Breaking the myth: fast download speed is not equal to good video experience in the US

Ever since smartphone users started consuming video on their phones, it’s become a common assumption that fast download speeds translate to a good mobile video experience. While speed is certainly an indicator of video experience, it is not the only factor to determine the quality of video we see. In fact, when mobile users have access to double-digit speeds, the throughput of the connection becomes less important in determining video experience, while other characteristics and configurations of the networks become more important.

In this analysis, we took a closer look at the regional scores of the four major U.S. networks (from our latest U.S. country report), and observed that across 59 metropolitan areas, operators ranked differently in Video Experience and Download Speed Experience in all but one city.

Faster speed does not always mean better Video Experience

San Antonio was the only market where the four national operators ranked the same in both Download Speed Experience and Video Experience. Although our users on Verizon’s network experienced the best download speeds in just 12 of those 59 cities, the operator won outright our Video Experience award in all except three cities, where it tied for the lead with T-Mobile. AT&T won our Download Speed Experience award in 13 cities, yet the operator was always behind Verizon — and often behind T-Mobile and Sprint — on Video Experience. Our T-Mobile users enjoyed the fastest Download Speed Experience in eight cities, though the operator only managed to draw on Video Experience in three markets, while falling behind Verizon in all other metropolitan areas.

Seattle provides quite an interesting case: AT&T won by far our Download Speed Experience, with our users on its network enjoying on average 34 Mbps in download speed, 8 Mbps more compared to our Verizon users, who on average experienced 26.2 Mbps in download speed. Nevertheless, in Seattle we measured AT&T with the lowest Video Experience score, earning 49.2 points out-of-100, while Verizon was the only operator to earn a Good Video rating (55-65 points) with a score of 59.7 points.

Despite AT&T earning a second place in our Download Speed Experience metric in Los Angeles, the operator earned the lowest Video Experience score of 47.8 points, 13.8 points behind the metric winner Verizon, which gained a score of 61.6.

Faster speed does not always mean better Video Experience

U.S. smartphone users are not the only ones witnessing this discrepancy between download speeds and video quality experienced on mobile networks. In a recent analysis of mobile experience in Malaysia, we found that a 40% decrease in 4G Download Speed on U Mobile’s network reflected only a 5% decrease in our 4G Video Experience score.

Download speed has been the focal point of the mobile industry to describe mobile network quality, but speed is just one of the factors at play when smartphone users connect to mobile networks. Speed certainly affects Video Experience — for example when users watch higher quality videos they will require faster connections for a seamless stream — but as this analysis shows, speed cannot alone explain smartphone users’ Video Experience on different mobile networks.

Latency plays an important role in ensuring quick load times, and a consistent throughput can help avoid buffering during video streaming. Peering links with content providers, intelligent caching systems, and other network optimization practices — for example, restricting video resolution or throttling a specific Content Delivery Network (CDN) such as YouTube — can also have an impact on smartphone users’ Video Experience, which cannot be revealed by a speed test.

At Opensignal, we measure smartphone users’ real Video Experience with a direct video test. We are directly measuring video streams from end-user devices and using an International Telecommunication Union (ITU)-based approach to quantify the overall video experience for each operator. The videos tested include a mixture of resolutions and are streamed directly from the world’s largest video content providers, ensuring our metric describes real-world user’s experience.

Mobile video traffic now accounts for more than half of all mobile data traffic and Cisco forecasts it will reach nearly four-fifths of the world’s mobile data traffic by 2022.

As video becomes the main content consumed by smartphone users, Opensignal’s data demonstrates that a measure of just speed cannot alone indicate the quality of video streamed by users. To understand the mobile video experience, the mobile industry must use direct tests of video streaming.