Reliability in cloud computing
Let's first get an intuitive understanding of "reliability." A resource is said to have "reliability" if it often works when we try to use it. You will be hard-pressed to find an example of anything that is perfectly reliable. Even the most well-manufactured computer components have a degree of "unreliability". To continue with the car analogy, if you go to your garage and you can usually start your car and drive it away, then it is said to have high "reliability". Conversely, if you can't trust your car to start (maybe because it has an old battery), it is said to have low "reliability".
Reliability and availability are sometimes erroneously used interchangeably. As we saw with the car analogy, they are related but different and have different meanings. The terms have different objectives and can have different costs to maintain certain service levels.
Reliability...