From virtualization to cloud computing
Before moving to this new technologies, it is crucial to understand how things work in the past before this two concepts.
A glance in the past :
To afford a service (Like running web application or mailing service), companies are imposed to buy a dedicated hardware “servers” for each service (This is because each service need a specific environment or specific packages).
Companies found their selves buying many servers but they do not avail from all of its resources (Memory, Storage …). Here come the new concept known as virtualization, where the VMware company introduced the first vitalized product in February 1999. So what is the virtualization ?
What is virtualization ?
Virtualization allows the creation of multiple simulated version of something (Operating system (OS), Server, Storage device, Network resources …) from a single physical hardware system.
The key component of virtualization technology is the use of software layer (above the hardware layer) known as hypervisor which the Host. Then, we have the virtual machines or Guests that are basically anything we want to virtualize.
Hypervisors take all the physical resources (Storage, Memory, Network resources …) and use them by the virtual environment. They can sit on top of an OS (like VMware or VirtualBox) or they can be directly installed onto the hardware (VMware ESXI or Proxmox VE).
Virtual machines works as a single file, they can be moved from one hypervisor or computer to another hypervisor (with the same type). Hypervisor relays virtual machines requests to the actual hardware, which means VMs do not interact directly with the hardware. Instead the hypervisor is the responsible for allocating the physical resources to the specifics VMs.
Moving beyond virtualization to the cloud
The starting question was : What if we put together several virtualized resources ?
The American company Amazon was the first to offering this type of service : In 2002, it invested in a huge computer park to avoid the overloads its servers as Christmas approaches, and find themselves with unused resources. She then decided to create a highly available platform and virtualized to rent these resources to companies, taking advantage of Internet to make equipment profitable. And that’s all started !!!
