Cloud characteristics

Today, many services that were referred to as hosted services a few years ago are now considered cloud services. While this is fine in many cases, some definitions help us understand cloud services and how they can be delivered. One of the most well-known specifications of these characteristics is the NIST definition of cloud computing (https://nvlpubs.nist.gov/nistpubs/legacy/sp/nistspecialpublication800-145.pdf), which helps us classify services but also characterizes cloud computing. Throughout this book, we will primarily refer to the definitions provided there.

In hosted services, we often had to write an email or call our service provider when we needed new services. The same applies to internal infrastructure. In the best case, the infrastructure was virtualized, and resources were available. In the worse case, infrastructure had to be ordered, and it took some time to order and install the hardware. These are things that are not imaginable nowadays...