Global cloud traffic from enterprise data centers to public cloud providers will quadruple between now and 2019, according to projections by Cisco Systems in its fifth annual Global Cloud Index.
That means the amount of traffic will increase from 2.1 zettabytes in 2014 to 8.6 zettabytes in 2019. A zettabyte (ZB) is 1,000 exabytes, which in turn is 1,000 petabytes.
Global cloud traffic represents part of all data center traffic, which will also grow at a fast pace, but not at the pace of the cloud segment. It is expected to triple during the same period, growing from 3.4 ZB in 2014 to 10.4 ZB in 2019.
For perspective, think of 10.4 ZB as the equivalent 6.8 trillion high-definition movies viewed online or 144 trillion hours of streaming music. That many hours of music would be enough to supply every person on the planet with 26 months of continuous music, if the world population hits 7.6 billion in 2019, as the United Nations expects.
[Want to learn more about how Asia is adopting cloud computing? See IBM, Microsoft, AWS Eye India As Next Cloud Hub.]
The projected global cloud traffic and overall data center traffic are statistics of particular interest to Cisco customers who are telecommunications and data center services providers. Each year Cisco assembles statistics from third-party market researchers, which it refers to as "syndicated resources," and combines them with its own knowledge of data center use and data center traffic, explained Thomas Barnett, director of service-provider thought leadership at Cisco, in an interview.
"The largest starting point is looking at the number of servers in data centers worldwide" and determining the number that are virtualized versus traditional, or unvirtualized. Cisco also looks at how many applications each server is running. In 2014, traditional data centers were running two workloads per physical server and cloud data centers were running 5.1 workloads per server. Cisco says by 2019 these measures of workload density will grow to 3.2 workloads per server in traditional data centers and 8.4 per server in cloud data centers.
While Cisco says it makes each year's projections with a consistent process, it acknowledges other parties doing the same estimates could come out in different places. "There's almost as much art to it as science," conceded Barnett. Still, few are investing the effort that Cisco does to derive such figures.
Cisco projects, for example, that the Internet of Things, which it redubs the "Internet of Everything," will generate more traffic than anything else. Not all of it, however, is headed to public clouds for processing, though it may be headed to cloud storage. IoT applications will generate 43.2 ZB a month (or 507.5 ZB a year) by 2019, or 49 times the amount of data center traffic (10.4 ZB). That's up from 134.5 ZB a year in 2014.
By global region, North America will generate the most cloud traffic at 3.6 ZB by 2019, followed by Asia-Pacific at 2.3 ZB and Western Europe at 1.5 ZB. But all areas of the globe will experience a 30% increase in cloud traffic by 2019. The growth of cloud computing is a global phenomenon, the index said.
The index projects that public cloud workloads are going to grow at a 44% compound annual growth rate from 2014 through 2019. Private clouds inside enterprise data centers will grow at the much slower rate of 16%. That means by 2019, 56% of all workloads will be running in the public cloud. In 2014, that figure was 30%, Barnett said.
The most popular, adopted service (in the NIST definition of the cloud model) will be software-as-a-service, with 59% of cloud workloads running in SaaS by 2019, Barnett said.
Thirty percent of workloads will be infrastructure-as-a-service in 2019, and 11% will be platform-as-a-service.
In the consumer area, the index found 73% of consumer data in 2014 was still stored on PCs, but that's shifting toward smartphones and other devices. By 2019, the majority of stored data will have moved to mobile devices, resulting in more consumer data in cloud repositories.
But Internet and consumer device use will continue to grow more sophisticated in terms of traffic management. Content delivery networks will keep striving to deliver more and more content from Internet servers that are close to the requester. "Someone in L.A. requesting a movie is not going to be connected to a server in New York. The more localized the content traffic is, the more that takes away from the need to communicate with the core of the enterprise data center," Barnett noted.