Business aware traffic steering

Transcription

1 Nokia Networks Business aware traffic steering Nokia Networks white paper Business aware traffic steering

2 Contents 1. Executive Summary 3 2. Static load or QoS-based traffic steering alone is no longer enough 2.1 Towards more comprehensive traffic steering 3. Traffic Steering evolves to combine network resources, services used and customer insights to maximize customer value 3.1 A structured approach to dynamic traffic steering 3.2 Traffic steering enforcement from the core network 3.3 Management of traffic steering by the OSS 3.4 Dynamic traffic steering between cellular and Wi-Fi networks 3.5 Management of traffic steering by the OSS 4. Nokia Traffic Steering vision a comprehensive solution 4.1 Dynamic Experience Management for optimal treatment of individual application session 4.2 Centralized CEM and OSS with Dynamic Experience Management 5. Conclusion Abbreviations Page 2

3 1. Executive Summary Simply put, the role of traffic steering is to automatically distribute traffic and subscribers across a heterogeneous network (HetNet) for maximum business value. Some objectives for traffic steering that will address this aim include: 1. Getting more out of existing infrastructure: making investments work harder to maximize revenues through personalization. 2. Automate operations: orchestrate traffic steering with no manual work and automate workflow with centralized traffic steering management. To do that, radio capabilities need to be enriched with dynamic real-time analytics and action engines as well as complemented with centralized management layer monitoring and coordination functionality. 2. Static load or QoS-based traffic steering alone is no longer enough The vast majority of operators are already using some kind of traffic steering. Some use radio network features to balance users and traffic between different frequency bands and different radio access load balancing technologies. Meanwhile, there is growing use of Quality of Service (QoS) for maximum business impact. However, the implementations are often rather static, local in one domain, or require a fair amount of manual work. Increasing network complexity and unpredictable traffic growth are forcing operators to plan ahead. How long will static or manually controlled traffic steering be enough and when is a more dynamic and automated approach required? Operators promoting customer experience management are looking to automate traffic steering to gain further Operational Expenditure (OPEX) efficiency and simplification. Page 3

4 2.1 Towards more comprehensive traffic steering Operators in different markets have varying needs for traffic steering based on location, time and event. The need for new or improved tools to plan, design and track traffic in real time is surging. Conventionally, traffic steering based on 3GPP specifications has focused on QoS and load balancing. It has been based on current cell load or, more recently, on factors such as energy saving or different treatment of service classes. Implemented in the radio and core, traffic steering has been performed using fixed parameters and thresholds to direct devices to an appropriate cell. However, traffic patterns change constantly and these fixed settings quickly become out of date leading to a decline in the effectiveness of traffic steering. The demand for ever more capacity to carry growing data traffic is being met by the deployment of LTE networks and small cells. This calls for effective ways to balance traffic between the radio access layers to optimize the user experience. In addition, Wi-Fi is becoming a vital complement to cellular networks and new tools are needed to manage how devices access and use mobile and Wi-Fi in a way that matches an operator s business strategy. As more traffic steering capabilities are implemented to handle subscribers use of the HetNet s many layers and accesses, a better way to coordinate traffic steering policies can avoid conflicting control priorities. Also, the widespread deployment of Single Radio Access Network (RAN) will call for traffic management supported by integrated Operations Support System (OSS) applications and workflows. Furthermore, conventional traffic steering or load balancing techniques do not take into account the customer experience or the value of the subscriber to the operator. With more advanced traffic steering, operators would not only be able to make use of all their network resources to the maximum, but be able to differentiate between customers and deliver the right customer experience. An analogy is how airlines are able to differentiate between customers and can offer upgrades from an overbooked economy class on a flight, to business class, based on customer value. The emphasis has now shifted from managing Quality of Service (QoS) to managing the Quality of Experience (QoE) actually perceived by the subscriber. That s because QoS Key Performance Indicators (KPIs) gathered at the transport/radio network layer are application agnostic, while high-level QoE KPIs and other metrics like Mean Opinion Score do not provide sufficient detail to enable immediate action to improve Page 4

