Multicloud (also written as multi-cloud or multi cloud) refers to a company utilizing multiple cloud computing services from various public vendors within a single, heterogeneous architecture. This approach enhances cloud infrastructure capabilities and optimizes costs. It also refers to the distribution of cloud assets, software, applications, etc. across several cloud-hosting environments. With a typical multicloud architecture utilizing two or more public clouds as well as multiple private clouds, a multicloud environment aims to eliminate the reliance on any single cloud provider and thereby alleviate vendor lock-in.
For instance, an enterprise may use separate cloud providers for infrastructure (IaaS), platform (PaaS), software (SaaS) and container (FaaS) services.[1] In the latter case, they may use different infrastructure providers for different workloads, deploy a single workload load balanced across multiple providers (active-active), or deploy a single workload on one provider, with a backup on another (active-passive).
There are several advantages to using a multicloud approach, including the ability to negotiate better pricing with cloud providers, the ability to quickly switch to another provider if needed, and the ability to avoid vendor lock-in. Multicloud can also be a good way to hedge against the risks of obsolescence, as it allows you to rely on multiple vendors and open standards, which can prolong the life of your systems.[2]
Additional benefits of the multicloud architecture include adherence to local policies that require certain data to be physically present within the area/country, geographical distribution of processing requests from physically closer cloud unit which in turn reduces latency and protect against disasters.[3][2]
Various issues and challenges also present themselves in a multicloud environment.[3] Security and governance is more complicated, and more "moving parts" may create resiliency issues.
Multicloud differs from hybrid cloud in that it refers to multiple cloud services from different vendors rather than multiple deployment modes (on-premises hardware, and public and private, cloud hosting).[4][5] However, when considering a broad definition of multi-cloud, hybrid cloud can still be regarded as a special form of multi-cloud.