No major nation is gripped annually by a sporting event as much as the US is by Super Bowl on the first Sunday of every February, when two teams compete for the National Football League (NFL) championship. The exception is the FIFA World Cup Final, but only for the two nations whose teams are involved and that happens every four years. Then the summer Olympics attracts the highest overall audience, but that is aggregated across large numbers of individual events.
As it happens, Super Bowl audiences have been subsiding over the last four years having peaked at 114.4 million in 2015 and fell back a further 7% for the 2018 final to 103.4 million, according to Nielsen, with signs it may slip a little more again this year. Global audiences for the FIFA World Cup final dwarf those for Super Bowl, reaching 1.12 billion viewers in 2018 for the match between France and Croatia, compared with around 150 million for Super Bowl including those outside the US.
But in the US, that ratio is reversed, with the 2018 FIFA World Cup Final attracting 11.8 million viewers, which was down 32% on the 2014 final total largely because of the time zone difference between the two events. There is an erosion of audiences for epic events driven by growing choice of content and changing tendencies among Millennials, but that is only a slow trend and Super Bowl is still a major show piece for TV technology. Coverage rotates between the three networks Fox, NBC and CBS which encourages each one to make as big a splash as possible every three years when its turn comes around. Last year it was NBC Sports majoring on Ultra HD with 200 hours of 4K coverage provided by 106 cameras, including two SkyCam systems suspended by cables and under computer control, with one of these again this year.
This year it is CBS Sports’ turn, aiming to demonstrate how AR (Augmented Reality) and use of 8K cameras, capturing video at 7680 x 4320 resolution or four times the number of pixels per screen as 4K, can combine to improve the degree of immersion. The broadcaster would not divulge details in advance of its use of AR, which also featured in NBC’s coverage last year. CBS is though clearly going beyond the incorporation of statistics about players and other games, or overlaying of pitch markings, to allow some presentation of “what if” scenarios. The extent of these depends on how much investment has been put in to incorporate sophisticated CGI (Computer Generated Imagery), for example to create “replays” of what might have happened if certain events such as a foul had not taken place.
The use of 8K is clearer cut, being to capture the images in such high resolution that they still look good when blown up to yield close-up views of the action from the endzone. Given that 8K is overkill since humans cannot readily perceive the difference from 4K even at high viewing angles, its main use case will be for special effects and close-ups.
The other aspect of Super Bowl TV coverage is almost the opposite, local in-stadium presentation of clips and replays for viewing on smartphones. For some time, LTE Broadcast has been evaluated multicasting clips within the local cell in and around the stadium. Verizon demonstrated LTE Broadcast at two or more Super Bowls, but that has now fallen out of favor and will not feature this year, even though of course plenty of people will be accessing highlights and clips over cellular services.
This has left the stage clearer for WiFi at the stadium level and on this front consumption is still rising year-on-year. In fact, for WiFi the gains have been accelerating, partly because cellular has still been hindered by data caps, as well as throttling when usage thresholds are breached. Last year, 16.31 TB of data was transferred over the stadium WiFi network compared with 11.8 TB the previous year which was in turn up by a much smaller 1.7 TB on 2016. There was also a 59% increase in number of unique WiFi users in 2018, again a much greater rise than in previous years.
More revealing though were the usage patterns exposed by drilling down into that data, which goes a long way to explaining why in-stadium multicast has not caught on as much as had been predicted over WiFi either. Cisco may not have been the pioneer but was first to develop and deploy IP multicast for WiFi on a significant scale for some enterprise and public sector customers around 2010, for file distribution as well as audio and video conferencing. At that time many cable and IPTV operators were deploying multicast within their own networks for video distribution and Cisco envisaged this extending to Wi-Fi in large campus environments, and also stadia as an alternative to LTE Broadcast.
One problem for Cisco and others is that wireless multicast has taken much longer to optimize than had been expected, as has been acknowledged by the IEEE, associated with the greater complexity of ensuring multiple clients can access a given stream at adequate quality. Among various issues, the IEEE introduced lower modulation transmissions to optimize delivery to multiple points, but this occupied the medium longer and hampered efficient transmission of traffic using higher order modulations to nearby stations. Another problem is that multicast traffic can be delayed when power-saving mechanisms are invoked in specific clients. For these reasons multicast is still work in progress, especially in the context of video streaming at high quality. IEEE working groups such as 802.11 are engineering fixes to these issues, but some of these are only just being implemented.
Meanwhile, thorough analysis of WiFi traffic at last year’s Super Bowl revealed that most of it was not video streaming or any other application that would benefit from multicast in any case. The top application was a cloud storage app, while social media apps were also popular. It is true that video streaming apps accounted for 9% of all traffic but that was led by iTunes at 1.2 TB followed by YouTube on 145.5 GB, with Netflix and then Hulu behind that. None of those would benefit at all from multicast and the same applied to the big three social media apps, Facebook, Snapchat and Twitter, which accounted for almost 2.6 TB between them.
While WiFi traffic levels will be up again this year, the profile will be similar, leaving wireless multicast for the stadium as one of those ideas whose time has still not come and possibly never will.