5 the QoE of individual subscribers. One of the most promising and innovative ways to address the issue is to apply big data analytics to constantly sense and optimize the QoE of individual subscriber sessions under dynamically changing conditions. The necessary actions can then be applied automatically while the subscriber session is still live. 3 Performance with Multiflow A more advanced model for traffic steering is based on a technical evaluation of the most appropriate network and services, combined with customer experience-based traffic steering enforcement. This would enable operators to use all their network investments more efficiently, to give customers a better quality of experience, and to deliver the best personalized service experience possible to optimize the value of the entire customer base. This requires traffic steering to be executed in the radio access network together with the core network and management systems such as the OSS and the Customer Experience Management (CEM) Figure system. 1: Traffic steering functions in different levels. Network wide Traffic Steering monitoring, execution coordination and automation Traffic steering target & treatment police settings CEM Customer insights & service quality monitoring Execution coordination over all network layers & domains User Equipment Radio Access Network Core Network GHz (2G) 3G LTE Bands Wi-Fi Femto Pico Micro Idle & active mode control Load balancing Nework insights Business policy execution Subscription policy management QoS management Capabilities, measurements, Traffic Steering execution Traffic Steering execution Macro Traffic Steering enforcement Fig. 1. Traffic steering functions in different levels. 1 Nokia Solutions and Networks 2014 Confidential Orchestrations of traffic steering are also needed to ensure all Core and background colors: components and automated operations like Self Organizing Networks R 18 R 0 R 104 R 168 R 216 (SON), work together G 65 G 201 effectively G 113 G 187 and G 217 to avoid conflicts between B 145 B 255 B 122 B 192 B 218 different traffic steering priorities, such as load versus customer value. Page 5

6 3.1 A structured approach to dynamic traffic steering While traffic steering is always executed in the radio access network, the enforcement of traffic steering can be controlled from the radio access network and from the core network. Traffic steering in the RAN is executed in both Idle and Active modes. In Idle mode, subscriber devices are distributed across different radio access technologies or across carriers within the same radio technology to make best use of network resources without creating unnecessary signaling or handovers, and to deliver a good customer experience. For example, providing there is sufficient capacity in the network, premium data users may be allocated to LTE or 3G by default, while users who mainly make voice calls are allocated to the 2G layer. Also, Wi-Fi may be promoted to heavy data users or home usage according to the operator s business strategy. In Active mode, the load on the network is balanced to minimize congestion and achieve the highest utilization of network resources. This is done by firstly triggering handovers in which subscribers are passed to a more lightly loaded carrier. Should this measure be unable to avoid network congestion or maintain a set service level, devices are handed to another, less congested Radio Access Technology (RAT), providing the required service level performance is met. 3.2 Traffic steering enforcement from the core network The core network works in parallel to enforce different traffic steering policies according to network or subscriber insights provided by centralized monitoring tools. This enables specific services or subscribers to be steered to a particular radio access, including Wi-Fi. The result is more dynamic traffic steering according to the user profile and operator business strategy, enabling personalized treatment for a specific customer segment or application. For example, Access Network Discovery and Selection Function (ANDSF) can be used to offload selected users to approved Wi-Fi networks. Page 6

7 The necessary insights that support such personalized traffic steering come from the operator s CEM analytics platform and from a Dynamic Experience Management (DEM) function. DEM is applying big data analytics to constantly sense and optimize the QoE of individual user sessions in dynamically changing conditions. Necessary actions are automatically applied during the window of opportunity when they matter to the end-user s session. 3.3 Management of traffic steering by the OSS With the RAN able to run several traffic steering mechanisms, there is potential for conflicting configurations to arise. A network-wide OSS system is best placed to ensure such conflicts are avoided and to introduce more automated and more dynamic configuration of traffic steering. The radio must also be able to consider traffic class or user priority when load balancing is triggered. OSS-level management of traffic steering comprises several functions including configuration, monitoring, reporting, workflow/process engine, automation, orchestration of traffic steering actions and centralized SON functions. OSS management of traffic steering also enables a much higher level of personalization of the customer experience. Customer segmentation information from CEM systems can be used by the OSS to further govern traffic steering policies. OSS monitoring and reporting also provide the operator with information on how traffic steering affects the network, as well as insights into service quality before and after traffic steering features are activated across the network layers. Page 7

