OpenStack

OpenStack is a set of software components providing common services for cloud infrastructure, and beyond standard infrastructure as a service it adds orchestration, fault management and service management to keep user applications highly available.

Its scale is documented through named deployments rather than asserted, and the examples are unusually concrete. Walmart runs its e-commerce on an OpenStack cloud with more than 170,000 cores across over 30 regions, sized for peaks such as Black Friday. China Mobile, serving more than 800 million subscribers across 3 million base stations, is building the largest network functions virtualisation network on OpenStack with over 50,000 servers. Blizzard Entertainment uses OpenStack autoscaling to run games including Overwatch.

Those three cases matter because they are different problems. Retail e-commerce needs elastic capacity for predictable spikes, telecoms needs carrier grade reliability across distributed infrastructure, and games need autoscaling against unpredictable player demand. In total OpenStack is trusted to manage more than 40 million cores across dozens of industries.

The project is supported by a substantial vendor ecosystem. Ericsson's Cloud Execution Environment is a telecom grade virtual infrastructure manager based on OpenStack and OPNFV, deployed with more than 100 operators worldwide, and Red Hat contributes extensively across OpenStack and ancillary projects alongside support, training and consulting. The software itself is open source with no licence fee; cost comes from the distribution, support subscription or managed service an organisation chooses.