Cloud computing is the basis of most of the services people use everyday. This technology is based on the interconnection of different web servers located in several data centers in various parts of the world, so that online applications can be executed on different machines: in this way, any service running on the cloud can benefit from fast loading times from every part of the world (as servers are located in different areas, each data center can meet the demand of the nearest users so that latency can be reduced), scalability and redundancy (if one server fails, others can provide the service and also data is safely propagated among the different machines so that there is a significantly low risk of losing it). Cloud computing is what makes the use of services like Google, Amazon, Spotify, TikTok, Instagram or Facebook possible in every part of the world, with always the same speed independently from how many people are currently using the service and with always the safety provided by redundancy.
The Different Uses of Cloud Computing
Cloud computing services may be used for several scopes. According to what written before, one of the most simple and popular use of these services is by running an online website or application meant to be always reliable and easily accessible. Still, cloud computing is employed in several cases: ultimately cloud services are also great in order to store sensitive data, in order to enhance technology for medical uses and even for robotics. As one can guess, companies providing cloud services carry a very high responsibility, as critical applications can totally rely only on these platforms. Here comes the need of being sure that the cloud provider on which a web application is hosted is reliable enough not to risk significant downtimes or - even worse - permanent data loss or leakages. That’s why one of the parameters one should take in consideration when choosing a cloud provider is the availability of a so called “Service Level Agreement“ (also known as SLA).
The Service Level Agreement: An Insurance For Your Digital World
The SLA is a specific contractual clause that most of the main cloud computing services include in the general conditions. The service level agreement consists in assuring a minimum level of availability of the cloud services that must be provided. For example, when referring to the availability of a virtual web server running on a cloud computing service, a possible SLA may impose a minimum availability of the services in the measure of 98% or 99% of a year: this means that, considering a whole year, only 1% or 2% downtime period is allowed. This is, of course, an example, as several kinds of SLAs may be provided. The main idea of a SLA is to:
- assure a minimum level of availability of the cloud service so that the customer is relatively safe to be online for most of the time: if we consider, for example, critical applications like e-commerce platforms, medical services and general solutions used by many people in different parts of the world, one can easily understand how important is to ensure the maximum availability;
- declare the penalties a cloud service has to pay to the customer in case it fails to meet the minimum service agreed in the SLA: the penalty may consist, for example, in a discount of the cloud service fee.
In addition, SLAs are not necessarily limited to the availability, but may also be set in order to ensure also a minimum level of performance, so that customers of a cloud computing service are also insured against eventual slow times or situations of failure to meet high demands.
SLAs represent a high responsibility to carry for the cloud services provider: this should not be surprising, as competition is high and also customers generally expect a great quality of the service they pay for. Providing a good SLA means generally showing a potential cloud user that the offered services are very reliable.
Not Only SLAs: What A Cloud User Should Also Ensure
SLAs are surely a great aspect to consider when choosing a cloud provider and the most common advice is to go with platforms that put it clear in their conditions what is the minimum level of service guaranteed and what are the penalties they are ready to afford in case of failure of meeting this level of availability. Still, service level agreements do not protect totally from critical issues that may affect the availability of a cloud platform: despite the high security measures carried by a cloud provider, absolute safety can’t be totally assured in general. Still, there are various good practices to always follow in addition to choosing robust cloud providers that offer good SLAs:
- hosting services in multiple data centers so that, in case of a single issue within a specific structure, there is the other one ready to carry all the demand. This is especially good if the service running on the cloud is meant to be accessible from different parts of the world, so that data centers in different locations may be chosen;
- scheduling regular backups of the virtual machines and the data hosted on the cloud service, so that an additional measure of safety is added against the risk of data losses;
- relying on more cloud computing providers, for example with the hosting of data on several services and with the use of load balancing technologies in order to redistribute workloads among the different cloud services: this is the so called multi-cloud approach.
Service level agreements and the best practices mentioned before are the keys to safely enjoy all the potential cloud computing has to offer.
© 2021 Alessio Ganci