8 3.4 Dynamic traffic steering between cellular and Wi-Fi networks Mobile broadband operators are increasingly looking to integrate Wi-Fi access with their cellular networks to add capacity or coverage. Wi-Fi offers a ready-made device ecosystem, as nearly all smartphones and tablets have the technology built-in, so there is no need to invest in user devices. These operators therefore need dynamic tools to control when and where devices use the cellular and Wi-Fi layers. Access Network Discovery and Selection Function (ANDSF) is a device-based steering method that enables an operator to decide on the steering rules for subscriber groups or individual subscribers depending on parameters such as time, location and application being used. ANDSF is best suited to non-real-time Wi-Fi traffic steering, reflecting pre-defined traffic patterns and requires either native or client-based support in the terminals. Such device-based steering can be complemented by network-based steering that can direct traffic from any smart devices, whether or not they have ANDSF inside. This method offers dynamic, real-time traffic steering capabilities using triggers specified by the operator, such as 3G cell congestion or traffic classes requiring different quality of service. 3.5 An evolutionary approach to business aware traffic steering Across the market, operators are at different stages of implementing traffic steering. It therefore makes sense to adopt an evolutionary approach to achieving more advanced traffic steering. The first stage is to make the most effective use of radio resources. Then move from network operations to service operations. Then provide top service for high value customers using customer experience information in an automated, real time analytics and action execution loop. Page 8

9 4. Nokia Traffic Steering vision a comprehensive solution 4.1 Dynamic Experience Management for optimal treatment of individual application session Dynamic Experience Management (DEM), an innovation from Nokia Networks FutureWorks, combines newly developed telco-scale big data analytics, artificial intelligence and full process automation to make experience management dynamic. DEM optimizes each subscriber s application session to deliver high QoE to almost 100% of all sessions, even under high loads. This cannot be achieved by current static traffic steering methods because an automated, immediate and iterative loop between analytics, decision and optimization has been missing. The QoE enhancements can be achieved by an intelligent analytics and decision engine that in real time pinpoints the cause of issues in a subscriber s application session and decides automatically on the best corrective action. Machine learning techniques ensure ever more accurate decisions over time even when data is incomplete or new situations arise. Full process automation is then applied to immediately implement the appropriate action, such as service adaption or traffic steering. DEM involves Customer Experience Agents (CEA) deployed in LTE and WCDMA radio networks and an Analytics Decision and Action (ADA) server in the core network to run the necessary session-specific traffic treatment in real time. CEAs perform the accurate QoE measurements for every session and application. Information is shared with the ADA server, which can then predict the service degradation within minutes or even seconds. Based on this analysis and pre-defined traffic priorities, the ADA server decides on and executes the necessary traffic steering actions. Page 9

10 Figure 2: Nokia Dynamic Experience Management architecture (toinen kuvista valitaan) Part 1 Network wide Traffic Steering monitoring, execution coordination and automation Traffic steering target & treatment police settings CEM Customer insights & service quality monitoring Execution coordination over all network layers & domains User Equipment Radio Access Network Core Network Analytics Decision & Action server Business policy execution Subscription policy management Figure 2: Nokia Dynamic Experience Management architecture (toinen kuvista valitaan) Part 2 Capabilities, measurements, Traffic Steering execution Customer Experience Agents Traffic Steering execution Idle & active mode control Load balancing Nework insights QoS management Traffic Steering enforcement 1 Nokia Solutions and Networks 2014 Core and background colors: BTS Confidential SAE-GW Devices R 18 G 65 B 145 R 0 G 201 B 255 R 104 G 113 B 122 R 168 G 187 B 192 CEA R 216 G 217 B 218 ADA Internet MME OSS & CEM HSS Fig. 2. Nokia Dynamic Experience Management architecture 1 Nokia Solutions and Networks 2014 Confidential Core and background colors: R 18 G 65 B 145 R 0 G 201 B 255 R 104 G 113 B 122 R 168 G 187 B 192 R 216 G 217 B 218 Page 10

11 4.2 Centralized CEM and OSS with Dynamic Experience Management With centralized traffic steering management, operators are able to: 1. Obtain a consolidated view of the status of all radio network layers, core network gateways, defined traffic prioritization policies, and traffic steering features in use on each radio layer, including settings and KPIs. 2. Set and activate traffic steering policies. Rules can include traffic steering area, customer prioritization, service quality, network quality and customer experience triggers and what kind of traffic steering actions are executed according to different triggers. 3. Take traffic steering strategies into action. Prioritization of the order of different types of traffic steering rules that have been set up. 4. Align and optimize radio network traffic steering and load balancing features with overall traffic steering strategies. 5. Monitor the impact of traffic steering: the network usage across all layers, for example, and the customer experience or the revenue impact of active traffic steering rules. 6. See the log of different traffic steering, SON operations and actions in specific areas. Centralized management ensures that dynamic traffic steering creates business value by maintaining network performance, service quality and customer experience, and lifetime value at optimal levels, despite unexpected spikes in demand. After deciding on the traffic steering strategies and setting related rules, the actual traffic steering is done automatically and real time with DEM, constantly fine-tuning the parameters and configuration in the network and devices according to the current traffic situation. Page 11

