Videos have become an essential part of daily life. The convenience of mobile videos allows more users to stream videos on mobile terminals. According to survey results provided by the Huawei mLAB, the viewing frequency of mobile videos is mainly one to three times, accounting for 51.4% of all viewing frequencies. Current statistics show that more than 50% of YouTube users and 75% of Facebook stream videos through their mobiles. Mobile videos are a predominant driving force behind the increase in data traffic. By 2021, the GSMA predicts that 70% of the global mobile network data traffic will come from online video services. Between 2015 and 2021, the compound annual growth rate (CAGR) of video data traffic will reach 66%, eclipsing that of any other data services, such as web pages and file sharing.
However, with the rapid development of mobile videos, there is no unified standard to evaluate user experience. Yang Kun, Service Group Leader of the IP Multimedia Committee in the Service Group of China Communications Standards Association (CCSA), emphasized at the 2016 Huawei Global Analyst Summit: "Users prefer to stream videos with an excellent experience at a moderate price, rather than stream videos with a poor experience full of frame freezing and erratic displays at a low price. A complete evaluation standard is required to evaluate video quality. Universities and institutions have conducted research on video quality evaluation in the laboratory, but the industry doubts whether the research conducted in the laboratory can represent real user experience."
Traditional networks centered on capacity and coverage are faced with challenges. A network with good KPIs may provide a bad user experience. Therefore, network construction requires a unified standard for video quality evaluation based on user experience. Operators must consider how to define and evaluate user experience with the rapid network development, and how to build and manage experience-centric networks with the increasing demands for network capabilities.
Based on U-vMOS, the Huawei mobile video solution aims to resolve issues of experience evaluation, planning, and improvement, helping telecom operators build video-centric mobile broadband networks and create business success.
U-vMOS: A new video experience evaluation standard
There are general standards of research on both subjective and objective evaluation modeling methods for multimedia services. The subjective evaluation method defines the experiment environment of subjective tests, related measurement methods, and subjective scoring standard. The objective method defines a set of algorithm models that can estimate multimedia quality using input parameters.
Using the general evaluation modeling methods, Huawei has identified the top three impact factors of video experience (video quality, interactive experience, and viewing experience) to develop a unified video experience evaluation standard U-vMOS. U-vMOS covers videos on demand (VOD) in mobile scenarios as well as live videos and VOD services in fixed scenarios. In addition, detailed network indicators have been provided for the impact factors.
In collaboration with Oxford and Peking Universities, the Huawei mLab carried out qualitative research with users, according to three measurable network indicators: video resolution, initial buffering delay, and frame freezing rate.
Quantitative research based on human factors engineering was also conducted to generate a model based on the scores of the subjective video experience evaluation and data collected from sensing measurement devices. Model training is performed using machine learning to obtain a U-vMOS formula for mobile scenarios, with a scoring system (ranging from 0 to 5 points) to clearly indicate mobile video quality.
Video coverage: A video-centric network planning method
Experience-based network planning is the inevitable evolution of traditional network planning. The target of mobile network construction has shifted from providing excellent pipes to providing a superior user experience of core services. The Huawei Video Coverage is a video-centric mobile network planning method to help operators build high-definition (HD) ubiquitous mobile networks. Video Coverage involves three key steps.
First, perform network evaluation and target setting. Specifically, use objective indicators to quantify mobile video performance, analyze video consumption habits, and precisely identify target areas to be planned.
Second, implement gap and root cause analysis. Specifically, perform problem demarcation and identify root causes in the areas whose video performance does not meet certain requirements.
Third, perform solution implementation and iteration-based optimal planning. Specifically, perform coverage and capacity planning through carrier addition, sector splitting, site addition, and new feature deployment, and continuously increase fulfillment rate through the iteration-based optimal planning.
Video Coverage helps operators improve network planning efficiency and reduce network construction expenses. Iteration-based optimal planning enhances network construction efficiency and cuts investment by reducing planning quantities and costs. Targeted planning efficiently matches market targets to network construction. The deliverables of network construction have transformed from pipelines to user experience. Video Coverage uses targeting planning to map video experience against network KPIs. Therefore, video performance can be displayed and predicted to match business targets to network construction and help operators create business success.
Video Coverage has been used for network construction across the world including Australia, South Korea, the United Arab Emirates (UAE) and Saudi Arabia. A leading UAE operator proposed the video-centric traffic strategy, aiming to provide superior HD video experience. Therefore, it used the U-vMOS evaluation system for analysis in target areas and set the network construction target of providing 1080p online video services anytime and anywhere.
After the mobile video solution was deployed, the proportion of grids with a U-vMOS higher than 3.8 increased from 60.9% to 82.4%, and the initial video buffering delay has reduced by 0.49s, successfully fulfilling the predefined targets and improving user experience. In addition, a better video experience has increased data traffic consumption by 38% within three months. Video experience has also encouraged the enhancement of network capabilities leading to an improvement in user experience on other services.
End-to-end mobile video solution accelerates business success
Video experience evaluation and network planning cannot resolve all the issues in HD video network construction. Focusing on video experience, the Huawei end-to-end mobile video solution provides various effective tools for video experience improvement to help telecom operators provide the highest quality video experience. For example, multicarrier aggregation, 4x4 multiple-input multiple-output (MIMO), and 256QAM implement the last-mile capacity improvement. Two-layer TCP proxy reduces video initial buffering delay from radio access network and packet core network sides. Content delivery networks (CDNs) are deployed in a distributed manner to shorten the distance between content sources and users. A video QoS mechanism guarantees an excellent video experience and prevents negative effects on other service experiences. Load optimization is deployed for video services in medium and heavy load scenarios. Coverage enhancement allows smooth HD video streaming in place where a GSM call is available.
The Huawei mobile video solution also supports network capability openness and comprehensive flexible charging. This facilitates the cooperation between operators and OTT providers as well as the emergence of new business modes. Operators can provide network information (such as available user bandwidth and user location) for OTT to accurately transmit proper bit rates and select the nearest server, so that users can smoothly stream videos. For example, China’s leading operator and a famous OTT content provider jointly moved the CDN downstream to the evolved packet core (EPC) gateway, which carried location information through HTTP header enrichment and assisted the video server in accurately selecting a CDN node. Therefore, the average downloads rate doubled and the end to end latency decreased by over 20%.
With the flexible charging policy, operators can deploy diversified charging modes based on different video experience, video types, time periods, and video contents. For example, a combination of free-of-charge basic experience and charging for HD experience can attract more users to try video experience. Backward charging and targeted OTT plans can create more profit margins.
In the mobile broadband era, videos have become the new core service in place of voice service. Huawei is committed to working with operators and video industry partners to establish a video standard evaluation system recognized by the global telecom industry, providing an ultimate user experience through innovative solutions and rational investment, and promoting cooperation between operators and OTT through open network capabilities as well as boosting the prosperity of the mobile video industry.
For more information, visit www.huawei.com