategy. the control plane is used for authentication. then they must be able to guarantee that it performs as expected. The regime needs to cover a wide range of both test methods and scenarios. while the SIP signalling and the IP voice traffic is carried over the user plane. for example. VoLTE to 2G/3G/CDMA and vice-versa. Furthermore. Consider. E911 and lawful intercept. In VoLTE.|6 3. This can be achieved through the use of algorithms such as PESQ/POLQA and PEVQ. for both voice and video. Probe solutions that are capable of correlating controlplane and user-plane data for effective troubleshooting will be needed. including handover between different networks and domains. Individual test cases and scenarios should also be complemented by high volume stress testing. such a test regime should include the simulation of individual user sessions from both real and test devices. Flows can be examined at various points across the network to verify compliance with relevant standards and interworking. As VoLTE promises higher quality service. core network and RAN. A network call set-up for VoLTE requires significant levels of co-ordination among disparate network elements. © Analysys Mason Limited 2015 Operators must get it right first time . Test devices can be simulated in sophisticated equipment that can generate both signalling and media plane traffic.2 Vigorous pre-launch service validation testing can mitigate the risks Operators can partly minimise the risks by following a thorough service validation test regime before the launch. For example. VoLTE to PSTN and vice-versa. to ensure consistent end-to-end performance. In doing so. many legacy network components must be tested because of the software upgrades related to SRVCC. such as VoLTE to VoLTE. it is also essential to validate session quality. A call handover scenario (SRVCC) is even more complex as it involves more signalling complexity between the IMS.3 IP probes will be crucial for assuring VoLTE post-launch As operators look to launch VoLTE. Signalling for attach registration and call control must be monitored for troubleshooting. they must deploy and scale IP probes that are capable of monitoring the key interfaces. Admittedly. 4. and more American operators such as AT&T and Verizon have announced plans to launch the service to complement their VoLTE plans. Operators should focus on a holistic customer experience The ability to offer a high-quality voice service and superior customer experience is vital for operators to be able to compete with the OTT VoIP service providers.1 Deploy advanced analytics and service management applications to measure endto-end QoS By design. © Analysys Mason Limited 2015 Operators should focus on a holistic customer experience . strengthens the confidence of operators in rolling out the service and increases the chances of accelerating the service take-up. The launch of the new iPhone 6 with iOS 8. From an end-to-end perspective. VoLTE with SRVCC utilises both the PS and CS network infrastructure to deliver the voice service. and vice-versa. 2G/3G and IMS components. operators can also reduce pressures on the LTE bandwidth and capacity. they will need a two-pronged strategy to ensure that customer experience is not compromised. Operators can achieve this by supplementing their macro network by deploying small cells in dense locations. Operators must plan to minimise the network blind-spots and provide sufficient coverage at the most likely places where customers are expected to use the VoLTE service – for example. and minimising opex associated with large numbers of small cells. central business districts or sports arenas. Marketing teams would also potentially benefit from this insight. From a customer experience management perspective. which supports VoWi-Fi (and VoLTE). causing coverage and capacity problems for mobile operators. where a call was initiated in LTE and handed over to the CS network. the solution needs to be in a position to perform root cause analysis and cross-domain correlation across LTE. network and traffic planning. Calls handed over to the CS voice network will need to be monitored and assured for the QoS that has been traditionally delivered. Both Three UK and T-Mobile USA have live VoWi-Fi services. a VoLTE service management application providing percustomer KPI reporting as well as additional guidance on likely reasons for service degradation enables both operations and customer care personnel to better troubleshoot issues and manage customer relationships effectively. However. VoWi-Fi solutions only address the coverage issue from the voice service perspective. As VoLTE becomes more mainstream.2 Compensate for poor coverage with small cells and VoWi-Fi Mobile data consumption will continue to grow rapidly as the LTE networks expand. Such reporting applications enable other internal organisations such as network engineering to better plan and optimise network resources for optimum customer experience. providing the necessary backhaul.|7 4. By allowing customers to use the Wi-Fi access network for voice calls. 