Comcast: Internet traffic grew 11% in 2021 over pandemic-driven highs of 2020

Comcast said internet traffic on its cable modem network grew 11% in 2021 compared to the historic growth year of 2020.

In 2020, the pandemic forced people into lockdown, drove them to online entertainment such as streaming and online games, and made them work or go to school via the internet. As lockdowns lifted somewhat in 2021, it might have been expected that traffic would decline but instead the growth continued, said Elad Nafshi, chief network officer at Comcast Cable, in an interview with GamesBeat. In 2020, network traffic grew 32%.

“We thought that after 2020 growth, we wondered if it can really go any higher. And the answer is, yes, it can by 11%,” Nafshi said. “It’s the amazing nature of the internet that, even with all of this growth and the capacity that we’ve added in 2020. We continue to see significant growth.”

Games constituted about 11% of all downstream traffic, Comcast said. That makes sense as big game downloads often send gigabytes of data to players’ home consoles or PCs. But ongoing gaming operations such as operating online games or uploading livestreams don’t require as much data, Nafshi said. By comparison, video was 71% of traffic.

He noted that when a new Call of Duty comes out and the patches for updates come out, that leads to the downloading of massive files.

Still, he added, “Video is still the king as video still drives a lot of the downstream consumption. When you think about video, it doesn’t get bigger just when more people watch more video. It is also that the video gets bigger” as more people adopt 4K or even better TVs or mobile devices.

Comcast said that usage did shift back toward pre-pandemic levels for some users, but overall the network continued to grow.

Comcast said it invest $4.2 billion in its network in 2021 and more than $30 billion over the past decade. That means that it invested higher than average numbers in the past year, thanks in no small part to the higher demand. Comcast lifted its top tier of service from 1 gigabit per second to 1.2 gigabits per second, and it is developing technology to raise the speed to 10 gigabits a second over time.

“We continue to make significant investments into the network and so we’re certainly not resting on our laurels,” Nafshi said. “Comcast has made significant investments into the network over the last 10 years and 2021 was no different. The investments that we’re making are not just in sheer capacity, but also in the level of sophistication and intelligence that we have in the network.”

Comcast is using AI and machine learning to help increase its capacity and figure out where the bottlenecks are in its network.

The data show a gradual shift throughout the year toward pre-pandemic traffic patterns. This included peak downstream traffic once again increasing faster than upstream traffic, and peak usage times shifting from earlier in the day to later in the evening.

Peak downstream (download) traffic increased 11% over 2020 levels, while peak upstream (upload) traffic increased 5%. While less dramatic than the historic spikes of 2020 – when peak downstream traffic rose 38% and upstream traffic grew 56% – it is noteworthy that demand continued to increase even from historic 2020 highs.

2021 at a glance:

— Traffic patterns remained highly asymmetrical, as peak downstream traffic grew two times faster than upstream traffic, more closely mirroring pre-pandemic trends.
— Network asymmetry increased throughout the year, with total downstream traffic volumes 12.4 times higher than upstream for the first six months of the year, and 14.5 times higher for the last six months.
— Daily peak times shifted toward pre-pandemic norms throughout the year – peak upstream traffic times were 10 a.m. in January, 3 p.m. in June, and 10 p.m. in December.
— Streaming, web browsing, and gaming all saw the largest increases in network consumption with a 10% to 20% increase for all three categories.
— Similar to last year, entertainment activities dominated peak network traffic, with video streaming accounting for 71% of downstream traffic (same as 2020).
— Other activities that contributed to peak downstream traffic include both online gaming and web browsing which both increased their share of network usage by 1 percentage point over 2020 levels.
— Videoconferencing as a share of peak network traffic decreased slightly in 2021, remaining less than 5%.

Nafshi said in earlier interviews that the company often builds its network with growth in mind, so that it can handle surges in traffic. And today he said Comcast continues to do the work of future-proofing the network in anticipation of future demand.

In addition to smart software and virtualization technologies that increase performance and reliability, Comcast took major steps in 2021 toward 10G, which will allow Comcast to deliver multi-gigabit upload and download speeds over the connections already in tens of millions of American homes. In 2021, Comcast completed successful tests of key technologies required to deliver 10G, including a world-first demonstration of a complete 10G connection from network to modem.

“We never took our foot off the gas,” Nafshi said. “The company will continue to invest heavily in making sure that the network will always be there for our customers and always have all the capacity we need for growth.”