12 Traffic steering related radio features are typically 3GPP specified (like LTE Mobility Load Balancing (MLB), QoS etc). Centralized coordination of traffic steering will connect the radio features to operators processes for optimizing customer lifetime value and network usage to achieve the right business value. Figure 3: Centralized traffic steering functions with Dynamic Experience Management Network wide Traffic Steering monitoring, execution coordination and automation Traffic steering target & treatment policy settings Definition of subscribers for high priority treatment CEM Customer insights & service quality monitoring Customer experience monitoring and analysis Execution coordination over all network layers & domains Device vs network driven traffic steering coordination Definition applications for high priority treatment Service performance monitoring and analysis Load balancing coordination across radio layers Definition of role of each radio layer Radio and core consistent QoS treatment Alignment of all automated operations, DEM and SON etc Fig Centralized Nokia Solutions traffic and steering Networks 2014 functions with Dynamic Experience Confidential Management Core and background colors: Setting the traffic steering targets is a necessary coordination function R 18 R 0 R 104 R 168 R 216 G 65 G 201 G 113 G 187 G 217 with DEM. With B 145 the B increasing 255 B 122 B 192 variety B 218 of services/applications on offer in mobile networks and with Service Level Agreement (SLA) commitments to selected subscriber groups, it is essential to define consistently, from one place, the traffic treatment targets and policies for all involved domains - network, subscription, device and application management levels. Page 12

13 With DEM, the role of CEM functions with customer experience and service quality insights become crucial. Easy and informative methods are offered for near real-time viewing of customer insight reports. For off-line analytics and future planning, historical data about insights is also needed. The customer experience analytics are also complemented with service/application performance monitoring so that all high priority traffic can be seen from one view. CEM can also efficiently monitor DEM performance in real-time intelligent traffic steering. Execution coordination over all available, alternative traffic treatment methods and radio network optimization capabilities also has a central role. Once DEM is deployed and taken into use in certain parts of the network or certain technologies, there is a need to adjust the other 3GPP based load balancing and traffic steering functions in LTE, WCDMA and GSM radio layers to avoid conflicts. It is also possible to execute load balancing between Wi-Fi and cellular layers using device driven methods. If this is used together with network driven Wi-Fi, then cellular traffic steering coordination is again needed. The automated SON operations executed in real time in network elements or, as needed, at the network management level, may also interfere or conflict with dynamic traffic steering. Therefore, the network-wide centralized coordination also covers the seamless alignment between SON and all traffic steering functions, from the same shared user interface. Page 13

14 5. Conclusion Traffic steering is growing in importance as HetNets, with their use of diverse radio technologies, become more widespread. The challenge for operators is that conventional traffic steering or load balancing techniques do not take into account the customer experience or the value of the subscriber to the operator. A more advanced model for traffic steering is based on a technical evaluation of the most appropriate network and services, combined with customer experience-based enforcement of traffic steering. This would enable operators to use all their network investments more efficiently, to give customers a better quality of experience and to deliver personalized service experience to optimize the value of the entire customer base. Nokia Networks offers a comprehensive portfolio of solutions and services that allow operators to plan strategy and solutions, deploy and optimize solutions, and maintain them at peak efficiency. Page 14

15 6. Abbreviations 3GPP Third Generation Partnership Project ADA Analytics Decision and Action ANDSF Access Network Discovery and Selection Function CEM Customer Experience Management DEM Dynamic Experience Management HetNet Heterogeneous Network KPI Key Performance Indicator MLB Mobility Load Balancing OPEX Operational Expenditure OSS Operations Support System QoE Quality of Experience QoS Quality of Service RAN Radio Access Network RAT Radio Access Technology SON Self Organizing Networks SRAN Single Radio Access Network Page 15

16 Public Nokia is a registered trademark of Nokia Corporation. Other product and company names mentioned herein may be trademarks or trade names of their respective owners. Nokia Nokia Solutions and Networks Oy P.O. Box 1 FI Finland Visiting address: Karaportti 3, ESPOO, Finland Switchboard Product code C WP EN Nokia Solutions and Networks 2014 Page 16