In the recently released Cisco Global Cloud Index: Forecast and Methodology, 2011–2016 Cisco extrapolates that by 2016, two-thirds, or 4.3 zettabytes, of the total datacenter traffic will be cloud traffic representing the lion’s share of an overall six fold growth in total IP traffic.
For those not familiar with terminology for really big numbers, a zettabyte is equal to 1000 exabytes or 10^21 bytes. And if exabytes aren’t familiar, that’s one billion gigabytes (10^18 bytes). And despite the way users perceive the way that data is used, over 70% of that IP traffic will be internal to datacenters. Datacenter to end-user represents about 17% of that traffic, while datacenter to datacenter traffic is only 7%.
While datacenter will be where the bulk of the traffic exists, Cisco forecasts that dedicated server workloads will only increase from 1.5 workloads per server (as of 2011), to and average of 2 workloads per server, while the expectation is that cloud workloads will double from the 4.2 per server average in 2011 to 8.5 workloads per cloud server.
Interestingly enough, the forecast expects the growth in cloud use to be primarily consumer driven. In 2011 consumer use of the cloud averaged 4.5 times that of business us. By 2016, the forecast is that consumers will utilize the cloud more than 6 times as much as business, with business use in 2016 little more than consumer use in 2011.
If you really want to crunch the numbers yourself, you can download the 28 pages of data directly.