4. As operators prepare to launch VoLTE or scale up the service. and the take-up of smartphones and other mobile broadband devices increase. deploying small cells is a complex and expensive exercise as operators may encounter many challenges such as identifying appropriate locations for installations. at indoor and outdoor locations such as city centres. operators will be particularly hard pressed to address this issue because an inability to make voice calls due to poor coverage issues will result in poor customer experience and cause churn. and operators will still need to deploy small cells to tackle the broader issue of coverage for data services. Mobile operators can also address the coverage issue for voice by implementing the VoWi-Fi service and support seamless call handovers between the LTE network and Wi-Fi. Polystar Group offers a complete range of solutions to support the entire lifecycle of VoLTE. Polystar’s solutions enable:     Operators to rapidly launch VoLTE/VoWi-Fi services Validation and verification of VoLTE/VoWi-Fi Real-time service assurance for VoLTE/VoWi-Fi Actionable intelligence to enhance customer service.1 Network and Customer Insight solutions The Network and Customer Insight solutions enable operators to monitor the overall performance of the VoLTE network. 2015] 5. including service deployment. growth and monetisation. and the service is delivered with the required level of performance. enable rich services to be delivered and ensure that customer experience is optimised.1:Polystar solution [Source: Polystar. Figure 5. Polystar’s solutions have been specifically designed to minimise the risk of service launch. Vendor solution overview – Polystar Group It is clear that the launch of VoLTE is not without challenges. To successfully launch VoLTE/VoWi-Fi. service assurance. validation and testing. capabilities and resources to ensure that the investment objectives are met. Among many vendor options available in the marketplace.|8 5. it is essential for operators to build partnerships with vendors that can offer the necessary tools. one vendor is the Polystar Group. Operations personnel and engineers can obtain an end-to-end view of the network through a wide © Analysys Mason Limited 2015 Vendor solution overview – Polystar Group . operators can execute all required tests for a successful VoLTE and SRVCC implementation from a single platform. Quality measurements for voice and video should be carried out during all the phases to determine that QoS does not degrade with increased traffic volume. © Analysys Mason Limited 2015 Vendor solution overview – Polystar Group .2 Solver Implementing VoLTE with SRVCC is a complex process because existing networks and nodes require upgrades and configurations to support new functions. By planning and executing a thorough test strategy. The solution consists of both probes and call-trace applications. including IMS. real-time insight from the network. presented in the form of clear visual dashboards and displays. enabling operators to detect and act on potential network issues with a minimum of delay. The solution provides detailed. it is sufficient to simulate a few users as the volumes are enough to test basic functionality. test cases can be built and executed within minutes and without the need for extensive training. Upon discovering KPI threshold breaches on the dashboards. With Solver. Additionally. Solver supports key IMS interfaces as defined by 3GPP. operators can minimise the risks of failure. allowing for easy correlation of signalling across different interfaces. 5. such as Mb.|9 range of KPIs and parameters. all monitoring is performed with the same components.2: Validation test methodology [Source: Analysys Mason and Polystar. The dashboards offer high levels of flexibility allowing users to modify existing reports and to create dashboards of their own. to validate all the network functions to ensure end-to-end functional compliance. Ix and Iq. 2015] Performing tests with real terminals (user equipment) can be a time-consuming task. In the first phase of the implementation. Figure 5. as well as voice and video quality algorithms. Operators can use the Network and Customer Insight solutions in tandem to quickly troubleshoot emerging network problems that could impact VoLTE/VoWi-Fi services. The second phase of the testing could include several hundreds of users. It supports all relevant signalling and protocols/interfaces for VoLTE/VoWi-Fi. operations personnel can drill deeper to view granular network level information captured by the probe. with support for RTP/SRTP and H. Using the intuitive user interface.248 protocols. The ability to gain an end-to-end network view as well as deeper network insight enables operators to effectively monitor and troubleshoot VoLTE and VoWi-Fi services. The final phase will focus on a full system load test to make sure that all network nodes and functions deliver the planned capacity. By using simulated terminals and a simulated RAN. the functions in the core network can be validated much faster. New nodes and functions also need to interact seamlessly with existing ones and a multi-vendor network environment adds further complexity to the challenge. This phase will form the crux of the validation strategy as it will include testing of the numerous legacy network functions that have been upgraded to support SRVCC. MMTEL. SRVCC and Service Centralisation and Continuity.4: ODIN post-IMS [Source: Polystar. CAPv2. including MAP. Dx. the integration of ODIN requires significantly less time.3 and 5. Odin is compliant with a range of 3GPP standard interfaces. SIP (IMS profile) and ISC. Because ODIN comes as a single node. costing much less to integrate into the network environment than traditional IMS solutions. either on-premise or delivered from the cloud. ODIN supports VoLTE (IR. Figure 5.92). Gy. It can be integrated into the core network as a standard SS7 node. Sh. Currently. running on commodity hardware. This flexibility provides a smooth deployment capability with a clear evolution path should the core be upgraded to support a full IMS. enabling operators to quickly launch VoLTE and VoWi-Fi services. ODIN can assume the role of an application server in the IMS network. combined S-CSCF and AS or as a standalone IMS AS. It is fully virtualised.3 ODIN ODIN is an out-of-the-box software platform that provides a cost-efficient alternative to the expensive IMS.4 depict the pre-IMS and postIMS deployment scenarios of ODIN. VoWi-Fi. offering flexible deployment options. Pre-IMS Figure 5.3: ODIN pre-IMS [Source: Polystar. Cx. It is also future-proof because. if and when the operator decides to deploy a complete IMS platform. In addition. 2015] Post-IMS Figure 5.| 10 5. it requires minimal integration. 2015] © Analysys Mason Limited 2015 Vendor solution overview – Polystar Group . Figures and projections contained in this report are based on publicly available information only and are produced by the Research Division of Analysys Mason Limited independently of any client-specific work within Analysys Mason Limited. in whatever form. Analysys Mason Limited shall not be under any liability for loss or damage (including consequential loss) whatsoever or howsoever arising as a result of the use of this publication by the customer. He has published research on IP probes.com • www. UK.| 11 About the author Anil Rao (Senior Analyst) is a member of Analysys Mason’s Telecoms Software research team and is the lead analyst for the Service Assurance programme. the presence of a term. agents or any third party. Analysys Mason Limited maintains that all reasonable care and skill have been used in the compilation of this publication. does not affect its legal status as a trademark.analysysmason. recording or otherwise – without the prior written permission of the publisher. However. real-time network analytics and the importance of service assurance in reducing churn and improving customer experience. Analysys Mason Limited recognises that many terms appearing in this report are proprietary.com/research Registered in England No. However. © Analysys Mason Limited 2015 About the author . 4 Published by Analysys Mason Limited • Bush House • North West Wing • Aldwych • London • WC2B 4PJ • UK Tel: +44 (0)20 7395 9000 • Fax: +44 (0)20 7395 9001 • Email: research@analysysmason. He holds a BEng in Computer Science from the University of Mysore and an MBA from Lancaster University Management School. The opinions expressed are those of the stated authors only. his servants. all such trademarks are acknowledged and every effort has been made to indicate them by the normal UK publishing practice of capitalisation. focusing on producing market share. No part of this publication may be reproduced. forecast and research collateral for the programme. 5177472 © Analysys Mason Limited 2015 All rights reserved. photocopying. mechanical. stored in a retrieval system or transmitted in any form or by any means – electronic. About Polystar Group Polystar Group enables communications service providers to achieve excellence in CEM. big data analytics. serving customers in over 50 countries. as well as the software. Since its inception in Stockholm in 1983. please visit www.com. Polystar’s real-time Network and Customer Insights uncover a goldmine of data. track and forecast the different services accessed by consumers and enterprises.analysysmason. infrastructure and technology delivering those services. For more information.polystar. and evolved to a global presence. service assurance. Polystar is recognised as one of the fastest-growing companies in Sweden.com/research. which yields indispensable insights to CSPs. network monitoring and high performance testing.  Research clients benefit from regular and timely intelligence in addition to direct access to our team of expert analysts. © Analysys Mason Limited 2015 About Polystar Group .| 12 About Analysys Mason Research  We analyse. For more information. Polystar helps CSPs to simplify their CEM strategies and drive operational efficiency through real-time network analytics. please visit www. Polystar has experienced continuous and sustainable growth.